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I posted a few months ago about transmission options for my CJ-7.  I was leaning toward swapping in an AX-15, but it seems like a pretty pricey and involved swap.  I decided to just get a rebuild kit for my T-5 and get back on the road.  It lasted for 33 years with poor gearing (3.31) and 33" tires for most of it.

Unfortunately, I pulled it out today and found significant side play on what I believe are the input shaft (clutch shaft?) and the main shaft.  I'm going to post a brief video for clarification.  I've been told that the input shaft of this transmission is prone to wear, as it is a two part design.  I'm a complete novice at gearbox work, and I'm hoping to learn something, so fire away.

My primary questions:

1. Is the play seen here normal (I can't imagine it is)?

2. Is this likely to be solved with new bearings, etc. as found in a master rebuild kit?

3. I can get a rebuilt T-5 for $850 or a used AX-15 with the bellhousing from the proper year of TJ for $500.  What would you do?

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60Bubba...For some reason, the short video won't open.  Do you have this in .mp4 or .m4v format?  The story goes that QuickTime is not supported by Apple any longer, not sure whether this is the issue, but .mov is not in my Microsoft Media Play default list.

As for the input counterbore to mainshaft nose end play, you need to check for wear at the counterbore (back end of the input gear) and the front/nose of the mainshaft.  If these parts do not have significant wear, the play on your work bench could be the input gear front bearing wear and the input/clutch gear not being supported at the crankshaft pilot bearing.  

Determine whether the play is real side or radial/lateral movement or simply a rocking at the joining point (counterbore pilot bearing to mainshaft nose).  Causes for rocking between the input gear and mainshaft can be: 1) a worn input gear/front bearing, 2) a worn pilot bearing at the input gear's counterbore, and/or 3) the input gear not being supported at its nose end with play at the bearings.  Start by checking the counterbore I.D. size and the mainshaft's nose diameter.

We'll go from there...Let me know how we can play the video.  I'd like to see the movement you're testing...

Moses

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Moses,

I just got back from a business trip, and I haven't been able to get the video to work in another format.  I did check the shaft play again. There appears to be side to side play at both ends of what is labeled as the clutch shaft. I know this is a two part shaft, is the other end the output shaft?  I assume some of the lateral play is as you said, due to the fact that the end of the clutch shaft where it rides in the pilot bushing isn't supported.

I did detect significant end play when I put pressure on either end of the shaft.  I know there isn't supposed to be any, and I bet I see at least 1/8". 

Tonight I took some pictures with my good camera.  I'm going to upload them here and try to describe what I saw. 

Picture #1: The end of the 1/2 3/4 shift rail has concentric grooves where it rides on the cover. These are very noticeable with a fingernail

Picture #2: Here's the end of the clutch shaft that rides in the pilot bushing.  Not sure if this is healthy or not.

Picture #3: This is the 5th gear shift rail; more wear and rings. I don't THINK the shaft is actually worn as much at appears.  I think both shift rails appear to have been machined to a smaller diameter.  Can you confirm if that is actually the case?

Picture #4: Overall view of the transmission, to my untrained eye, these gears look very good.

Picture #5-8: Closer pictures of the geartrain; again, everything looks pretty good.

Picture #9: 1/2 shift fork has some minor wear.  It's the shiny spot at the bottom of the "U" in the shift fork.

As I've said, I'm way out of my element here, but I want to rebuild this gear box if it's salvageable.  I'm at a loss, because I'm seeing conflicting evidence.  The gears seem to be in very good condition; much better than some I've seen in rebuild videos. On the other hand, these shift rails seem very worn, and the amount of play is alarming.  I have a full rebuild kit, and I'm game to try if you think it's worth the effort.

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Moses/Reid,

I got the videos uploaded to You Tube, so hopefully you can see them now.

 

 

 

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60Bubba...The YouTube videos work very well...The output/mainshaft bearing is shot.  That's the mainshaft's side play at the rear of the main case. Given the amount of wear, assume that the input gear's counterbore (back) bearing or rollers are worn, and the front case/input bearing should be replaced, too.

Your concern at this point is wear at the mainshaft's nose and the input gear's counterbore (the mainshaft pilot bore).  I also see distinct wear at the front bearing retainer, galling from the T/O bearing collar.  Your 1st and 3rd photos:  Is the spring roll pin sheared and allowing the shift fork to move and eat into the rail?  Or is the fork sliding on the rail?

Considering the serious bearing wear, the gears actually look okay in the photos.  I would lay out all of the parts in their order of disassembly and inspect them for wear.  For more comments, take close photos of the gears, shafts and synchronizer pieces.  I would be glad to note the signs of wear and damage.  

We can go from there...

Moses

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Moses,

Thanks as always. I did get a full rebuild kit, and finished disassembly of the input and main shafts today.  I'm a bit stumped as to how to get the countershaft out, or if I should even bother.  It has slight end play, but overall it seems smooth.  

I noticed the the wear on the bearing retainer, and ordered a new one along with the rebuild kit. I was curious what had caused it, but I guess the throw out bearing makes sense.

the leg bone's connected to the knee bone...

I'll put put up some gear pictures when I get them off my phone, but my initial observations are:

1. The synchros seem great.  They still have the rings inside, and they bite down really well, no slipping. Regardless, they're being replaced as part of the rebuild kit.

2. All the slider and gear dog ears seem "pointy" like the new ones I've seen.  

3. The shift rails were actually very smooth where they ride in the bores once I got them apart.  It seems like the design has certain portions machined down to a smaller diameter using a chain saw...

I have a couple stupid questions:

1. Since I have the 4.0 in my CJ, but with the original transmission, I don't know whether I need drivetrain parts for a 258 from a CJ, or for a Cherokee 4.0

Specifically, I want to replace the pilot bushing and throw out bearing.  Also, I'm considering pulling the bell housing to check the clutch and flywheel.  Again, I don't know what parts to shop for. This is one of the down sides to having a FrankenJeep.  If it helps, the transmission has the 10 spline input shaft which I believe was native to the original powertrain.

2. Do you know where to find the input shaft counterbore diameter and the mainshaft nose diameter? I have new needle bearings in the kit, but if the mainshaft and input shaft themselves are shot, I'm better off getting a new or rebuilt transmission based on prices I'm seeing for those two shafts.

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I forgot to ask the most basic question.

this transmission had a little difficulty getting into second gear up or down shifting, so I assumed I had a bad synchro.  Recently, I've started have a LOT of trouble getting the shifter to go into any gear when I come off the highway after an extended 5th gear run,. It would shift back into 5th, but all the other gears felt like they were "blocked out", if that makes sense.

would the bearing wear and associated shaft misalignment cause those symptoms? The synchros seem to be in such good shape, I wonder if this thing has been rebuilt before.

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Yes, 60Bubba...The "stuck in gear" syndrome was definitely related to the shaft misalignment/bearing issues.  Synchros were cocked, not necessarily damaged yet, and parts were binding.  There is also the issue of the front bearing retainer and the clutch release bearing being notchy on the damaged retainer.  Poor clutch disengagement could have been a contributing factor, too.

Lay the transmission parts out in order, photograph them, post photos, and we'll discuss the condition of each part.  Reid's transmission, too.

Moses

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13 hours ago, 60Bubba said:

Moses,

Thanks as always. I did get a full rebuild kit, and finished disassembly of the input and main shafts today.  I'm a bit stumped as to how to get the countershaft out, or if I should even bother.  It has slight end play, but overall it seems smooth.  

I noticed the the wear on the bearing retainer, and ordered a new one along with the rebuild kit. I was curious what had caused it, but I guess the throw out bearing makes sense.

Check the release fork and clutch cover fingers for wear or any possible misalignment of the arm.  Check the release bearing's collar for wear that would cock the bearing on the retainer.

the leg bone's connected to the knee bone...

I'll put put up some gear pictures when I get them off my phone, but my initial observations are:

1. The synchros seem great.  They still have the rings inside, and they bite down really well, no slipping. Regardless, they're being replaced as part of the rebuild kit.

Good sign...If in the kit, might as well replace the bronze rings if the new ones are of good quality.

2. All the slider and gear dog ears seem "pointy" like the new ones I've seen.

Very good sign! 

3. The shift rails were actually very smooth where they ride in the bores once I got them apart.  It seems like the design has certain portions machined down to a smaller diameter using a chain saw...

Makes sense...There is no movement of the fork on the rail, no cause for the rough recessed areas.  Factory rough machining here.

I have a couple stupid questions:

1. Since I have the 4.0 in my CJ, but with the original transmission, I don't know whether I need drivetrain parts for a 258 from a CJ, or for a Cherokee 4.0

There are no "stupid questions".  258 from the CJ era.  The 4.0L block simply bolts to the original drivetrain.  All 258 bellhousing and clutch parts should fit the 4.0L block. However, do confirm/match the clutch parts and note whether this is a 4.2L type clutch.  If there are no notches around the flywheel for a stock 4.0L crankshaft position sensor signal, you have a 258 flywheel.  I know that your EFI is Mopar aftermarket, which should place the crank position sensor and its bracket at the timing cover end.

Specifically, I want to replace the pilot bushing and throw out bearing.  Also, I'm considering pulling the bell housing to check the clutch and flywheel.  Again, I don't know what parts to shop for. This is one of the down sides to having a FrankenJeep.  If it helps, the transmission has the 10 spline input shaft which I believe was native to the original powertrain.

The 10-spline is stock CJ T5.  The flywheel type is easy to spot by the CPS notches or lack of them.  The crank pilot bushing or bearing should be 258 era and match the T5 input nose.  The 4.0L uses the AX15 and a matching metric pilot.  The bushing or bearing in the crankshaft must fit the crank and also the nose of the T5.  Take the pilot bore dimension in the crankshaft and the input nose diameter when making this call.  Also, the nose of the T5 input must center up properly in the crank bushing, and the bushing or bearing must support the shaft's nose properly.

Note:  Always use the same material (either a bushing or a bearing) as the OEM type recommended for the transmission.  The hardness of the input shaft's nose is often different for a bronze bushing than the hardness needed for a caged needle type bearing.  Use the bushing or bearing recommended for the OEM transmission.  Do not use a bearing if the transmission requires a bushing.  An auto supply or online parts catalogs should help clarify the original T5 pilot requirements.  Make sure that both the O.D. (4.0L crankshaft bore) and I.D. (input nose diameter) of your pilot bearing or bushing fit the crankshaft and input nose correctly.  Make sure the nose centers up end-wise in the crank pilot bushing or bearing.

2. Do you know where to find the input shaft counterbore diameter and the mainshaft nose diameter? I have new needle bearings in the kit, but if the mainshaft and input shaft themselves are shot, I'm better off getting a new or rebuilt transmission based on prices I'm seeing for those two shafts.

Take some photos of the input counter bore and the mainshaft nose.  If still measuring round with no signs of grooves, wear or scorching, you likely have reusable shafts.  Install the new roller bearings in the input counter-bore on the bench.  Insert the mainshaft nose and check for radial/side play or runout with the two shafts aligned (parallel and not cocked).  Share photos and dimensions, I'd like to see what you have here.

Moses

 

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Moses,

I just got done with the geartrain disassembly.  I managed to get that counter shaft out with some creative press positioning. No issues noted with that process.

Here are some measurements I just took:

Main shaft nose: .8310 - .8320"  It's smooth and glossy all around, no grooves, nicks or wear

Input shaft counterbore: 1.264 - 1.267"  It also looks clean.  I can even see some very faint cross hatching; old machining marks I assume.

I did smear in some assembly lube and install the new needle bearings to check the shaft in the bore.  It spins smoothly by hand, and I didn't notice much side to side play, though I was of course being very careful and not forcing anything.

For what it's worth, the input shaft nose is .5885"

Here are some gear pics.  I'm afraid I've got things out of order, but I do have that great Tremec manual with all the blow ups. I'll hang it up here after the photos for Reid and others.

By the way, the stupid snap ring on the main shaft slipped when I was removing it.  It actually chipped the splines, as seen in the first picture.  That is a non-bearing surface of the splines.  My plan is to smooth out those splines with a Dremel and a chainsaw sharpening hone I have for it.  Does that seem like a reasonable approach?  The new shaft would be about $340, so I like to reuse if possible.

 

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One other question about clutches: I am looking at clutch kits online and there is everything from $500 Centerforce kits made of unobtanium with unicorn-tear-infused pilot bushings to a LUK kit with clutch, pressure plate, T/O bearing and pilot bushing for $97.  I love that price and the assumption that the parts are all "matched" but is there a price point that is too low to get good quality?  Obvisouly I'm not dealing with high horsepower, but I am doing some aggressive (for me, at least) off-roading, which does put a strain on clutches due to the heat.

Remembering that I have a mechanical linkage, do you have a recommendation for a reasonably priced clutch.  I'm also planning to replace the flywheel if it doesn't look good.  I have no idea if it has been turned already or not, so I don't want to mess with that for the $75 a new one costs.

I also saw an adjustable T/O bearing from Novak.  I wondering if they are worth the extra money...

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60Bubba...Here are my comments about your excellent photos of the T5 pieces.  I'm guessing that there is a sheen on all contact parts, an indication of sufficient lubrication and normal heat exposure.  Some of the photos look "dark", I'm guessing that's just lighting:

5 hours ago, 60Bubba said:

I just got done with the geartrain disassembly.  I managed to get that counter shaft out with some creative press positioning. No issues noted with that process.

Here are some measurements I just took:

Main shaft nose: .8310 - .8320"  It's smooth and glossy all around, no grooves, nicks or wear

The main shaft nose and the nose of the input gear look fine.  Can't see the input counter-bore, but from your description, it sounds like it's in good condition.

Input shaft counterbore: 1.264 - 1.267"  It also looks clean.  I can even see some very faint cross hatching; old machining marks I assume.

Sounds good...All FSM/OEM references are about the fit and not measurements here.  If undamaged and feeling right for minimal (oil clearance) side play, you're fine here.

I did smear in some assembly lube and install the new needle bearings to check the shaft in the bore.  It spins smoothly by hand, and I didn't notice much side to side play, though I was of course being very careful and not forcing anything.

The test that matters...These shafts passed if there is negligible side/radial play at the roller bearing assembly.

For what it's worth, the input shaft nose is .5885"

Looks okay...

Here are some gear pics.  I'm afraid I've got things out of order, but I do have that great Tremec manual with all the blow ups. I'll hang it up here after the photos for Reid and others.

The gears and even the synchro dog teeth on the gears look good.  I'm comfortable with your saving a bundle here and reusing these gears and synchronizer assemblies with new brass synchro rings.  The synchro clutch mechanisms and sleeves look better than typical cores and will offer reliable service.  Synchro keys and springs are in good condition?  Look these parts over carefully, share photos if concerned.  Cheap if you need them, fine if you don't.  New snap rings in the rebuild kit?

By the way, the stupid snap ring on the main shaft slipped when I was removing it.  It actually chipped the splines, as seen in the first picture.  That is a non-bearing surface of the splines.  My plan is to smooth out those splines with a Dremel and a chainsaw sharpening hone I have for it.  Does that seem like a reasonable approach?  The new shaft would be about $340, so I like to reuse if possible.

I would simply touch the chipped spots with the Dremel and hone, just enough to eliminate risk of further chipping/sloughing.  Do not grind these chips smooth, that would reduce snap ring support here.  Don't overheat the metal when grinding, you want adjacent spline material to remain case hardened...The shaft is case hardened, and preventing further slough is sufficient.  I would position the closed portion of the snap ring at these chips, not an open end.  There is plenty of spline material to support the snap ring.  Do not overstretch snap rings when installing them, open the ring just enough to fit over the shaft.

Inspect the shift mechanism to make sure nothing binds or looks sloppy.  You got off well on this unit, the primary damage is bearings, the rest is normal wear and typical renewal parts, nothing drastic.  You have a much better "core" than many rebuilt/exchange transmissions.  All of your gears match up, and that is not guaranteed with rebuilt units.  

The gear teeth should have no damage, your counter gear looks good, including its non-synchromesh reverse teeth...If you follow the FSM steps carefully, the rebuild should produce excellent results.  

The "tricky" assembly areas are the synchro keys and springs at the synchronizer assemblies.  Pay close attention to the way springs and keys must fit, this is crucial to proper function.  The most common trouble after a rebuilding job is at the synchronizer assemblies, usually the wrong positioning of the synchronizer keys, springs and hub sleeves.  Synchro sleeves and hubs only fit one way.  Make sure you use the FSM or Tremec diagrams to confirm the placement and orientation of pieces.

Glad to comment as you move along.  This should be a very reliable unit when completed.  Your photos are helpful to others...Thanks!

Moses

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60Bubba...The LUK kit is cheap enough, though the weak link in these packages is usually the T/O bearing.  Many replacement T/O bearings use plastic.  I would go for a better quality T/O bearing with collar.  Your front bearing retainer on the transmission shows damage, and the collar of the T/O bearing should be new to match the new retainer.  

I have no problem with the LUK clutch cover and disk, though I have always used Centerforce II clutches in my off-pavement and towing vehicles.  If you do not carry heavy loads or rock crawl, a replacement clutch assembly like the LUK would be fine.  

The CJ mechanical clutch linkage has a notorious reputation for parts wear, binding and falling apart under severe off-road driving with frame/body twisting.  Again, if your parts are in good condition and you drive sensibly, this linkage will work.  Inspect the parts and replace worn pivots as needed.

Moses 

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So I was really on the fence about pulling the bellhousing, pressure plate and friction disk.  However, I have a rear main bearing seal leak, and having done one of those on a different 4.0 in the past, I knew how much easier it would be with those parts out of the way.

The clutch really wasn't too bad, but I didn't know what the engine conversion folks did with the flywheel when they replaced the engine and clutch.

Here's what I found:

There are a couple ovoid patches around the pressure plate surface that look like much different than the rest, maybe these are burn marks?  Also, it looks like only part of the diameter of the friction disk was really making contact with the pressure plate.  It seems to have some concentric bands, and what I suppose is glazing, where the disk is shiny.

Have a look at the date stamp on the back of this flywheel.  I guess that speaks to the quality of the OEM parts, though it is certainly in need of service now.  Is resurfacing reasonable here?  I can get an inexpensive flywheel, but I tend to wonder how the quality of an $85 flywheel would stack up against this 33 year old model.  I have no idea how to tel if this one has been machined already.

 

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60Bubba...This flywheel definitely needs resurfacing.  The machine shop should be able to determine whether this 4.2L pre-1991 type has been resurfaced before.  You can often tell whether the flywheel has been surfaced by noting the chamfer shape at the clutch cover threaded holes.  If the flywheel surface has been machined, the chamfer will look shallow or possibly eliminated.

In addition to hard spots and thickness at the face area, another reason for replacing your flywheel would be starter ring tooth damage.  The ring can be replaced on the OE flywheel, talk to the machine shop about this option.  Weigh this against the cost of a new flywheel.  Also ask about flywheel balance when resurfacing the flywheel's face.

19 hours ago, 60Bubba said:

There are a couple ovoid patches around the pressure plate surface that look like much different than the rest, maybe these are burn marks? 

Yes, this clutch pressure plate and flywheel show heat scoring.  If hard spots are too deep, the flywheel may not be a candidate for resurfacing.  The machine shop can make this call.

Also, it looks like only part of the diameter of the friction disk was really making contact with the pressure plate.  It seems to have some concentric bands, and what I suppose is glazing, where the disk is shiny.

Yes, the clutch disk was not making full contact at the flywheel face and pressure plate face.  This is likely due to heat warp, hard spots and an irregular surface.  Worn clutch cover fingers can also cause clutch pressure plate misalignment.  Your damaged bearing retainer and T/O bearing collar wear can create an issue, too.  The wobble at the transmission input gear is a contributor.

Have a look at the date stamp on the back of this flywheel.  I guess that speaks to the quality of the OEM parts, though it is certainly in need of service now.  Is resurfacing reasonable here?  I can get an inexpensive flywheel, but I tend to wonder how the quality of an $85 flywheel would stack up against this 33 year old model.  I have no idea how to tel if this one has been machined already.

If you can salvage the OEM flywheel, do so.  This is a quality flywheel if it can be safely re-surfaced and remain balanced.

You're making good progress.  Good to remove the flywheel and do the rear main seals properly.

Moses

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I did track down a shop that resurfaces flywheels, though it was difficult.  After doing some research, I learned that most now recommend grinding rather than turning a flywheel. The gentleman I found runs a little shop out in the Tennessee Way-back.  He specializes in head work, but he also has a diamond flywheel grinder.  It looked like a giant steel record turntable with a big diamond grinder cup instead of a needle!

We discussed the condition of the flywheel, and he was confident it was in very good condition overall.  He also believed it had not been resurfaced previously.  I'll have to defer to his judgement.  For $25, I think the flywheel looks pretty good.  I suggested and he confirmed I should wash the flywheel in a copious bath of brake parts cleaner after it's mounted.

I did go ahead and order the LuK clutch kit, though I also ordered an all metal throwout bearing from Centerforce.  I should have everything including the main seal and oil pan gasket in time for the long weekend. 

Thanks again for the assistance, and I'll let you know how the transmission reassembly goes.

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My new clutch, throwout bearing and all the rest of the parts arrived this afternoon.  I got all the tricky bits reinstalled on the output shaft, which is the part of this job that was really worrying me.  I have no slop or play, and the sliders and synchros seem to work fine when I manipulate them by hand.

I found this website http://lugnutz65chevystepside.weebly.com/t5-transmission-rebuild.html to be a great help since it shows a rebuild of a non World-Class T5, whereas most of the videos out there are for World Class T5's out of Mustangs, etc.

I'm hoping to button the box back up tonight.

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On 5/25/2016 at 6:10 PM, 60Bubba said:

I did track down a shop that resurfaces flywheels, though it was difficult.  After doing some research, I learned that most now recommend grinding rather than turning a flywheel. The gentleman I found runs a little shop out in the Tennessee Way-back.  He specializes in head work, but he also has a diamond flywheel grinder.  It looked like a giant steel record turntable with a big diamond grinder cup instead of a needle!

Yes, SOP is grinding, as the hard spots are not resistant to the impregnated grinding stone (wet cooled) process.  Traditional "turning" was rough on tooling and often produced poor results around hard spots that were resistant to the tooling.  This is a nice job, in step with contemporary flywheel surfacing.  $25?  Can't beat that one, and the OE/U.S. built flywheel is much better than typical off-shore aftermarket products.

We discussed the condition of the flywheel, and he was confident it was in very good condition overall.  He also believed it had not been resurfaced previously.  I'll have to defer to his judgement.  For $25, I think the flywheel looks pretty good.  I suggested and he confirmed I should wash the flywheel in a copious bath of brake parts cleaner after it's mounted.

Dry before clutch installation is a good idea, no oil residue!  Acetone works well here, too, draws oil out of pores, this is a cast wheel.

I did go ahead and order the LuK clutch kit, though I also ordered an all metal throwout bearing from Centerforce.  I should have everything including the main seal and oil pan gasket in time for the long weekend.

Very good choices!  Happy "work holiday"!

Thanks again for the assistance, and I'll let you know how the transmission reassembly goes.

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60Bubba...Keep the T-5's synchronizer keys and springs in their proper orientation, you're well on your way to a quality rebuild!  A highly productive weekend, you may have time to spare for a countryside cruise on Monday!  Loctite on the hardware, especially the flywheel and clutch cover bolts.  

Are you installing new flywheel and clutch cover bolts?  Use High Strength Loctite (red 271 equivalent) on these fasteners for insurance...Wow, this stuff has gotten expensive!

Moses

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Moses,

The flywheel is back on.  I have some battle damage on my hands from that process, but i got it done.  I reused the old hardware, but I did use some red Loctite gel.

I have run into a work-stoppage parts issue I can't figure out.  The clutch kit I bought for the CJ7 application has a pilot bushing that is about .59 ID and 1.09 OD.  The ID dimension is a match for the transmission input, but the 1.09 OD is about .10 too large for the crank. 

Looking at Cherokee components to match my crank, there seem to only be pilot bearings available.  You mentioned that isn't a good option because of the hardness of the input shaft snout.  Also, those bearings don't list the ID, so I don't know if they would fit the input shaft since the T5 was never native behind the 4.0L. 

I guess I'm seeing the snags of putting in a conversion engine, no matter how similar.  From searching other forums, it seems like most people are getting the larger bushing and having it turned down.  I guess that is an option, but I really haven't found a machine shop locally that is interested in little work like that. 

From looking closely at the pilot bushing I pulled out of the crank, it looks to have been ground down rather roughly.  It fits, but who knows how true it was.  The grinding marks I'm seeing are clearly not from a lathe or any kind of precision machining.  I'm assuming just grinding down the slightly oversize bushing is not a great idea?

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So I did some more research.  My .59 input shaft is 19/32", and the crank bore is 1".  Here is a screen shot of some info on Novak's website.  I also checked Advance, but I didn't find this particular combo.

I ordered the recommended bushing, which should be 1" OD and 19/32" ID.

 

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60Bubba...Good research and parts confirmation...I'd guess that the AX15 is 15mm and 19mm...Did the OE T-5 use a bushing (as opposed to a bearing)?  If so, and if the new bushing is an Oilite material or equivalent, you should be in business.

Use care driving the bushing into place, avoid flaring its end.  Make sure the T-5 input will fit readily into the installed new bushing.  Follow the manufacturer's lube instruction.  If none are provided, use an appropriate grease and pack the back end of the bore/bushing with grease.  Place a light film on the bushing's bore face.  Note that too much grease will prevent the input shaft from fitting properly or make the transmission installation very difficult.  

Footnote:  Grease can be used to remove a pilot bushing from the crankshaft.  If a tight enough fit, forcing an input shaft into a grease-packed bore can actually drive out the bushing!  Drive the old input shaft or an improvised shaft into the grease packed pilot bearing bore.  (A plastic sand head hammer works well with an input shaft, resulting in less risk of damage.  With an improvised shaft of the same diameter as the input gear's nose, a sledge hammer and goggles should work.)  The compressed grease will "hydraulic" the bushing outward as you drive the shaft into the bushing's bore.  This often works much better than a pilot bearing removal tool.

Moses

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Moses,

I wanted to give a quick update on the transmission project.  I was in Japan for a work trip from the beginning of June until last Thursday, but the pilot bushing arrived from Novak while I was gone, so I was able to finish up this weekend.  Getting the transmission installed was a bit of a challenge, but ultimately I got everything in place.  I ended up getting a T/O bearing from Centerforce.  It seemed to be of much better quality than the one that came with the LUK clutch kit.

The transfer case was an absolute beast to install.  95 lbs is just too much to handle manually, so I got a cheap transmission lift from Harbor Freight.  I got everything put back together and drove it around the neighborhood.  Everything drives nicely and I had no leaks.

Now for the bad news: Today I drove it 14 miles to work.  I stopped twice along the way to look for leaks or evidence of other trouble, and all was good.  When I got off the highway, I noticed the oil pressure was low.  This is not unusual for this Jeep.  It has the Cherokee 4.0 HO engine (1995) but an original CJ oil pressure gauge, and I've been told they aren't calibrated the same.  This time, however, the pressure was down around zero and as I waited to go through the guard house to get on the base, I heard a continuous "tock-tock-tock" sound that varied with engine speed and no indicated oil pressure. 

I shut it down at work and checked the oil.  It was a little low, so I topped it off.  I restarted the engine about 4 hours later, and had 20-23 PSI indicated with no strange noise. Within about 1-2 minutes, however, the gauge started bouncing between 15-20 PSI erratically.  It seems to only be when the engine is hot and the oil is thin that the pressure drops to zero. 

One of my coworkers is going to help me tow it home.  I'm not sure what to do next, though I'm planning to get a mechanical oil pressure tester and/or a mechanical oil gauge and see if the in-dash gauge is accurate.  I'd like to believe it's just a bad gauge, but the newly developed "tock" sound doesn't make me optimistic.

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60Bubba...Glad the transmission and clutch work turned out well, good job!

Sounds like we need to discuss this engine situation.  The pressure should be tested with a mechanical oil pressure gauge and the engine completely warmed up.  Don't run the engine to that point if you have reason to suspect that the bearings and lubricated parts are not getting oil!

The aim is first to confirm whether there is oil pressure to the crankshaft bearings and valve train.  Try the mechanical gauge at startup with the engine cold, just the immediate startup test.  Realistically, a 4.0L Jeep inline six should produce at least 30-40 psi at an idle cold, although the "factory" allowance is much lower than this figure:  13 psi at 600 rpm (presumably with the engine warm).  Warm, a 1995 4.0L should produce 37-75 psi at 1600 rpm.  The 37 psi would be minimal and raise concerns.  The AMC inline sixes run higher oil pressure than most engine designs.  The oil pressure relief point is 75 psi.

When you have more details, and if the problem persists, post a new topic on this subject; you can even paste/quote an excerpt from your last post and my reply to save time.  There is nothing in the work you just performed that could cause a drop in engine oil pressure.  There is, however, a tendency for CJ and YJ Jeep oil pressure senders to clog.  The orifice is ridiculously small and typically leads to replacing the sender.  The 4.0L OEM sender performs a bit better but, as you note, is likely not the same ohms range as the OE CJ requirements.  Best to install a CJ type gauge sender that will work with your instrument cluster.  This may require minor fitting adaptation at the block, there are pipe fitting adapters in both U.S. and metric.

Moses   

 

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Very late with this update, but I did verify the engine was making oil pressure.  I installed a new VDO mechanical oil pressure gage and matching voltmeter.  Making about 65 PSI now.  The other weird noise I was hearing I determined to be coming from the throwout bearing when the clutch was depressed, which leads me to the new topic I'm about to post...

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