Late Jeep 4.0L Engine Swap Into CJ

[jordan89oak]

So I picked up a 2004 XJ 4.0 engine and didn't realize the many differences in the block casting from the older 4.0. It wasn't until I started doing more research on the engine that I realized this, but I did get the engine for a really good price that was too good to pass up. 

Being that I've already put in some time into this engine, I HAVE to make it work. The first issue that I ran into was with the driver's side motor mount pads on the block. on the older 4.2 and 4.0 engine, the top bolt pad is pushed back about half an inch, and on the XJ 4.0 they are flush with each other. So, I went ahead and cut the top one off about 1/2" and that left enough thread for the bolt. There is some space between the mounting plate and the block, but not much, that I am going to use washers. I'm hoping that will work. For the passenger side, I had to do some cutting on the CJ7 motor mount brackets and a bit on the block due to block webbing interference. 

Now, the next issue that I am facing is with serpentine accessory drive. I wish that I could just use the 4.0 accessories, but being that I did not get the harness and computer with the replacement 4.0, I am going with the carb setup. So I will be using the 4.2 intake. Unfortunately, the water pumps are different. The older 4.0 engines have the built-in power steering bracket on the pump, so it's not like I could go this route to solve my power steering issues. 

This is starting to be somewhat of a headache because it is turning out to be a much more involved swap than I thought. I wish that I could just go the fuel injection route and be done with these issues. This would allow me to use all 4.0 accessories without an issue.

[Moses Ludel]

jordan89oak...An '04 4.0L would be from a TJ Wrangler or WJ Grand Cherokee, just a point of interest and clarification for parts sourcing.  If '04, you have the later cylinder head and the coil-on-plug (distributorless) ignition system and an oil pump drive with camshaft position sensor.  If the 4.0L engine has an ignition distributor and spark plug wires, it's 1999 or older.

I understand your commitment and the need to "make it work" at this point.  Your photos open in Google, so if you could copy-and-paste the actual photos into place here, they'd be visible, thanks!  I would like to see what you're up against, so I can make some suggestions to help facilitate your fabrication work and get you through this project.

On the carb set-up, you will be modifying to get an intake manifold port match and bolt alignment, as the 4.2L and 4.0L cylinder heads and ports differ slightly.  This can be done, just be sure the ports and the gasket/seal match up.  You may need an aftermarket, non-OEM manifold gasket set.  In any case, make sure the intake and exhaust manifolds fit properly, port match and seal properly.  (There may be a massaging of the early carburetor intake manifold stud/bolt alignment to fit the 4.0L head.)  I would use the later "header style" OE exhaust manifold if it came with the 4.0L engine and will fit/match up with the carburetor (4.2L) intake manifold.  The 4.2L cast iron manifold does not flow as well.

I'm guessing you're not concerned about emissions?  Or are you using all of the 4.2L carburetor and emissions components to run the engine as a 4.2L stock complying setup?  As you note, EFI would be a real asset.  The concern with a late coil-on-plug era MPI/EFI system and PCM is added interfaces like security that complicate the wiring and chassis electrical hookup.  1991-98 (1999 non-coil-on-plug as well) 4.0L engines and PCMs are much better candidates for retrofit swaps and harness splicing.  The HESCO/Mopar EFI Conversion wiring harness was a way to bridge the wiring gap.  Not sure whether HESCO sells the single rail EFI (1997-99) prototype wiring harness as a separate product.  That worked for 1991-98/99 non-coil-on-plug EFI 4.0L engine conversions.

On one 4.0L swap into an early chassis, I used the early V-belt drive system.  (In that regard, perhaps the earlier 4.2L serpentine belt and bracket system could be swapped over to the 4.0L engine?)  Make sure that the water pump has the correct rotation/direction for the type of accessory drive system you use.  There is a reverse and straight rotation pump, you likely know this already.

Glad to compare notes and add comments if helpful...

Moses

 

 

[jordan89oak]

Hi Moses,

Thank you for all of the wonderful information. My apologies for the pictures, I thought that they would show up directly on my post since they were showing up when I pasted the link. 

I have been doing a ton of research on this engine (should've done way before), and have come across the need to cut the 4.2 intake dowel location, but that is not that bad. As for porting, I have the carbide bur for that. I will be using the 4.0 intake gasket, and still need to get the 4.0 header style exhaust manifold, as the Grand Cherokee engine came with a two piece exhaust manifold.

My biggest issue at the moment is the water pump that is preventing me from using the CJ7 accessory drive system (Serpentine reverse drive). the older 4.0 and 4.2 engine water pump has the ear to attach the power steering bracket to it. This 4.0 does not have it, and the bolt pattern is the same, except in the lower right side bolt location. I was thinking about drilling and tapping for that bolt. I hope there is enough block material there for the job.

As for emissions, I am not too concerned about the visual inspection. The Jeep will have a complete new exhaust and catalytic converter to keep things clean, as well as a fully functional EGR system. I am doing away with the coil setup and picked up a CRT HEI distributor for the engine. 

I will figure out how to post pictures directly and post them in a bit. 

Thanks Moses!

[Moses Ludel]

Jordan89oak...You're welcome...The 4.2L intake dowel does come up and is a simpler fix.  When Mopar used the '95 YJ Wrangler 4.0L as a prototype for the 4.2L EFI conversion, an off-the-shelf 4.0L intake manifold was part of the conversion kit.  This works both ways with the slight modification.  Make sure ports align and don't get carried away with the port matching.  Make sure the intake gasket will seal at both sides.

Talking about the MPI/EFI conversion kit, I have been suggesting the use of that kit's engine wiring harness for making an EFI conversion with 4.0L recycled engine swaps.  There is a part number for this wiring harness.  You would need a 1991-95 60-way (pin) PCM to complete the conversion.  This setup uses an inline, properly rated fuel pump, as the CJ has no provision for an in-tank pump.  (An '87-'90 YJ Wrangler does allow for an in-tank pump.)  Apparently, this harness works with either a single rail (1997-99 spark wire ignition) or two-rail (1991-95 4.0L with a tank return line) MPI system.  The single rail systems require a pressure regulator that mounts near the fuel tank, another part still listed through Mopar Performance or HESCO.  (Jeg's and others list it, too.)  That regulator patterns off the 1997-up pressure regulator that mounts atop the fuel pump module.  In this application, the modified regulator fits inline near the tank. 

If anyone is considering a pre-coil-on-plug 4.0L swap into a CJ or '87-'90 YJ Wrangler, and they want to keep EFI with a spark wire ignition, this Mopar harness could be the alternative to using a donor vehicle harness.  The kicker is the price:  $605 retail at Jeg's and other sources.  (For that amount, I would get a donor harness and 60-way PCM from a 4.0L 1991-95 YJ or XJ model at a recycling yard and pore over the wiring schematic to mate it up.)  At present the Mopar EFI Conversion Kit is "out of stock" and likely out of production. 

Retail price for the 4.2L Jeep/Mopar EFI Conversion, which I have promoted strongly since day one, has inched from $1400 to $3,300 from the mid-nineties to present.  $2,695 is often the price point...For this amount of money, I would perform an emissions legal, recycled GM 350 TBI or an LS 5.3L/5.7L iron block V-8 conversion.  From what you're encountering, Jordan, the V-8 swap might actually be easier in some ways.  V-8 conversion "kits" are available from a variety of sources, and Painless has a drop-in wiring harness for the Chevrolet V-8s.

Though not as precise as MPI with integral fuel-and-spark management (certainly not a deal breaker for a stock 4.2L inline six), Howell EFI/TBI is available for far less and is emission legal with a California E.O. number.  Howell uses off-the-shelf, readily available GM components for its TBI system.  Howell provides a reliable system that is easier to install and far more affordable.  While the Mopar system will make more horsepower, for a trail running 4x4, do we really care?

Here is the current, live Mopar part number for a 4.0L conversion wiring harness:

Mopar Performance Wiring Harness 1981-90 4.2L Jeep...Part Number:  P5007148AB

Additional part numbers straight from the Mopar Performance Catalog:

"MPI Conversion Kits and Service Parts Designed to make your 1981-90 Jeep® vehicle more efficient and powerful. The kit replaces the stock carburetor, intake manifold and other major components with multi-point injection (MPI). Each cylinder has its own injector that is activated sequentially according to the firing order to precisely control individual fuel requirements. These MPI Conversion Kits are self-compensating and run equally well from sea level to terrain above 12,000 feet. Mechanical components are based on production 1995 Jeep vehicle parts:

P5249686AE EFI Conversion Kit, Automatic Transmission, Emissions Exempt D-265-21** for 1981-90 4.2L Jeep Engines

P5249610AE EFI Conversion Kit, Manual Transmission, Emissions Exempt D-265-21** 1981–90 4.2L Jeep Engines

P5007146 Engine Controller, Automatic Transmission, 1981–90 4.2L Jeep Engines

P5007147 Engine Controller, Manual Transmission, 1981–90 4.2L Jeep Engines

P5007150 Fuel Pump, Auto/Manual Transmission, 1981–90 4.2L Jeep Engines

P5007148AB Wiring Harness, 1981–90 4.2L Jeep Engines [patterned for a 1991-99 4.0L spark wire ignition distributor application]

P5007046 Crank Sensor Bracket, 4.2L Jeep Engines"

For those curious how Mopar EFI Conversion hardware fits, possibly useful for 4.0L MPI/EFI engine swaps, here are the instructions for the MPI kit installation:

Mopar 4.2L Jeep EFI Conversion Installation Instructions.pdf 

The extra bolt on the late 4.0L water pump is interesting and disappointing.  We were once concerned solely with the pump's direction of rotation, whether the engine had a V-belt or serpentine belt drive system and the pump's pulley flange/shaft stick-out length.  Let us know your workaround for this one.

Moses

[jordan89oak]

Hi Moses, 

I am back with another update, and hopefully pictures that work. I pasted them onto the thread. So I went out and messed with the engine and mocked up some of the accessories to the engine. The first picture shows the missing water pump bolt on the lower right hand side. The second picture shoes the missing bolt hole for the rear power steering pump bracket mount. Both, the water pump and the power steering pump, are for a CJ7. 

My plan was to just go ahead and drill and tap the missing bolt holes for the water pump and the power steering pump. But when I moved on to the alternator side, I ran into a bigger issue that practically renders the idea useless.

The remaining two pictures show a Grand Cherokee alternator bracket mounted because the CJ7 just didn't work. The CJ7 alternator bracket has a long bolt location going down towards a bolt hole on the bottom. The issue with this block, as seen on the last picture is that, not only is the bolt hole not there (least of my issues), but the webbing and those raised portions of the block interfere with the CJ7 bracket's lower portion. The actual lower bottom bolt locations for the original Grand Cherokee mount is raised and interfere. 

Looking at the offset difference between the Grand Cherokee pulleys and the CJ7 pulleys, I can't see a way to make this work. I did find that some time ago someone was making a carb adapter plate for these 4.0 engines, which would have been perfect, but he is no longer making them. This would have allowed me to use the 4.0 intake and keep a carb setup, and would have definitely been cheaper than a full efi conversion.

Those EFI systems are so pricey. I actually have an LS engine sitting on an engine stand that would be so much easier to swap into the Jeep, but I don't have a tranny to work with the engine. Looks like a standard rebuild of the 4.2 would be the best thing to do. I have another 4.0 head that I can put on that engine, along with a mild cam for it to wake it up a bit.

Conclusion: Unless you are doing a full EFI conversion, that will allow you to use the stock 4.0 intake, you will not be able to make a 2004 4.0 engine work.

[Moses Ludel]

jordan89oak...I'd do the LS V-8 swap at this point, easier than the alternatives.  Advance Adapters is my source for adapters.  Which transmission do you currently have?  What year is the CJ chassis?  Glad to offer some ideas and pointers.

As for photos, still no images.  Here's the easiest way to post photos: 

1) With your photo files in a folder on your PC or laptop, click on the "choose files" to the right of the paper clip (bottom of Reply window).  This should open your file explorer.

2) Highlight the photo files (.jpg, .png, .bmp, etc.) and click upload or open.

3) The files will upload and line up below the Reply window.

4) Put your cursor where you want the photo to rest in the Reply.

5) Click on the image file below the Reply window.  The image should pop into place.

Try to upload photos again.  Let me know if there is difficulty or a glitch at our end...Thanks!

Moses

[jordan89oak]

I hope the pictures worked this time? I would have done the LS swap, but my Jeep came with a T5 transmission, which would get destroyed behind and LS engine. It's an '82 CJ7. I have explored so many options to get this 4.0 in, but I just don't see a way without going the fuel injection route. 

[Moses Ludel]

The photos are perfect, thanks!  I see the trouble.  Makes one wonder what possessed Jeep® to alter these castings with so few years of production left and so many common years behind?  Mounts and brackets needed slight massaging with some 4.2L/4.0L swapping, but nothing this dramatic.  I would fabricate or modify the brackets to match with existing threaded block holes.  As you already have decided, I would not drill and tap the block.  What is the block casting number?

There's one approach regarding carburetion for a 4.0L.  Clifford Performance offers a Ram Flow inline six carburetor intake manifold for the 1991-2006 Jeep 4.0L.  The usual routine is either a 4-barrel or the mount can be reduced to a two-barrel with an adapter.  Clifford also has a performance header for the 4.0L to match up.  Here is the link for info:

https://cliffordperformance.net/6-8-catalog

Give Clifford Performance a call and see whether they currently offer the components shown at the site.  What ignition distributor do you plan to run?

Moses

[jordan89oak]

Quote

 

I was looking at Clifford intakes intakes, and explored that option as well. I truly don't understand what would possess them to do something like this.

The biggest issue would be getting the power steering pump. If I could somehow get that to work, my troubles would be over. The problem with the CJ7 PS bracket is that it is mounted using the ear on the water pump, which the 4.0 Grand Cherokee pump does not have. I'll keep digging and try to find a solution to this issue. 

As for my ignition system, I went with a CRT HEI distributor. 

[Moses Ludel]

jordan89oak...So a CJ water pump will not fit the late 4.0L block?  Mounting holes for the water pump do not align?  Can you fabricate mounting plates for the CJ power steering pump that would align with the late water pump mounting bolt pattern, using the water pump bolt holes to secure the fabricated P/S pump support bracket?  Or would this make pulley alignment difficult? 

Can you use the late style power steering pump and brackets?  If that works, you need to compare and match the pressure output from the late pump to a CJ pump and steering gear.

What would it take to make this swap work?  For fab'ing brackets, do you have a welder and basic fabrication tools?  Once past the power steering pump, you have the alternator...It would be difficult adapting a late 4.0L alternator to the CJ, as the alternator uses the PCM to regulate voltage.  What about brackets for mounting the CJ alternator?

The HEI distributor is a standalone, which does work with a carburetor.  You have two distinct paths here.  The Clifford manifold and an aftermarket carburetor will not pass a smog visual check.  Nor would a Holley or other aftermarket carburetors meet tailpipe emissions.  This is a dilemma.

Moses

[jordan89oak]

Well, I am back for an update. I decided to tear into the original 4.2 engine yesterday, and things just keep getting worse. I was going to do a rebuild of this engine and put it back into the Jeep for now, but someone really did serious damage to the 4.2. 

While tearing the engine apart, I found a a spun bearing on rod number 7. Surprisingly enough, the crank does not have any scoring or anything. It actually feels smooth. I'll have to check it with a micrometer. A few of the pistons came out with broken rings, but that was not the worst of it. As you can see, one (at least I hope only one) of the pistons is cracked. I hadn't noticed it until I was picking things up and about to call it a day. Right out of the corner of my eyes, I noticed the crack and it just ruined my entire plan of a simple rebuild. I just want to enjoy the Jeep, but things keep getting worse. 

I'm probably going to have to look for a harness and computer for the 4.0. If I can source that at a good price, I'll be able to use all of the front accessories and just drop the engine in. I've seen some computers on eBay that come with the key and immobilizer. 

I'll keep this post updated as I go.

 

[Moses Ludel]

Oh, boy, Jordan89oak...this really is disappointing.  Aside from the testimonial to the abuse these engines can take, there's only a rebuildable core here.  My guess is that the very loose timing chain jumped teeth?  Look closely at the valves and piston crowns for signs of valve interference with the pistons and bent valves.  (The chain looks loose enough for valve interference whether it jumped a tooth/teeth or not.)  It's academic now, although you do want to check the rods for straightness if you decide to use this crankshaft and rods for a 4.6L stroker build or 4.2L restoration.  

Do keep us posted.  The late 4.0L obstacles need clarification.  We're always generalizing about 1991-up 4.0L engine swaps and putting these engines in a single category.  There's an obvious distinction (cylinder heads, fuel injection type, etc.) between 1987-90 4.0L XJ engines and the later 4.0Ls.  The differences on the late C.O.P. engines also have to be considered.  You've proven that for us.

It's clear you're looking for a cost-effective way out of this.  Do you have the 4.0L flywheel and crankshaft position sensor (CPS)?  You need a TDC reference/trigger signal as you go forward with MPI/EFI.  The CPS mounts to the 4.0L bellhousing and requires the EFI flywheel for a CPS signal.  If you're using the original CJ-7 transmission, there's an issue here.  The later (EFI/MPI) bellhousings will not mate to the earlier CJ-7 transmissions.  We can discuss this.

Moses

[jordan89oak]

Hey Moses,

It was definitely a disappointing engine tear down. I was inspecting the positions closer today and discovered another piston with cracks in the ring land. I’m attaching a picture of that, and another showing the mangled rod bearing.

I’m really surprised that the engine wasn’t knocking like crazy when I fired the engine up when I first bought the Jeep. 

I might have a solution to the 4.0. I have a friend that may be able to make me a carb adapter for the 4.0 intake. If he’s able to do that, that would solve my problems.

As for the flywheel and CPS, I don’t have them. I’ve seen some folks drill a hole into their existing bellhousing for the CPS as a cheap alternative. I’ll keep you posted on what happens. I’m going to go ahead and draft a template for the adapter. 
 

 

[Moses Ludel]

Wow, the rod bearing is really damaged!  Yes, amazing it did not knock.  The loose timing chain and retarded valve timing dramatically impaired/dropped manifold vacuum.  Maybe combustion was so incomplete, and compression so low, that the engine did not produce a knock.

The carb adapter is a workaround, you have the standalone aftermarket distributor/oil drive already.  The coil is built into the HEI cap.  Does the vehicle require emissions inspection?  Or is it age-wise outside the window? 

The template sounds interesting, you need to take the crankshaft pilot bearing and transmission input shaft stick-out length into account.  Can you simply use the 4.2L bellhousing and OEM spacer "shim" with your existing transmission and the 4.0L block?  Without the need for CPS, you can work around the bellhousing/adapter issue.  Important in any case is the stack height from the crank pilot bearing and crankshaft flange, to the flywheel face, clutch disc splines and the face of the transmission.  Make certain everything aligns correctly.

Moses 

[jordan89oak]

Hey Moses,

I had actually already ordered a pilot bearing from Novak. I searched around for pilot bearings at the local auto parts store, and came across one on the web that could have possibly worked. I ended up going with Novak to avoid extra hassle. As for smog, it will need to go through a sniffer test, but I have all new exhaust, including a CARB legal cat. 

This morning, I came across a local ad for an AX15 transmission at a solid deal that was too good to pass up. I drove over to San Jose, California and picked up an AX15, which was also attached to the stock 4.0 off of a '93 Wrangler. I took them apart and discovered a pretty much new clutch. The guy I bought it from has a bunch of Jeeps and only needed the body. I'm still going to do a leak down test and thorough inspection to make sure things checkout.

I've read about folks mating the AX15 to LM7 engines, which I happen to have in my garage. I would rather drop this 4.0 because I just want to get this Jeep running.

I know it's not Jeep related, but here is a pic of my Nova. I dropped an LQ4 with some goodies and a built T56 into it. 

[Moses Ludel]

jordan89oak...This is shaping up...to a degree.  You now have a very late COP 4.0L, a true '93 4.0L with an AX15 transmission and your original 258 engine.  The AX15, however, does need an adapter to the Dana 300.  It's not a difficult adaptation, as the transmission and T/C are each 23-spline.  You want to keep the Dana 300 in its passenger side drop orientation.  Here's the scoop:

https://www.advanceadapters.com/products/50-8603--jeep-ax15-adapter-kit-to-dana-300/

So the '93 engine also came without its original EFI/MPI, wiring or PCM?  Still thinking about the carburetor adapted to the MPI intake?

I like the LQ4...nice.

Moses

[jordan89oak]

Unfortunately, still didn't come with the harness or PCM. The guy used it on his other project. I wasn't even expecting for the engine to be included in the deal, but when I got there, he said to take everything. The transmission does have the CPS attached to it. I was looking at the adapter for the AX15 to the D300. This definitely opens up some possibilities. 

I was looking at harnesses and PCMs for this engine, and to my surprise, they are pretty pricey online. Moses, could I use a Cherokee harness and computer with this engine? They have a bunch of Chrokees down at my local Pick&Pull.

[Moses Ludel]

Yes, XJ Cherokee is the same.  The 60-way computer is the goal, pre-OBD-II.  a 1991-95 would be a facsimile of the Mopar EFI Conversion kit.  Any 1991-95 YJ or XJ model would work, these are pre-OBD-II.  Mopar advertised the conversion kit as "1995 YJ Wrangler 4.0L" for emissions certification.  The system was released during that era.

Look for a 1991-95 XJ Cherokee.  Avoid 1996-up.  Mopar even sells the wiring harness separate from the kit, though it's very expensive.  I posted that information and part numbers (above) on February 3rd.  Or you can use a 1991-95 OEM XJ or YJ harness and strip out the necessary wires, splicing accordingly as others have done.  It's not daunting but does require an FSM with the wiring schematic. 

Mopar FSMs are now available as CDs on eBay or as used manuals.  Get a period FSM for 1991-95 XJ/YJ.  I have the 1994 Mopar FSM on my shelf, it covers both of these models.  I refer to it all the time.  You will, too, once you land on the system you want to run.  The AX15 is also covered in that manual.  For clarification, your "newest" engine and AX15 are definitely 1991-93 era.  The block is likely the original 1993, casting number fits 1991-95.  The clutch release bearing is still hydraulic type.  1994-up is an external slave and mechanical throw-out bearing with a release arm.  Seller on the up and up!

Moses

[jordan89oak]

Well, I am back with an update. Unfortunately, luck is not on my side when it comes to Jeeps. I took the head off of the 4.0 that came with the AX-15, and things immediately took a turn for the worst. 

This engine had damage to the front of it. The fan and clutch were damaged, and the water pump shaft was loose. After removing the head, I noticed a hole in that cylinder right behind the water pump. 

I really thought that I could give this engine a quick refresh and drop it into the Jeep to enjoy it. I've thought about getting it sleeved, but I am not even sure if that would be possible. 

I've drawn up a template for a carb adapter for the Grand Cherokee 4.0 engine so that I can use the FI intake and power steering pump. 

I will continue to post updates on this engine situation as I go.

 

 

[Moses Ludel]

Wow, Jordan89oak, really sorry to see this damage.  Unexpected for sure, the cause is unusual but clear!  Would your complete LS V-8 be a more practical engine option at this point?  If the LS is complete, you could have an emission legal engine in the end. 

The emission compliance process would involve a referee station in California if a visual inspection is part of the process on a vehicle of this vintage.  At least for later chassis swaps with the LS V-8, California wants the donor engine to include the exhaust system and cat(s) from the donor vehicle.  If you consider the LS V-8 swap, do your homework on the referee station requirements and the referee station's expectations before tackling the project.  They're happy to see a later, cleaner burning engine, but the swap must follow the CA guidelines for an engine change in order to pass the visual inspection.

Watch this video I filmed at Advance Adapters.  Steve Roberts walks through a California (50-State) legal emissions swap of an LS V-8 into a TJ Wrangler.  There are several points made about the equipment required by the referee station.  Determine how much of this applies to your '82 CJ-7 Jeep and an LS V-8 swap:

https://www.4wdmechanix.com/HD-Video-Advance-Adapters-Jeep-TJ-Wrangler-LS-V-8-Conversion?r=1

Moses

[jordan89oak]

Hey Moses,

This was definitely a disappointing discovery, but I guess I can't be too mad about it since I initially thought I was only getting the transmission for the price that I paid for it ($250). I had already made plans to turn this into a budget 4.5L stroker, and was just about to go and get the 4.2 crank and rods machined and checked. 

The LS that I have sitting on the stand is a complete engine with computer and harness. I even have the DBW peddle that goes with it. I thought it would be easier to drop in a 4.0, but it looks like an LSX swap might be the best thing to do. It seems like it would be easier to deal with the wiring of an LS engine, as opposed to that of a Jeep.

I took a look at the Advanced Adapters website. The mounts are affordable. The only thing that would get expensive would be the catalytic converters for an emission legal swap, but doable. The video was helpful in understanding the complexity of a legal emission swap. I remember one requirement being that the vehicle that the engine came out of has to be under the same classification as that of the swap vehicle. The 6.0 that I have came out of a truck, but I also have a 5.3 that came out of a Tahoe.

I have to crunch some numbers and do more research on the emission legal swap. 

[Moses Ludel]

jordan89oak...Yes, you're correct about the vehicle category for the donor engine.  If the 6.0L donor was a "Class 1" (old tier system) or 1/2-ton truck emissions, that would likely be okay.  If that engine is from a truck with a higher GVWR (3/4-ton let's say), that won't work.  Your CJ is in the same emissions class as a 1/2-ton (1500) truck or a light SUV like the Tahoe, or a passenger car application.  You can confirm the emissions tier by engine code and compare with the CA emissions program.  BAR now has a good deal of information online about engine changes like this.  The 5.3L from a Tahoe should not be a problem at all.  Is that an iron block?

Though a V-8 swap is not "simple", you're not having an easier time with the Jeep inline sixes.  The end game would be so much better with the LS 5.3L or 6.0L (if legal).  Modern, fuel efficient, you're familiar with the engine platform and the LS systems.  Just makes better sense.  Once done properly, you would be much happier with the outcome.

Do you have the fabricating equipment/welder for the motor mounts and such?

Moses

Moses

 

[jordan89oak]

I guess I find the LSX swap easier because I am familiar with it. There is just SO MUCH cross configuration within the LS platform. I was a little disappointed with the redesign of the 4.0 in the Grand Cherokee engines. There also seems to be more support for GM ecm programing than for Jeep ecms.

I do have the needed fabricating equipment (MIG and TIG), as well as HP tuners for computer programing. 

[Moses Ludel]

Sounds like time for the LSX swap!  Do some homework on CA emissions expectations.  Pleased to know you're equipped for the project, including the tuning.  Go for it!

Keep us posted, photos would be helpful to others.  This is a time-honored vehicle for a V-8 swap, the 5.3L would be plenty if that's the engine you choose.  Advance Adapters will be a great resource for the mate-up pieces.  That's the core of their business, the tech line will be helpful at 1-800-350-2223.

Moses

[jordan89oak]

Hey Moses, 

I am back with an update. So, I was online searching for LS swap components when I came across an the 4.0 efi to carb adapter that I had been looking for all of this time! I know an LSX swap would have been great, but this will save me a lot of time and money. 

The adapter is very well machined. I am going to have to use the original spacer that came with the carburetor, as the throttle linkage hits the adapter plate. This will now allow me to run all of the Grand Cherokee accessory components.

I have to test fit the engine to make sure that it will drop in, being that I had to cut into the driver side mounting tab on the block. If this all goes well, I will start gathering the pieces, slowly, for an LSX swap later down the road.

I will keep you posted with updates.

Jordan

[Moses Ludel]

jordan89oak...Interesting development...So back to the 2004 4.0L?  I'd like to see your workaround for the engine block and accessories mounting when you get this all together. 

Without opening a hornet's nest again, what will you do for your emissions inspection with what looks like a Weber carburetor on a 4.0L engine casting?  Can you make this pass?  I don't believe the Weber ever earned a California E.O. Number.  The 4.0L block casting is a late EFI/MPI engine.  If you make the long block look like a 4.2L installation for a non-referee "normal" emission inspection, you would need  the Carter BBD 2-barrel carburetor and all OEM emission equipment in place to pass the visual portion of the inspection in an '82 CJ-7 4.2L chassis.  The 4.0L EFI intake manifold has no provision for the 4.2L OEM EGR system.

Can you fit the 4.2L exhaust manifold to the 4.0L head, using the 4.0L intake manifold as well?  Can you modify the EFI intake manifold to work with the '82 4.2L exhaust manifold and EGR valve/system?  Does the engine bay still have all the 4.2L emissions equipment, OEM ignition and CEC, wiring, etc.?  Do you have the BBD carburetor, air cleaner, etc.?  Will the carburetor adapter accept the Carter BBD carburetor?

This is essentially what the OEM 1982 CJ 4.2L intake and exhaust manifold layout looks like with provision for the EGR components:

Moses

[jordan89oak]

Hey Moses,

Yes, I am going to give the '04 4.0l engine a go. Unfortunately, the Weber carb does not have a CARB number that will pass inspection. As long as my emissions are good, the visual should not be an issue.  I will do everything that I can to make it all look "original," with the exception of an EGR system. 

The reason I was initially not able to use this newer engine was because the use of the 4.2 intake would not have allowed me to mount the power steering pump, as the threaded pads are missing, and the '04 water pump does not have the mounting tabs for the power steering system. The exhaust manifold will not work on the 4.0 heads, so I have a 4.0 exhaust manifold for that. Also, the stock 4.2 exhaust manifold is cracked pretty bad.

I haven't looked into modifying the 4.0 intake for EGR adaptation, but I will definitely look into that. I stripped the original computer and wiring. I have all of the stock components in a box in my garage. I will be adding a new catalytic converter and tuning the carb and timing to help with passing the sniffer test. As long as I can pass the sniffer, I am good to go.

The other issue that I am faced with is the alternator, being that the computer is used to excite and charge. What I have read as a solution is the use of an old Mopar external regulator. I am planning on using a 2004 4.7 Durango alternator (160Amps), as I have read that they will work on these engines.

 

[Moses Ludel]

Let us know how the alternator issue resolves...Moving forward!

[jordan89oak]

Hey Moses,

I'm back for a quick update on the project. So, I mocked things up yesterday. I am using the earlier 4.0 header with the '04 intake. It was not exactly a direct fit, so I had to massage the  #6 primary. I'm also having to run a spacer in between the car and the actual adapter. Even with the spacer in place, the throttle linkage is binding on a raised casting number. That's not an issue, I will grind that off and everything should clear.

I haven't found plugs for the injectors, being that I will not be using them. The quickest solution that I see for this is just keep them, and the fuel rail, in place.

There is a paper thin spacing between the intake runner and the exhaust primary, but everything appears to seal tight. The pictures show the manifolds mounted without a gasket, and things are flat against the head.

My plan is to mock the engine and tranny into the Jeep this weekend, as I am a bit worried about the block modifications that I had to do on the driver side mounting location on the block. Hopefully, things will drop into place. If they do, I put in the new pilot bearing, clutch, and finally mate things and drop them into the Jeep.

I will keep you posted once I have done this.

[jordan89oak]

Picture of the massaged header. I was going to go with the stock exhaust manifold with the flex pipes at the 1 and 6 primaries, but it's a good thing I didn't. They would not have fit, as that is the area where I had to make a dent on the header. I went with an ATP header, which I got at an amazing deal ($19), so I picked two up. I am going to run a flex pipe right beneath the collector in an attempt to avoid cracks. 

[Moses Ludel]

I'm curious how this turns out...The ATP header price is amazing, you have an extra one for use or bartering!  What is the concern on the motor mount?  Need to share a picture?

[jordan89oak]

I had to cut the top motor mount nub (as seen in the picture), and there’s a some space between the block and the mount for the bottom bolt holes. It’s not much, and I’m hoping that things will line up and I can just put a thick washer in between. 

[Moses Ludel]

Does this bracket line up fore-and-aft with the 4.2L frame mounts?  You're using a three-bolt method of securing this bracket to the engine as shown in the diagram below?  Are all three of these block holes used?

Rather than use spacer washers, would it be better to weld a piece of flat strap metal across the backside of your engine bracket and have the strap act as a spacer?  That could provide additional strength for the bracket.  You would drill bolt holes through the strap at the lower bracket holes.  The strap would be the thickness you need to fill the space.  Otherwise, your thick washer approach would work.  Use Grade 8 washers, thick enough to fill the space with one washer in each bolt position.

[jordan89oak]

The three bolt holes will be used. That’s a good idea. I’ll have to look to see if I can make that work. 

[jordan89oak]

Well, late night update. I just got done messing around with this engine. I did a test fit first and found that the engine dropped right in. As previously mentioned, I was worried about the motor mount modification that I did to the block not working, but everything worked out. 
 

After mock-up, I went ahead and mounted the new flywheel and clutch, mated the engine and transmission together, and drop them into the Jeep. I’m so happy that the engine drop into its new home!

Now that those things are in I have to pick up the new alternator and start putting the accessories together. I have the new voltage regulator and pigtail. I also have to clean the firewall up a bit by the battery tray, I picked up a dual battery tray for the Jeep, so I’ll be doing that wiring as well. 
 

So, for those fitting a 2001-2004 XJ 4.0 engine into their CJ7, or Wrangler, be prepared to cut the top motor mount nub, as well as a small portion of the passenger side casting webbing next to the motor mount. 

[jordan89oak]

By the way, if you plan on using ARP head bolts like I did, the metal valve cover will not work. You may be able to grind a bit off of the valve cover to clear, but the plastic valve cover from the older 4.0 will work. 

[Moses Ludel]

jordan89oak...Groundbreaking results.  Very helpful to others who find themselves staring at a late 4.0L block for their CJ.  You must be relieved!

EFI would be an alternative if the installer has a complete engine, PCM, wiring harness and the ability to sort out the late engine wiring and its interface with the vintage chassis.  This would include the alternator as you discussed.

The Mopar and HESCO EFI conversion kits use the 1991-95 era 60-way PCM.  The late MPI/EFI with an OBD-II PCM setup would require sorting out all the wiring and making it work.  Has anyone done this?  It would be helpful to know your experience...

Moses

[jordan89oak]

I'm not sure if anyone has successfully adapted an earlier HESCO EFI conversion kit on a newer engine like this. I read about folks adding the newer style intake manifolds on their older 4.0 engines and making it work with their existing engine management systems, so it might work. Most of the electronic components and sensors are on the intake itself.

I still haven't picked up the alternator for the Jeep, but I am going to try to get the other things mounted up while I get that. I will be using the CJ7 oil pan, so I have to swap the pickup tube and oil pan as well. I know, I should have done that while on the engine stand, but I wanted to get the engine and transmission into the Jeep already. I made this same mistake with my '74 Corvette. I'll also be doing a new exhaust (new catalytic converter as well) system.

Hopefully, I can get this Jeep running so I can finally move on to the suspension that includes a 4" lift, heavy duty ball joints, etc.

[Moses Ludel]

Fortunately, the oil pan can be a cake walk if you use a FelPro pan gasket.  It even comes with plastic retainer pins (Snap Ups) to hold the pan in place while you start bolts.  You'll be lovin' life.  I did FelPro when I changed the rear main seal in our '99 XJ 4.0L.  All that for $20 at Summit!

https://www.summitracing.com/parts/fel-os34308r/make/jeep

Q: Will this gasket come with the oil pan/gasket alignment tools or are they purchased separately? seems I read it came with but did not see any mention of it...if not, will the Dorman tools work?

A:  The OS34308R does come with 5/16" ES72863 Snap Ups.

[jordan89oak]

6 hours ago, Moses Ludel said:

Fortunately, the oil pan can be a cake walk if you use a FelPro pan gasket.  It even comes with plastic retainer pins (Snap Ups) to hold the pan in place while you start bolts.  You'll be lovin' life.  I did FelPro when I changed the rear main seal in our '99 XJ 4.0L.  All that for $20 at Summit!

https://www.summitracing.com/parts/fel-os34308r/make/jeep

Q: Will this gasket come with the oil pan/gasket alignment tools or are they purchased separately? seems I read it came with but did not see any mention of it...if not, will the Dorman tools work?

A:  The OS34308R does come with 5/16" ES72863 Snap Ups.

I’ll definitely be going with the FelPro gasket. I’ll keep things updated here for future reference. 
 

Thanks Moses!

[jordan89oak]

Quick update, I just got the alternator and the Durango 160amp alternator drops right into place (4.0 Grand Cherokee bracket). I’m hoping to install the new timing cover gasket, oil pan gasket, water pump, etc. this weekend. I’ll hopefully get the wiring done as well.

I’ve already mounted the new HEI distributor into place. For the oil pan, I was planning on using the 4.2 pan, but I’m going to stick with the 4.0 pan instead. 
 

I’m trying to figure out the wiring for the alternator. These newer alternators use a 4 gauge cable directly to the battery, I believe. The original  CJ7 uses a wimpy 10 gauge wire. I’ll have to look at the wiring diagram to see if this is where the cj7 fuse panel gets its power from. If not, I’m thinking about running a 4 gauge cable from the lug of the alternator to the battery. 

[Moses Ludel]

You could run a frequency welder with this late alternator!  Wire carefully, that's a lot of amperage floating around...Cool!

[jordan89oak]

Hey Moses, 

I'm back with an update. I was hoping to have the Jeep up and running this passed weekend, but I wasn't able to make it happen. I did work on the Jeep, but I did not get to the wiring part of things. I did some research on the wiring, and have prepped the wiring for the fuel pump and the external voltage regulator. I picked up information from Hot Rod Magazine to wire the fuel pump off of an oil pressure switch (Part# PS64), which is pictured bellow. As for the voltage regulator, alternatorman has good videos on YouTube on how to wire this system up. The attached picture (from the backyardmechanic website) is pretty much the same as wiring instructions from the video.

As you can see in the engine picture, I still haven't installed the crank pulley due to me not having an install tool, so I'll have to go and rent one this week. The carb is not mounted yet, but that is not a big issue. Another thing I will have to worry about is the throttle linkage. I'll work that out as I go. 

The pigtails for the fuel pump relay and voltage regulator have all been marked to make installation easier. I still have to figure out where I will get my hot in crank and hot in start power for the oil pressure switch/fuel pump wiring. I need to look for a  good wiring schematic to figure this out. 

I have a few days off of school this week, so hopefully I can really get the Jeep running by this weekend. I'll keep things updated here for future reference. Hopefully it will be of help to someone later on down the road.

 

[Moses Ludel]

Interesting...Historically, we picked up auxiliary voltage during the cranking mode from the starter solenoid switch.  The switch closes to power the starter, and the small terminal pole powers up with a full 12-volts (usually for the ignition circuit, which is incidental).  When the cranking mode ends, the solenoid opens and that small amp circuit loses 12-volts as you would want. 

If that is a useful source, wire from the terminal to fuel pump with adequate gauge wiring for the pump.  You want to fuse that lead.  If desired, an in-circuit 5-pole common Bosch type relay would work, too.  The lead from the starter solenoid would close the relay during cranking mode.  Fuse that circuit.

Once the engine fires and the ignition switch is released to the ON position, you can tap 12-volts from an ignition ON source with enough amperage capacity to run the fuel pump—or you can use that 12-volt ON lead to close a 5-pin relay and run heavier amperage pump power from the relay to the pump.  Make sure it's enough wire gauge amp capacity to power up the fuel pump.

I like the oil pressure function if that's the intent.  Nice engine protection in the event of oil pressure loss...I'm guessing that this oil pressure sender has a low enough set point to close the switch while the engine is in cranking mode?  It takes a bit of cranking to develop oil pressure.

Moses

[jordan89oak]

Hey Moses,

I’m back for a quick update. Unfortunately, I still haven’t fired the Jeep up, but I am close to it. Midterms have kept me busy, so very little time for the Jeep. Thank you for the tip on where to get the power for cranking and hot at when on. I will definitely be running a relay (Painless# 50102), and that will require a switched power source. The painless fuel pump relay kit is great, as the wires are clearly labeled as to where they go.

There will be a switch that will allow me to prime the fuel system before starting. I read in a Hot Rod article that a reading of 6 psi should be enough to get the pump going.

I spent some time working on the wiring this weekend. I got the alternator and distributor wired. The only thing that is left is wiring the fuel pump. That’s going to be some work because I want to drop the tank and replace all hoses up there. 

As you can see in the pictures, I’ve only painted half of the firewall. I have a YJ booster and master coming in, so I will paint the other half when that comes in. I know, I should’ve painted it while the engine was out, but I would have never got the engine and tranny in, had I waited. 
 

The carb adapter that I purchased was for a 32/36 Weber, and I have a 38DGES, so I had to port the adapter out for it. This was my first time doing something like this, and I am happy with the results. I mocked up the carb to see how I’ll have to route the throttle cable and that shouldn’t take too long to work on. I will have to make a bracket for that using the OE 4.0 throttle cable bracket.

There is still some work to the harness that needs to be done, as I am going for a clean look. I was also stuck trying to figure out where some of the wires went, but that’s all figured out. I’m replacing the original plastic wiring loom with a braided loom. 
 

My goal is to get the Jeep running by the end of this week. I will keep updating my progress here for anyone that takes on a project like this in the future. 

[Moses Ludel]

jordan89oak...Good progress!  The porting on the manifold adapter should work, the funneling of both barrels should be effective if the jetting is correct.  Make certain there is enough throttle valve clearance with everything bolted together.  Test the throttle over its full range of travel.  Be certain the throttle plates will not stick open...Use a suitable throttle return spring.  If the Weber has a built-in spring, safeguard with an extra return spring.  You'll want distinct throttle control off-pavement.

You mention fuel pump priming, not a bad idea, being able to shut off the fuel supply at will is a good safety back-up, too.  You will need to use a pressure regulator on the fuel supply line to the carburetor.  Weber carburetors will not tolerate excess fuel pressure.  They operate at lower pressures than most other carburetors.  If you supply too much pressure, it will unseat the float needle and cause flooding and other issues.  There should be PSI details that came with the carburetor.  Get a regulator that will hold pressure at the desired setting.

I trust you earned good results on your midterms!  Keep us posted on the project...

Moses

[CJChris]

Hi all.

Jordan thanks for posting your progress.

I have an 86 CJ7 (4.2L, Dana 300, T-176) and I have a 2001 4.0 with harness, computer, sensors, everything I want.  My friend owns the wrecking yard.

I want to use the engine pretty much as is in the Wrangler.

Thanks to your work, I know I need to try to retain the front engines components and MPI system.  

I looked at FSM for 2003 Wrangle and the list of things I came up with that attach to PCM does not look daunting.  Anti-lock brakes, Power Steering Switch (not used on 4.0 wranglers), Airbags do not tie to PCM

Moses, have you come across anyone since April that has done this?   

[CJChris]

Sorry did not finish...

Speed sensor, looks like the Hesco will work with its 3 wire connector.

Clutch Pedal switch, I will fabricate a switch and mount.

Cruise control,  no provision on CJ7  and when its not in use on the Wrangler there is no interaction with the PCM.

In general, these subsystems do not interact with PCM unless they are is use/active....i believe.

[jordan89oak]

Hi CJChris,

 

I am glad that you were able to find this information useful. That was my purpose for creating this thread, as there was very little, to none, information that I could find on the subject. I think that the Grand Cherokee 4.0 is the only block that needs to be cut where the driver's side motor mount goes to, so hopefully you won't need to do that on the Wrangler block.

[CJChris]

I was concerned with the the mounts per your work but did not realize you were dealing with a Grand Cherokee.  Once I get the motor I will report if it is the same.

[Moses Ludel]

Glad you joined this exchange, CJChris.  There should be a growing need for the information, as the 2000-up C-O-P engines and Grand Cherokee inline 4.0L engines through 2004 are increasingly available.  I'm pleased that jordan89oak started this topic and brought late inline six features to light.  Your follow-up details on the late Wrangler engines should be helpful, too.

As for mating late chassis wiring to earlier vehicles, the bigger obstacles are anti-theft/security measures that involve the steering column and PCM.  This came up years ago when the 2.8L CRD diesel from the 2005/06 KJ Liberty was a target for CJ and Wrangler swaps.  The idea followed the export Wrangler concept.  Installers quickly discovered that the key interlock security system in the Liberty created wiring and PCM issues.  KJ steering columns, PCMs and wiring harnesses were allegedly needed for the swap.  Perhaps there were simpler workarounds.

If you're handy with FSM wiring schematics, there should be easier workarounds for your late TJ Wrangler 4.0L swap into a CJ7.  The HESCO wiring harness seems an easier route, though the original HESCO harnesses worked with the 60-way PCM (1991-95 style).  Please let us know whether that harness is worthwhile for your swap.  Many use the donor engine's PCM and harnesses, working their way through splices and chassis hook-ups.  

For any splices involving PCM wiring circuits, I always use rosin core solder and twist splices as illustrated in the 4.0L era FSMs.  Several layers or thicker heat shrink can be used for insulation.  Any more, I avoid crimp connectors for electrical work beyond utility trailer lighting.  (Even there, I use weather-tight, heat shrink end connectors.)  You need moisture proof connections that do not create resistance issues.  Crimp connectors are ohms resistance troubles in the making.

Moses

[jordan89oak]

Ok, I'm back for another update on the Jeep. I finally got the suspension figured out and have gone back to working under the hood of the Jeep. My CJ is a manual brake Jeep, so I purchased a conversion dual diaphragm booster/master combo. I mocked things up today and found some interference issues, so now I will have to figure this out. Being that the intake manifold on the '04 4.0 sticks out further, I will have to figure out a way to connect the throttle bracket and make things work. 

Another thing I did was to drill the hole in the firewall for the clutch master cylinder, as I am converting over to a hydraulic setup. I have the clutch master cylinder mocked up and have marked the pedal to drill a hole for the pin.

Maybe if I would have gone with the slim single diaphragm 9" booster would have more room for the throttle cable. As you can see from the pictures, the dual diaphragm booster sticks out too much and barely clears the air filter assembly, and really leaves little room around the throttle bracket area. I tried turning the carb, but the linkage hits the booster and won't even sit on the adapter. I might just have to get a new manual master and install it just so I can finally drive the Jeep. 

 

[Moses Ludel]

jordan89oak...This is valuable insight for others doing a power brake conversion.  The intake does stick out, visible in your third photo.  The booster size could also impact a V-8 swap. 

There's been plenty of push-back on this project, but your finish line is within sight.  Weather's been hot, sadly there is heavy smoke from the Dixie Fire on both sides of the Sierra Range.  Any Sierra trips will be in the early fall this year.  You should be up and running by then.

Moses

[jordan89oak]

I'm back for a quick update. I picked up a dual fan contour setup for the CJ and finally got around to installing and doing the wiring. The contour fan fits like a glove and was really easy to mount. After doing some research, I picked up a Volvo fan relay, BMW dual temp fan switch, and connectors. This really was a trip trying to sort all of these different components from different manufacturers, but it will make for a much cleaner installation. 

As for the hydraulic clutch conversion, I have mocked things up and got the pedal drilled out for the clutch master cylinder rod. I still have to do some trimming on the pedal to get things aligned perfectly, but things are moving and seem to be going well. I used all OE style components for the conversion. The only thing that I will have to tweak a bit will be the hydraulic line, which is not much. 

When I purchased the Jeep, the previous owner threw in a Warn M8000 winch that had a stuck engagement lever, but he said worked well. I got to taking it apart yesterday to inspect the internal gears and components for a proper rebuild. Before actually installing new parts and seals, I cleaned all of the internal parts up and greased things up for a quick test. The winch works in both directions, so a proper rebuild is in order. I was really excited to see it work, as it sure will save me hundreds of dollars. Plus, a Warn winch on a Jeep just goes hand in hand. One thing I just can't seem to find for the winch are the correct decals. I also installed a new winch plate in the front that is ready for the winch to go on after rebuild.  

As for the power steering system, I got around to installing hoses and was worried that I would not be able to make things work, being that I am using the pump out of the Grand Cherokee. I ended up using both of the original CJ7 hoses (pressure and return) and just ended up bending the pressure line to make it work.

As for the cooling system, I wasn't able to find much information, as people just aren't going with these newer 4.0 blocks for their builds. So, I was stuck trying to figure out the correct lower radiator hose to use for this, as the '04 4.0 water pump has a different outlet from the older 4.0 engines. I went with the '04 Grand Cherokee lower radiator hose. It's not fully installed on there yet, but trimming will be necessary due to it being a bit longer. 

I hope that this is all of help to folks in the future who may be tackling a project like this. 

[Moses Ludel]

You have done a lot of work since you last checked in!  Should be running soon...Wow, the attention to details is obvious! 

The fan brackets on the core support are smart.  Through-the-core plastic mounting ties tear up fins—even worse when the vehicle is twisting off-pavement.  Making sure the Warn winch is in good working order is a safety measure...All this work will pay off when you get rolling...Thanks for sharing!

When you do your final toe-in setting for the front wheel alignment, make sure your uber-steering gear is at its over-center position with the front wheels pointed straight ahead.  You should have good control with that equipment.

[jordan89oak]

Hi Moses,

Happy New Year! I'm back with an update on the CJ7. I finally got to a point where the Jeep was able to fire up and idling for a few seconds. Unfortunately, a few things came up that keep disappointing me.

The biggest upset of it all was the plastic 21 gallon fuel tank. Due to the previous owner drilling a hole through one corner of the tank and another crank in the bank from, what I'm guessing, a rear collision, I tried fixing it. I soldered the plastic tank using a plastic solder iron. I thought it was fixed, even after checking for leaks, but I discovered that it was still leaking when I jacked the Jeep up from the rear this afternoon. I looked for a replacement, but only come across used plastic tanks that cost $350+. 

Needless to say, this is a huge disappointment. This Jeep just continues to disappoint every step of the way. I'm thinking about going the cheap route and installing a fuel cell. 

At least I got to fire it up before discovering the fuel leak. I turned it on with just the header and no exhaust system. I just wanted to hear the engine run to make sure I did things correctly. There was an issue where the electric pump was not activating, but I found another 12v ignition source that got it running. I also initially forgot to prime the fuel system, but right after I fixed these things, it fired right up!

I got the brakes and hydraulic clutch bled, and they feel great. Unfortunately, I did not try shifting it into gear due to me having to shut it off because of an oil leak from the valve cover. I have the wrong valve cover gasket on there. I thought it would work, but it didn't. 

I also discovered that the front driveshaft is too short due to the 4" lift. Even after installing the transfer case drop kit that came with the lift-kit. 

For now, I have set the Jeep aside and will continue it in the future. At least now I know that the '04 Grand Cherokee engine works, and that it will run under its own power.

[Moses Ludel]

jordan89oak...Happy New Year, and thanks for the update.  Many of us have been in suspense.  This CJ-7 continues to be a "project", but you've done so much and are now nearly finished.  I like your use of quality equipment, details like that pressure regulator.  Your high performance car background shows through!  The upgrades to the chassis, steering and powertrain will pay off.

Moses

[jordan89oak]

Thank you! I tried to get rid of the fuel injectors and rails, but I just couldn't find the correct expansion plug size. I tried many different sizes, but nothing worked. I will have to see what I do about the tank. I have to double check to see where exactly it is leaking from. It leaked whenever I raised the rear up, so it may just be the seals around the valves. The tank has to come down either way since I have to mount the new rear bumper.

The engine sounds great! I just have to weld up the exhaust system. I also have to find a way to squeeze a throttle bracket to make things work, but I had to have the power brakes and hydraulic clutch. 

You have been lots of help throughout all of this with lots of great advice. Thank you so much!

[Moses Ludel]

You're welcome jordan89oak...This has been an interesting project based on a utility 4x4 that will deliver years of fun and safe travel when completed.  Your mechanical insight and choices will result in safer, more reliable service in the backcountry.  

We enjoy hearing about your progress, challenges and solutions.  2022 will be the year for this CJ-7!

Moses

[CCrotty]

Moses.  Reading through your thread here, lot's of amazing intel!   I was hoping I could get some advice.  I recently received delivery of an original 1986 CJ7, Laredo.   Frame, body, tub, all in excellent shape.  The trans (5 spd) and motor are shot.  In lieu of rebuild of the 4.2, I was about to go with a I6 4.0.  But reading through this thread, it dawned on me that maybe that shouldn't be the only option I consider.  Looking for some advice here?  I'm also going to upgrade the suspension so any thoughts?  My goal is to make this reliable and modern underneath, so my wife and daughter have no issues using as much as they want! 

[Moses Ludel]

CCrotty...You have a great CJ, the last one in fact.  Your Dana 300 transfer case is a keeper and also works with the front axle's differential offset.  For openers, I would be content with the axles and transfer case and build from there.  A Dana 44 in the front might be warranted if you do very large tires.  You have either the AMC 20 wide track or rarer 1986 Dana 44 at the rear now.  Worth noting which axle although each is durable.  I can quickly identify the axles from a cell phone photo.  Your front axle is a Dana 30 if stock.

For an engine, if you want modern power, I would consider a 4.0L built to 4.6L with your 4.2L crankshaft or a V-8 swap.  Yes, it's often less costly and more gratifying to do a GM LS V-8 conversion and your transmission of choice.  If your wife and daughter prefer an automatic, or if you do, the GM engine with a 4L60E or later 700R4 can be mated to your Dana 300 transfer case.  Our friends at Advance Adapters can provide the adapters, motor mount kit and all.  While this sounds "involved", there is nothing simple or inexpensive about a 4.0L conversion with MPI/EFI, considering the wiring mate-up and all, unless you are very good with splicing recycled OE harnesses.  Either engine approach involves the correct exhaust manifolds, exhaust, fuel supply and cooling details.  While I really like the inline 4.6L for torque, it's not as fuel efficient as a stone stock 5.3L LS V-8.

If you want a manual transmission, I have done the NV4500 heavy duty 5-speed with overdrive and compound low (depicted in my Jeep CJ Rebuilder's Manual:  1972-86, Bentley Publishers), the NV3550, an AX15 and a variety of traditional truck four-speeds like the SM420 or 465, the NP435 and the T-18.  With bona fide iron truck boxes, you can get major gear reduction the easy way:  compound low gear.  What you don't get is overdrive.  This can be a deal breaker with a highway driver and fuel efficiency. 

The NV4500 or AX15 is popular.  The NV4500 would be better if you need a compound low gear and extreme stamina.  The AX15 is lighter yet still plenty strong enough for a stock V-8 to 300 or so horsepower.  Advance Adapters is a North American direct dealer for new and genuine AX15 Aisin transmissions.  This 5-speed aluminum case transmission has a reasonably low but not compound 1st gear ratio plus overdrive.

I would limit the chassis to 4" maximum suspension lift, the amount of lift dictated by tire diameter choice.  I have traditionally cleaved toward 33" diameter, wider tires and wheels.  If you do extensive off-highway rock trails, the 35" or even 37" tires are appealing.  Anything above 31" tires will require axle gearing changes to restore the engine rpm toward stock.  33" tires would likely call for 4.10 gears with a non-overdrive transmission or automatic.  With overdrive, maybe 4.56s.  35" or larger diameter would dictate 4.56:1, 4.88 or 5.13:1 gears, depending upon the transmission type and amount of highway use. 

When making an axle ratio choice, take the tire diameter, final drive gear ratio (include overdrive) and engine rpm into consideration.  I usually target the right engine rpm in high range, top gear at 60 and 65 mph.  The stock Dana 300 has a low range ratio of 2.62:1.  A 4:1 transfer case gear set is available from Advance Adapters if needed for severe off-highway use or massive tires.  As for the V-8 conversions, here's useful information from Advance Adapters:

https://www.advanceadapters.com/tech-vault/1-1980-86-general-engine-conversion-info/

That's a start...There's obviously way more to it, but these are overarching decisions to get the project in motion...Here for your questions or comments.

Moses

[jordan89oak]

Hi Moses,

It's been a long time, but I'm coming back for an update. Although I still haven't been able to drive the Jeep, it is running now. I got busy with a few other things and let the Jeep sit for a few months. 

I finally did some work yesterday and got to fabricating a throttle cable bracket. Being that the booster was in the way, I had to figure out a way to fab a bracket that would keep the throttle cable from interfering with the booster and steering components. 

Since I had the original throttle bracket off of the replacement 4.0, I used that. I ended up using half of that bracket and it worked great. As you can see from the pictures, the cable will drop down from the top. There is enough hood clearance as well. I still have to cut the cable to the correct length, but the hard part is now done. 

I've also created more work for myself now. I picked up a Spartan helical LSD for the D30 and a Yukon LSD for the D44. I'll also be installing a set of 4.56 gears on the Jeep. This will be my first time doing this. I'm waiting on my dial torque wrench and pinion depth tool to get here (should be here by the end of the week). I'll also be making my own setup bearings. 

I hope that my throttle bracket solution is of help to folks in the future. I looked everywhere for a solution to this problem, and finally decided to try it on my own. Sorry in advance for my horrible picture editing skills. I used those two pieces to make my adjustable bracket. 

[Moses Ludel]

jordan89oak...Innovative work on the throttle bracket, good to see your progress...The setup bearings and a pinion depth tool will help considerably during the ring-and-pinion install.  Pinion depth is the most important setting;  the other settings fall into place.

If the current gears are correctly set up, note the pinion gear head markings.  With a Dana pinion mark chart, you will have a reliable means for adjusting the pinion depth between the current gear set and the new gears.  In your case, the pinion markings will help compare or confirm your settings when you use the setup bearings and pinion depth gauge.

Which pinion depth gauge did you choose?  Please share how well it works.  The ring and pinion tooth pattern is your final check.  Follow the guidelines carefully for pinion bearing preload.  If you use a crush sleeve, do not crush the sleeve too far and over-tighten the bearing preload.  (You cannot back the pinion nut off to loosen preload.)  If you over-crush the sleeve, install another new sleeve and set the pinion preload again.   

The crush sleeve must put up high resistance at the backside of the pinion bearing to prevent the pinion nut from backing loose.  Go slowly, in small increments, when crushing the new sleeve with the new pinion nut;  come up to the correct bearing preload without over-tightening.  

This is not an issue with a shimmed outer pinion bearing as long as the pinion nut gets tightened to full torque specification and the pinion bearing preload remains correct.  On shimmed pinion preload axles, you have the pinion depth shim(s) and also the pinion bearing preload shim stack.  On a crush sleeve setup, you only have the pinion depth shim stack and use a new crush sleeve and a new pinion nut (with Loctite for insurance) to set the pinion bearing preload.

Keep us posted!

Moses

[jordan89oak]

Hi Moses,

Thank you for the helpful tips and advise. Being that this will be the first time that I do something like this, any and all advise is much appreciated. 
 

As for the pinion depth tool, I went with the Yukon pinion measuring tool. Purchased it directly from the Randy’s website. They had an incredible deal going on that was too good to pass up on. 

The tool was still a bit pricey, but it will come in handy whenever I do gears or axle builds in my other cars. I will definitely let you know how things go with the tool.

The dial gauge torque wrench should get here tomorrow. 

[Moses Ludel]

jordan89oak...I do value tools, and apparently you do, too!  You stepped up and did the right thing here!  Failsafe and accurate.  Good choice, you'll do plenty of axles to pay for the tool, right?  I trust you still have enough left over for tuition...

Once you have the pinion depth set correctly, the rest is straightforward as I described.  The beauty of this tool set (which mimics the OEM Miller/SPX set I have in my box) is that you will not have to guess about whether the pinion head markings are valid or not.

Exciting...Yea! 

Moses

[jordan89oak]

Hi Moses,

I didn't see your last message, but I have been doing some axles that have paid for the tool already. It has definitely been a great tool to have and makes setting things up a breeze.

Once again, this CJ7 just doesn't want to run though. I went to turn it on two weeks ago (setting timing) and a bunch of black smoke kept coming out. There was a raw fuel smell coming out of the exhaust (open header). I pulled the plugs and saw that they were black and covered in fuel. I was worried it was oil, but it wasn't.

It's strange because my fuel pressure gauge was reading about 1psi, and I tried to adjust the regulator, but nothing changed. I changed the regulator and bought a fitting to put the gauge inline with the fuel line. The pressure would not go up much. This was even after adjustment to the regulator. I'm using a carter P60430 fuel pump. 

So, I checked the float and cleaned the plugs. The float checked out within spec. I turned the Jeep on, and got a bit of smoke that kind of went away. I didn't get to set the timing the last day I worked on it, but I'm hoping to be able to work on it this weekend. 

I've also ordered a new front driveshaft since the old one ended up being short after I installed the lift kit. 

There is still work to be done. Hopefully I can get this CJ squared away and running right soon. 

 

[Moses Ludel]

Hi, jordan89oak...The issue sounds like needle and seat.  The engine was flooding and creating an overrich condition.  This is a Weber, they have a penchant for float/needle issues, the reason for regulating the fuel pressure.  When you removed the air horn/top of the carburetor, was there a normal level of fuel in the bowl?  Or was the bowl overfilled?

While the older Weber standard was a pressure around 1-1/2 to 2 PSI some say these carburetors need 2-1/2 to 3 PSI or even as much as 4 PSI.  Did specs come with the carburetor?  Pressure is volume, so you need enough pressure to provide a steady fuel flow.  However, over-pressurizing will unseat the needle and create a flooding condition.  Follow the Weber guidelines here.

Are you using an OEM CJ-7 style fuel filter with a return line to the gas tank?  This could also be involved.  I would try an OEM 3-pipe fuel filter mounted before the pressure regulator.  Then run the pressure regulator between the OEM (three pipe) filter and the carburetor...Be sure the return line to the tank is unrestricted.  Be sure the EVAP and venting are right.  Make sure you have the correct gas cap in good working condition.  Pressure from within this system (incorrect venting) can also over-pressurize the fuel supply to the carburetor.

Moses

 

[jordan89oak]

Hi Moses,

Thank you for the helpful information. The needle and seat were within spec. When I opened the top of the carb, the bowl was empty. I hadn’t started the engine in a few days. 
 

I realized that the mixture screws were out too much. I’m going to pick up a set of new spark plugs and give it a try. 
 

As for the filter, that’s exactly how I am running it. It is the three-pipe filter. The fuel pump in the rear also has a filter. 
 

The gas cap is new. I’ll have to check for proper sealing there. I’ve tested two different regulators and they both show around 1.5 to 2psi of fuel pressure. 
 

I do remember you mentioning these issues when I first got the Weber carb. For the price, you’d think they would run better. I should’ve, and maybe will, go with a Ford carb like the rest. 
 

I’ll key you updated on the progress. 
 

Thank you Moses. 

[Moses Ludel]

jordan89oak...Make sure the fuel tank vents properly, following the vent design and intent.  If not vented correctly, there could be a vacuum block.  You'd read pressure but not have suction to pick up fuel.  Easy enough to check for flow at the carburetor with the electric fuel pump running.  Run the test fuel hose into a safe can.

The Ford carb you hint about, is that the 2100/2150 series Motorcraft?  These were OEM on 304 and 360 AMC V-8s.  I like the design and dependability, much better than the Holley 2300, which is finnicky and altitude sensitive.  A "universal" Holley 2300 (even the 300 CFM version) can be a chronic tune issue and is not optimal for variations in altitude.  The 304 version of the 2100 would have better CFM flow and not over-fuel the 4.0L engine.

One 2300 Holley that worked well for me on a Jeep 4.2L inline six was the I-H Scout 266 V-8 unit.  In stock, original form (mid- to late-'sixties variety), these carburetors have the right CFM flow, power valve vacuum setting, etc.  Finding an original version could be a challenge.  (If you want the original series number, I have a late-'eighties Holley master catalog that covers all of the OEM Holley applications from the postwar forward.)  This 266 V-8 Holley 2300 carburetor was available in manual and automatic choke versions.

The 2100 Autolite (eventually Motorcraft) carburetors were also popular on Ford small-block V-8s (221, 260, 289 and 302).  That's another OEM tune that would work for a 4.0L Jeep engine.  For tune and jetting, I would seek out an OEM carburetor that originally fit an engine as close as possible to the 4.0L/242 displacement.  A Ford 260 V-8 carburetor would be an example although the "Mustang" application drives up the price.

260/289 V-8 2-barrel carburetors are likely at eBay and swap meets.  For tune sake, make sure any of these vintage carburetors are original and not remanufactured/rebuilt.  The reman industry was notorious for mixing parts, jets and castings.  Externally, these two-barrel carburetors can look the same in small- and big-block applications.  A Ford 360 FE truck V-8 carburetor might look the same as a 302 version.  CFM flow would be entirely different.

In addition to the AMC/Jeep 304 Autolite/Motorcraft 2100 carburetors, there are several other two- and four-barrel OEM carburetor designs that would work, including the 273 Mopar V-8, Buick 231 V-6 and others.  There are vintage Carter, Rochester, Autolite/Motorcraft and Holley OEM applications.  To be clear, none of these vintage carburetors would pass a visual smog inspection on an 'eighties vehicle.  

AMC/Jeep did use the 2100/2150 Motorcraft carburetor as late at 1991 on 360 V-8s in the Grand Wagoneer.  (This carburetor would have way more flow than desirable for a 242 cubic inch six.)  304 V-8 two-barrel Motorcraft carburetors were used into the early 'eighties on Federal emissions CJs, a good CFM match for the 4.0L/242.

Moses 

[DuaneZ]

On 3/11/2021 at 9:18 PM, jordan89oak said:

Hey Moses, 

I am back with an update. So, I was online searching for LS swap components when I came across an the 4.0 efi to carb adapter that I had been looking for all of this time! I know an LSX swap would have been great, but this will save me a lot of time and money. 

The adapter is very well machined. I am going to have to use the original spacer that came with the carburetor, as the throttle linkage hits the adapter plate. This will now allow me to run all of the Grand Cherokee accessory components.

I have to test fit the engine to make sure that it will drop in, being that I had to cut into the driver side mounting tab on the block. If this all goes well, I will start gathering the pieces, slowly, for an LSX swap later down the road.

I will keep you posted with updates.

Jordan

Jordan89oak - can you tell me where you found the 4.0 manifold to carb adapter that worked for you?

[jordan89oak]

6 minutes ago, DuaneZ said:

Jordan89oak - can you tell me where you found the 4.0 manifold to carb adapter that worked for you?

I don't think I can post a direct link, but I purchased it off of ebay. The seller/store is "The Backyard Scrapyard," formerly known as "ecdezz." I don't see the adapter listed in his ebay store, but the seller was great. We exchanged a few messages to improve on the design. He may be willing to make you an adapter.  

[Moses Ludel]

Interesting, Jordan89oak, always good to see your posts...The wild card is whether it's easier to swap an LS V-8 into this chassis than a late 4.0L?  I have dealt with the 4.2L/4.0L block mount issue, it's not a deal breaker.  A light modification to the 4.2L block mount enables the fit-up.  Let us know how this turns out. 

I'm still concerned about your passing emissions with this arrangement.  The year of your CJ chassis would enable a straightforward TBI 305 or 350 V-8 swap (light duty 2WD truck emissions tier, same as your CJ) or an LS if desired.  (LSX?  Well that's not exactly Rubicon Trail material, it's more like sand drags ready.) 

I know you're a fan of the LS engines, and for good reason.  You have experience with that engine family, and an emission legal LS swap is not difficult with aftermarket wiring and other peripherals available.  The kicker for emissions is the cat/exhaust system, which California insists requires all cats that came with the engine donor's chassis.

Here is insight into a 50-State legal LS engine conversion using a later light truck engine and 4L60E transmission.  Steve Roberts and I went into detail on what it takes to be emission legal for California:

https://4wdmechanix.com/moses-ludels-4wd-mechanix-magazine-hd-video-advance-adapters-jeep-tj-wrangler-ls-v-8-conversion/

Howell makes this wiring harness to ease the LS swap process:

https://4wdmechanix.com/howell-introduces-lt1-lt4-wiring-harnesses/

Advance Adapters has the adapters for transmission-to-Dana 300, no big hurdles there.  You can fab motor mounts from a universal GM V-8 motor mount kit.

I did this article on diesel conversions and went into considerable detail on emission legality for California.  The material applies to gasoline engine conversions as well:

https://4wdmechanix.com/cummins-4bt-and-4-isb-diesel-engine-conversions/

See what you think when the 4.0L is running...

Moses

[jordan89oak]

3 hours ago, Moses Ludel said:

Interesting, Jordan89oak, always good to see your posts...The wild card is whether it's easier to swap an LS V-8 into this chassis than a late 4.0L?  I have dealt with the 4.2L/4.0L block mount issue, it's not a deal breaker.  A light modification to the 4.2L block mount enables the fit-up.  Let us know how this turns out. 

I'm still concerned about your passing emissions with this arrangement.  The year of your CJ chassis would enable a straightforward TBI 305 or 350 V-8 swap (light duty 2WD truck emissions tier, same as your CJ) or an LS if desired.  (LSX?  Well that's not exactly Rubicon Trail material, it's more like sand drags ready.) 

I know you're a fan of the LS engines, and for good reason.  You have experience with that engine family, and an emission legal LS swap is not difficult with aftermarket wiring and other peripherals available.  The kicker for emissions is the cat/exhaust system, which California insists requires all cats that came with the engine donor's chassis.

Here is insight into a 50-State legal LS engine conversion using a later light truck engine and 4L60E transmission.  Steve Roberts and I went into detail on what it takes to be emission legal for California:

https://4wdmechanix.com/moses-ludels-4wd-mechanix-magazine-hd-video-advance-adapters-jeep-tj-wrangler-ls-v-8-conversion/

Howell makes this wiring harness to ease the LS swap process:

https://4wdmechanix.com/howell-introduces-lt1-lt4-wiring-harnesses/

Advance Adapters has the adapters for transmission-to-Dana 300, no big hurdles there.  You can fab motor mounts from a universal GM V-8 motor mount kit.

I did this article on diesel conversions and went into considerable detail on emission legality for California.  The material applies to gasoline engine conversions as well:

https://4wdmechanix.com/cummins-4bt-and-4-isb-diesel-engine-conversions/

See what you think when the 4.0L is running...

Moses

Hi Moses! 

It has been a while since I posted, but no major updates. I had to re-clock the distributor and adjust the Weber card. I haven't tried firing it since I did that, but I did pick up a replacement tank (phenolic 20-gallon tank) and installed new valves, valve seals, and sending unit.

The 4.0 motor I dropped in sounds good, even when the timing was off. If anybody does a similar swap in the future, use the older 4.0 intake manifold, as the newer "shoehorn" intake gets very close to the brake booster.

Honestly, I wish I would have just LS swapped it from the beginning. At least a 5.3 LM7 motor with the AX15 transmission that I have sitting in the garage. Keep the motor stock and MPGs wouldn't be too bad. Emissions are an issue, but it would be less headaches. 

I'll hopefully have some updates within the next week or two.

[Moses Ludel]

It's been a grand experiment.  The 5.3L LS often delivers better fuel efficiency than a 4.0L when driven for mileage.  It will be interesting to see where your projects goes from here.  The 4.0L performance is a definite improvement over the 4.2L. (Your 4.2L was worn out, too.)  The 4.2L is best known for bottom end torque, which makes the 4.6L stroker desirable.

I'm undecided which way my '99 XJ will go when the engine needs rebuilding.  Expediency would have me doing a stroker build, keeping all the peripherals as stock as possible (beyond a bump in injectors for more flow).  If time were no issue, you LM7 idea would be great.  Been down the conversion path many times before, not sure whether that's the angle to take on this vehicle.

Looking forward to your updates...

Moses