Moses Ludel

Did you vacuum test the actual canister for a leak(s) yet? A simple hand vacuum pump test would be helpful. Vacuum cap all ports but one, then vacuum pump the canister to 20 in/hg or so. Use a pump and gauge that will reliably hold vacuum. Watch for a drop in vacuum. If the drop is rapid, submerge the canister in water with the single nipple/port exposed above the water line, or run a vacuum hose above the waterline and submerge the entire canister. Use an air hose and nozzle with compressor pressure set low—low enough not to blow the vacuum caps off! Watch for bubbles. While we're on the subject of vacuum canisters, there's another canister system that often comes up as a trouble code: The fuel cap at the tank can cause a great deal of mischief and will sometimes throw an emission canister trouble code. For emission control TDCs, the fuel cap issue is easy to test and remedy. Moses

Yep, I'm still thinking of your 2.5L TBI conversion to 2.5L MPI. The two fuel pumps listed in the parts PDFs I provided represent your current pump and the pump you need for MPI...See the content and references to the MJ model pump for 1987 and 1991, respectively. Zoom-in on the illustrations, the electric pump is lower left (item #25) in the 1987-88 illustration. I do have a major concern around the location of the pump module opening in the fuel tanks. From the illustrations, it looks like your '87 has a side mount; the generic drawing for the 1991-up pump shows a topside fit (like the Wrangler) if the drawing is accurate for all applications. I would compare the two MJ Comanche fuel tanks to confirm. If you keep the side mount type, maybe a later pump (MPI type) can be fitted to work with your pump module stand if the fuel tubing size is adequate. Note: There are aftermarket sources for these pumps, and you can change just the pump without replacing the whole module. Hasbro and others make replacement pumps, you need the '91-up version for MPI pressures. Another wild card here is the PCM for 1991 and triggering the fuel pump. You do need the later engine and chassis wiring for the PCM and also verification of which wires run to the fuel tank/pump/gauge sender on a Renix versus Chrysler (1991-up) system. Compare the two wiring systems (1987-90 versus 1991-up), including color coding, wire gauge, etc. Moses

CasualMechanic...Here are two PDFs with illustrations and part numbers for your 1987 MJ and a 1991 MJ. Yours is lower pressure TBI, the '91 is higher pressure MPFI: 1987 Comanche Fuel Tank and Pump.pdf 1991 Comanche Fuel Pump.pdf Zoom in for details and part numbers. This should clarify... Moses

Alberto...If you have a limited slip, friction modifier is usually a requirement. This would be the rear axle, and the differential will have a friction clutch assembly in the middle that you can see with the diff cover removed. There is often a tag on the limited slip axle housing, specifying the need for friction modifier or special lube. Mopar offers the friction modifier, there may be other local sources at Colombia...This is a Spicer automatic locker differential if your Wrangler has it, so you're looking for modifier that serves that type factory locker. The option was not common, you likely have the "open differential", which looks like the front axle's differential...Let us know. As for the rear axle fill plug, your rear axle is definitely a Dana 35. Earlier versions do use a metal fill plug. The front axle is a Dana 30 as you note... Moses

If you can find a "good used" transmission, it should be a $300-$700, I would guess. I generally see "good used" automatic transmissions as an oxymoron. We're talking about a forty year old transmission, with dry seals and unknown wear. Unless your transmission is visibly damaged beyond repair, I would consider removing the transmission and subletting the unit for bench rebuild at a shop. This should be around $1200, maybe a bit more, depending upon hard parts damage. A rebuilt converter is advisable, and this runs an additional $100-$150 as a sublet... Parts are still readily available for these units, and interchangeability of parts would make the original transmission case and adapters the primary proprietary pieces. The I-H engine requires a unique converter housing shape and bolt pattern. If the transmission case, output shaft and tailhousing/transfer case adapter are intact and reusable, rebuilding your unit is a sensible alternative. These A727 units are not the "$3000-$5000" modern rebuild, a seasoned shop should be pleased to bench build your transmission for a fraction of that cost. Discuss this build with a reputable automatic transmission shop. See if I'm right about the cost. Moses

The usual argument for removing engine driven devices would be an increase in available power. One example would be the power saving water pump that doubles as the alternator for NASCAR vehicles. (Note that a NASCAR vehicle does not have a laundry list of electric power options, and the lighter output alternator merely powers up the electronics, gauges, chassis and engine support devices.) It's not surprising, though, that some would target the mechanical water pump as a parasitic, power robbing device. Let's look at this realistically. Most 3.6L Pentastar engines drive an air conditioning compressor, power steering pump, high output alternator and such, each impacting performance to one degree or another. The engine driven water pump is a critical component with a vital function. In most conventional RWD engine applications, the water pump drives a fan and fan clutch. The actual horsepower loss from driving the water pump is lessened by the use of the fan clutch, a device that has been around since the 1960s. Consider the power drain versus the engine's dependency on the mechanical water pump. An electric water pump would demand more alternator draw, which is a horsepower loss, depending upon the amperage draw. (There is a great example of alternator load in the use of an onboard frequency welder like a Premier Welder. Without a hand throttle, you would easily stall the engine under welding loads.) Not sure what the amperage draw might be on a water pump with the capacity to meet a Pentastar 3.6L engine's gallon-per-minute coolant flow demand under load. This could be determined, though. Let's also consider that an electric water pump is much different than an electric fan system. The electric fan system simply needs to draw enough CFM air flow through a radiator core, it's the radiator's job to dissipate heat and actually cool the engine. A water pump, on the other hand, must run continuously to handle the cooling demands of an IC engine. The liquid cooled IC engine has natural hot spots, and the only way to prevent steam pockets and overheating in these hot areas is to constantly circulate the coolant. During engine warm-up (brief and still allowing some coolant movement), conventional cooling systems might have somewhat less dependency on the mechanical water pump...It's one thing to be dependent on an electric fan, as most engines can stay cool without any fan once vehicle speed reaches 30-40 mph or so. All of this said, and considering the necessary modifications, I personally would not convert a 3.6L Pentastar engine to electric water pump cooling. Unless a company can produce a "kit" that makes this an easy install (including the water pump cavity and coolant distribution adapters, the hoses, mounting brackets, wiring harness, etc.), with backup research showing noticeable gains in power, performance and fuel efficiency, and engine longevity, I don't see much future for electric water pump conversions to fit the JK Wrangler Pentastar engines. I could, however, see an aftermarket water pump manufacturer jumping into this 3.6L V-6 water pump failure issue that you share. If Mopar can't produce a quality pump, others may be able to redesign and improve the 3.6L pump to last. OE pumps like the 4.0L pump often last for 150-200K miles with a serpentine belt drive system. 100-150K miles would certainly be a reasonable target for mechanical pump life. I'd welcome additional facts, arguments and discussion, either for or against the use of an electric water pump...The fan clutch made a dramatic difference in reducing engine load and helping to prevent radiator air blockage at higher road and engine speeds. Let's look for similarly overwhelming reasons to install an electric water pump. As a further concern and consideration, the water pump has a big job to do—under continuous heat and load...How long will it last? Will it survive on the Rubicon Trail under load at a crawl pace, or will the electric water pump require its own cooling system? Moses

I have always liked Mobil synthetic products. However, for our 1999 Jeep XJ Cherokee Dana 30 and Chrysler 8.25" axles with ARB Lockers, I use Mopar 75W-120 synthetic gear lube. I use this same lube in the 9.25" and 11.5" AAM axles in the 2005 Ram 3500 4WD truck. 75W-90 synthetic would also work well in either of these applications, though I prefer the 120W equivalent protection during our extreme high desert summers. I agree with nbruno about Mobil 1 gear lube, too. Whatever is readily available in your area would work. One caution with any synthetic conversion on a high mileage axle: The "false seals", actually varnish, on the pinion and axle shaft seals can wash out from the high lubricity and viscosity of better synthetic lubes. Seals begin to leak... I use synthetic lube on newer units and axles I rebuild. Use your judgment if the Wrangler looks like it still has original (25 year old) OE seals. If the lube looks and smells like conventional 75W-90 or straight 90W gear lube, I would stay with conventional oil until you either reseal or rebuild the axles. You could use a quality 75W-110, 85W-120 or other viscosity variations—but use the conventional, non-synthetic gear lube version for now. My view... Moses

First, welcome to the forums, Stainlessman...We look forward to your thoughtful comments and questions! Your AX5 conversion to an external slave looks well underway. It should be helpful to see the relationship of parts and the differences between your '87 internal slave/release bearing and the replacement external slave system. This parts PDF with illustrations will move the process fast forward and provide interchange part numbers: AX5 External Slave.pdf In an overview, you're looking at the master cylinder, slave unit (external), the hydraulic line, the release arm, bellhousing, release pivot ball and, as you hint, the sealing grommets and tin ware. Yes, you also need the front bearing retainer for an external slave cylinder AX5 transmission...Zoom-in on the illustrations and see the part numbers, too. Some of these pieces may be available either aftermarket or NOS. Helps to have the part numbers and an orientation. The master and slave for the OE external unit was one piece/part number. The aftermarket may be able to provide separate pieces and a line. This is brake grade if it comes to fabricating the line, double-flare ends where needed and such. We can pick it up from here... Moses

Roger, welcome to the forums! Happy to jump into your oil priming issue... Most remove the distributor and prime the oil pump with a drive key or appropriate tool and a drill motor. The reason is clear: Simply priming or filling the oil pump with oil will only create faster pickup of oil at the pump; this will not "prime" the lubrication system. If you do remove the distributor and spin the oil pump with the oil pan in place and motor oil in the pan, the pump will pick up prime then flow this oil into the lubrication system via the oil filter stand, the oil filter and the oil passageways within the engine. There is an alternative; however, it's more costly and typically used by shops that do a lot of engine work. This solution is an oil priming tank. You place a suitable amount of oil into the clean tank, pressurize the tank with compressed air, and flow the oil into an engine block oil gallery plug hole. If you select the right gallery plug for priming, the oil will charge the lifters, reach the cylinder head, crankshaft bearings and camshaft bearings, even flowing backward toward the filter and pump. The idea is to have all lines charged for the initial engine startup, leaving no dry or lube-less areas in the oiling system. Note: Here is a Melling oil priming tank and more details: http://www.melling.c...e/Pre-Lube-Tank. I have a tank like this, purchased from Goodson Tools several years ago, and have used it on conventional engine rebuilds, vintage engine restorations and performance engine builds. I would take the time to drive the oil pump through the distributor drive opening. To begin, rotate the crankshaft in its normal direction of rotation and bring it just to TDC on the compression stroke. Remove the distributor cap and note the rotor position carefully. Mark the rotor's position in relationship to the distributor housing. Note: I use yellow auto parts marker and place this mark at the distributor housing's cap seat. The mark should be centered with the rotor's tip and easy to identify later. The distributor housing base has an indexing slot, but to be careful, mark a line at the distributor housing base and engine block. Once the distributor housing to block position is marked, you can remove the distributor. Do not rotate the crankshaft with the distributor removed. You can install the distributor in the correct position later, with the rotor tip in correct alignment with the housing. Now, you can drive the oil pump (crankcase filled to normal level with fresh oil), using an appropriate pump drive tool and drill motor. I like to use a 1/2" heavier duty drill for this job, one that can center over the distributor hole in the block. Carefully drive the oil pump. If the pump pickup screen is properly positioned in the oil pan, the oil should pick up quickly. If possible, use a slow drill speed for this task to prevent galling the pump gears during the oil pickup phase. Caution: Always make sure the lifters, pushrods and rocker arms are in position before charging/priming the oiling system. Otherwise, the lifters can overfill and extend the lifter plungers too far. Tip: For those having difficulty finding an AMC/Jeep oil priming drive tool, consider this option: Fabricate a tool from an old 4.0L distributor. Remove the distributor's drive gear and the accessible electronic parts. Use the old distributor's housing to keep the shaft on center with the oil pump drive. (Clean all parts thoroughly before inserting them in your engine!) The distributor shaft—with the drive gear removed—can be driven by a variable speed 1/2" drill motor. Attach the drill where the rotor would normally fit. Oil the shaft as necessary during the priming operation. Carefully keep the drill on center with the distributor shaft . (Again, the drive gear must be removed from the distributor shaft!) Keep the shaft engaged with the oil pump drive to prevent damaging the oil pump drive. Use a slow drill speed to help keep parts aligned. Once oil is flowing through the pump and system (oil filter must be in place), you will hear the drill load increase. It's helpful to place an oil pressure gauge on the system to monitor the oil pressure, or use the factory oil pressure gauge at the dash. Warning: Do not crank the engine when activating the dash oil pressure gauge! Carefully turn the key to just the 'On' position. Avoid the 'Start/Cranking' position! As the drill motor charges the oiling system, the oil pressure can be read on the dash gauge by a second person. When oil has sufficiently charged the system, the crankshaft and camshaft/lifter areas will have oil. You can now install the distributor, using the rotor position to determine which drive teeth of the camshaft to engage. Again, do not rotate the crankshaft during this process. If the oil pump will not engage with the distributor's pump drive, simply pull the distributor out of the way and rotate the oil pump shaft slightly. Try again until the distributor drops back into its original housing position with the rotor aligned. Make sure the distributor housing indexes with the engine block and seats properly. If you haven't disturbed the position of the crankshaft and camshaft, you should be right back in original distributor timing. The 4.0L distributor (used through 1999 engines before coil-on-plug) does not have a provision for "adjusting the timing". Once in proper position, the distributor housing should not be moved. Note: On the 1991-up MPI Jeep 4.0L inline sixes, you do not "set" base timing like older engines with a conventional ignition. Crankshaft at TDC on the compression stroke, simply align the rotor/distributor shaft properly with the distributor housing. If the distributor housing is indexed correctly with the engine block, and if the rotor indexes correctly with the housing, spark timing will be referenced from the crankshaft position sensor (CPS) and controlled by the PCM (fuel and spark management computer). Trust this raises your confidence level and inspires oil priming the engine correctly... Moses

Well, I'm partial to the I-H trucks and don't want to prejudice your thinking. These were among the best light trucks built in their era, many would argue the best overall. The truck should have a Chrysler A727 (Torqueflite) transmission, code 13407 or known in I-H vernacular as a "T407" transmission. This is a great unit, and if you're hinting that your skills include automatic transmission rebuilding, the parts are reasonably priced, and this 3-speed automatic is considered a "basic" unit from a rebuilder's standpoint. I've rebuilt these transmissions since they first needed overhaul in the late 'sixties. (The A727 dates to 1962 in Chrysler applications.) Review a factory workshop manual or vintage Motors and Chilton professional grade manuals for details on rebuilding. You could likely part out this truck to a restorer of a similar I-H light truck, some of our members have models with a similar chassis. You'll have to weigh the alternatives and your degree of nostalgia. Restoration can become a very costly proposition if the truck needs excessive attention. Welcome to the forums, happy to talk "I-H" if you have needs...Plenty of tech details in my library! Moses

This is where your sons can help, Rocket Doctor. Optimal photo size for the forums is 800 pixels width. Call this partial payment for the noisy lifters on the 454 and rod hanging out the side of the 350 block... Moses

Rocket Doctor...I've had huge success with Quadrajet carburetors, kitting and 'blueprinting' them, adding a brass float in the process. Despite the complexities and myriad adjustments to properly tune this carburetor, the Q-Jet is the most refined and altitude compensating 4-barrel carburetor ever built. Running on the primaries will deliver respectable fuel efficiency. Aftermarket replacement carburetors require tuning and tweaking, and some are benchmarked for a specific displacement engine. Generic carburetors are troublesome to re-jet and tune. If you have the 454 Quadrajet with its original jets and metering rods, and if it's a Federal design without electronic feedback, be grateful. The NP205 gear drive transfer case might work if the input spline count and shaft length are the same. Flange bolt circle is common. A quick answer would be a call to the Advance Adapters' tech line at 1-800-350-2223. They can quickly note any differences between the Dodge and GM applications for the 205. A gear drive NP205 is, quite frankly, the most rugged OEM transfer case ever built for a light truck. The only other consideration would be an Atlas II from Advance Adapters. The 4-speed Atlas is even more trick. See the magazine's video coverage of both the 2- and 4-speed Atlas designs. Moses

Very glad that we were helpful, let us know how the problem resolves, Robt.! I had a 1950 CJ-3A, purchased in 1969. It was my first Jeep project, though at that time it was more service work than full restoration. Learned a lot and enjoyed that Jeep, it ran with a metal half-cab and topless, an L134 and 12V electrics conversion, roll bar and otherwise stock. Your Jeep sounds fun and functional...Share some photos at the forums Garage Photo Gallery, Robt., we'd all like to see it! Moses

Nice work on that ground circuit, Hobiecat...Regarding your gauges and interior light problem, sounds like a connection issue. Do the test of these circuits from the point you know you have current (Power Distribution Box, for example) and trace outward to the device (gauges, interior light socket and so forth) with a volt-ohmmeter and continuity test...To save time, check for continuity over long wiring circuits then narrow it down to where a circuit is "open". Don't rule out simple items like fuses at the Power Box... The gauge connector behind the instrument panel is a known issue on the TJ and XJ Cherokee, and there are other electrical gremlins with the TJ Wrangler. I did a magazine article on the connector fix for the gauges on an XJ Cherokee. Some TJ Wranglers suffer the same fate, and often, just an unplug and re-plug after cleaning contacts with Mopar electrical cleaner is enough to get the connector to behave. Otherwise, here's the XJ Cherokee fix, which is similar to the Wrangler: http://www.4wdmechanix.com/How-to-XJ-Cherokee-Erratic-Gauges-Fix.html. The gauge connector is a possibility; however, on an '06 model, I'd look for a much simpler fix first. Any aftermarket installations like a sound system, add-on lighting or an alarm system? These can often be a source of trouble due to poor connections or bad splicing of wires. On a vehicle as new as yours, I'd look closely at anything added aftermarket that could interrupt circuits or create shorts and opens in the electrical circuits. Talking about splices, I recently heard of a unique way to moisture proof wire splices. I'll throw this out there for use where practical. The suggestion came from a retired electronics specialist and AT&T wire splicer: 1) Make a clean strip of each wire end and overlap the two wires with ends facing toward each other—think butt connection without the butt connector. 2) Place heat shrink well up the wire, away from soldering heat, for use after soldering the two wires together. 3) Solder the wires with rosin core solder or rosin flux and solder for electrical connections. 4) Take a heat glue gun and run a thin, even bead of hot glue over the soldered joint. Allow to cool. 5) Place the heat shrink tubing in position over the soldered and glue-coated joint; shrink down the tubing for a good seal. The hot glue, once cooled, forms a barrier that resists corrosion wicking up the wires' insulation. (Corrosion is otherwise hidden beneath the heat shrink tubing.) On critical circuits like EFI PCM wires and for electronic modules that are hypersensitive to voltage fluctuations and ohms resistance, this anti-corrosive barrier would be better than heat shrink tubing alone. Something to consider... Moses

This is the place for questions, Robt. Welcome to the forums! You could post at our Jeep Wrangler forum, however, this will do. There are some generic, useful concerns here... RareCJ8 posed a basic concern, that the fuel filter must be installed with the flow in the correct direction. It must also be the correct filter for your YJ Wrangler's fuel system, MPI/EFI requires a fuel filter with a specific pressure rating. If the filter is aftermarket, make sure the part number is a direct replacement for the Mopar OE filter. Your fuel injection system should operate near a maximum of 39 PSI. This is with the vacuum line disconnected to the fuel regulator at the injection rail and the engine idling. Connect the vacuum line, and pressure with the engine idling should be 31 PSI. The difference is for cranking pressure while starting the engine. Maximum pressure at the injection rail, under any circumstances, should always be less than 45 PSI. Warning: The maximum dead headed pressure from your 1992 YJ fuel pump is around 75 PSI and should not be tested for more than two seconds. Use extreme care with gasoline under this high pressure, wear protective goggles and keep gasoline away from hot spots! The regulator on your two-pipe MPI/EFI system returns excess fuel to the tank. If there is a restriction in the return line, fuel pressure would be high, and if the regulator is defective, that could cause a restriction. I'd be more inclined to think return line restriction; these regulators seldom stick shut, more often they hang open. A pressure check of the fuel pressure can be readily done with the proper gauge at the Schrader valve on the fuel rail (at the engine). This valve is easy to spot on the fuel rail, it looks like a metal valve stem for a wheel/tire. You might want to check the pressure to see if that could be causing your fuel leak. I copied a view of the fuel lines and filter for your '92 YJ Wrangler. You can review the illustrations and parts to see whether something is out of sorts with your system. The hoses must be in top shape and have high pressure EFI gasoline rating. Clamps should be EFI grade. I like the European style with the overlapping band and a screw/nut tightening provision. You can specify these clamps at NAPA and elsewhere, they are commonly known as EFI fuel hose grade. Your fuel hoses at the filter should be rated well in excess of 50 PSI, the higher rating, the safer. Here is a PDF with illustrations and part numbers for your fuel lines and filter. You can zoom-in for details and Mopar part numbers. Your model is a Wrangler "YJ": 1992 YJ Wrangler Fuel Filter and Lines Diagram.pdf Try the fuel pressure test at the fuel rail. Make sure your fuel filter and lines to the regulator are not restricted and that fuel flows readily. (Please observe my warning about high pressure and gasoline!)...Make sure the return line is not restricted and that it dumps excess fuel into the tank. You can get an inexpensive fuel test gauge kit from Harbor Freight and others. If you plan to make a career out of fuel pressure testing, you'll want a better grade test gauge. Moses

Good work, Biggman100! The harness and connector differences could reflect the emergence of OBD-II. With Jeep, the 4.0L XJ Cherokee had a wild-card year: 1996. The transition to OBD-II was awkward, and the engine wiring, wiring harnesses and connectors for 1996 are often unique to the 1996 XJ. In the case of the Wrangler, we can note that there was not a 1996 model made! This likely was to keep the 1995 YJ Wrangler and its non-OBD-II emissions alive while the 1997 TJ Wrangler emerged with the new OBD-II PCM, wiring harnesses and other accommodations. There may also have been a "transition" for the 1996/97 Dakota and Ram trucks as they moved into OBD-II requirements mandated for the 1996 model year...In any case, your findings are very useful! Thanks...Moses

That's interesting about the 5.2L heads. According to the 2010-2011 Mopar Reman catalog, they use the same cylinder head part number from 1992-2003. Part number R5852480 fits all 5.2L Magnum engines. Presumably, these heads are rebuilt from OE cores, and they come without the rocker arms or head gasket. If rebuilt/exchange, Mopar will accept and rebuild any of these cores and send them out to fit atop any 1992-2003 short engines. Note: There are instances where a manufacturer will sell a "universal" replacement head that interchanges or supersedes with several earlier casting numbers. These heads would be "crossover" designs that bridge the changes in head and manifold design over the years. Sometimes, a "remanufactured" head is actually a brand new, universal replacement type head casting. The best way to compare cylinder and block castings is by actual casting numbers on the cores—period. An automotive machine shop's guide to casting numbers will break out the year and application. If the Mopar Reman catalog is accurate about the 5.2L V-8 heads fitting from 1992-2003, then your theory about the intake manifold must be the concern. The intake manifold gaskets might accommodate changes in the manifold design: port sizing, manifold threaded ports for coolant, vacuum or other fittings, gasket improvements, injector fit, added fittings/ports or whatever. (The manifold part numbers for 1996 versus 1997 might provide a clue here.) For cylinder heads and manifolds, casting number comparisons are the best criteria. Regarding for the 3.9L V-6, the 2010-2011 Mopar Reman catalog again shows the 1992-2003 3.9L V-6 Magnum engines in the "Trucks, Vans and Jeep" section as only one cylinder head part number for all of these years: R5639480. This is the 2010-2011 catalog, and unless Mopar has updated the information since (call your local Mopar/Ram dealer parts department or check out an online genuine Mopar parts source), you once again have a cylinder head (minus rocker arms and head gasket) that apparently fits all of these years...unless there is a universal new casting flowing into this parts stream. Note: Since Mopar does require a core on these 3.9L and 5.2L heads, logic suggests that the cores are being rebuilt and shipped out to fit all 1992-2003 short blocks. Unless, of course, there is a universal new casting being used in place of the OE cores. This can occur, and again, the casting numbers are the most reliable way to break out differences in design and applications. If you need the intake manifold part numbers for the 5.2L or 3.9L over the 1992-2003 period, I can look them up... Moses

So, my first approach was a long-block replacement. If you want a direct, complete replacement engine, the differences would be exhaust and emissions pieces and hookups, PCM changes, tuning and sensor settings, exhaust system differences and so forth. The 5.2L roller lifter V-8 engines fit three distinct platforms: Ram truck (1992 MPI engines to as late as 2003, according to Mopar catalogs, we know that 1998 is a reliable cut-off); Jeep Grand Cherokee (1992/93-'98 5.2L V-8); and the 1992-up Dakota 5.2L MPI V-8 pickups. Of course, 4x4 models use different transmissions than 2WD, there are these considerations, too. Note: When a recycler tries to identify direct, complete engine swaps, they rely on interchange manuals. The manuals in recent years must take into account the emissions requirements for an engine swap. In some states, like California, the engine swap cannot involve an engine older than the chassis. That could be the reason they insist that you must use a '94-'95 Dakota engine; for California, it would have to be a complete '95 engine. If you do want a complete engine swap, you're likely left with comparing parts between your engine and the recycled engine(s) being offered. Also, you need to consider whether your emissions inspection will be a problem with an earlier or later engine installation. Newer would be okay, however, states like California consider this a "swap/conversion" and not simply a "replacement". Technically, in California anyway, you would need a referee station inspection and special sticker, even to put a later engine in the chassis. So, there are two big concerns around a complete engine swap: 1) emission legality and inspection, and 2) actual parts interchange. A huge difference is OBD-II (1996-up) versus your 1995 PCM system. 1996 is the first year for OBD-II (self-troubleshooting) computers. Your 1995 chassis does not have OBD-II. This could be a major issue, as your engine and chassis wiring will not interchange with OBD-II sensors, and certainly not with the PCM plugs, and there would be a different type PCM (Chrysler "JTEC") from 1996-up. For a complete engine swap, you may be limited to 1992-1995 engines for this reason. Obviously, the best way to play it safe would be a 1995 (maybe '94 as well) Dodge Dakota 5.2L V-8 if you want a complete engine swap. If a long-block or semi-complete engine is feasible, you have many more options. I looked at the 5.2L V-8 long-block listings directly from Mopar Reman: All 1992/93-up 5.2L Jeep and 1992-up 5.2L Dodge Truck roller lifter engines use the same long block part number through 2003. (Cylinder heads are interchangeable for all 1992-2003 5.2L MPI engines.) Clearly, the Jeep Grand Cherokee 1992/93-98 and Dodge Truck 1992-2003 have interchangeable long-engines and parts. Note: 1985-90 roller lifter long blocks interchange with each other but not later. 1991 is a "mystery" or transition year. Truck 5.2L V-8s still use TBI in 1991. This means that the manifolds, injection, distributor, water pump and all other peripherals may have differences, but the basic 5.2L V-8 long engine is the same from 1992-up. If you were to replace just your long block and use all of your existing 1995 peripherals, you would have a wide cohort of 1992-2003 5.2L pushrod V-8 engines as a source. Moses

Hi, Biggman100...I understand the decision to simplify the restoration of the '95 V-8 model 4x4 Dakota. Sticking with the current setup and an automatic transmission will make your engine replacement much easier. First, I would keep the current induction and exhaust system to simplify the engine change. As for what 5.2L will fit, consider any truck/SUV 1992-98 5.2L Mopar pushrod long-block as a replacement. A long block simply needs to accept the peripheral parts, and the Dakota long block is similar to a Ram truck or Jeep Grand Cherokee. The 1991 Ram truck engines with MPI/EFI may also meet this fit. As long as you maintain the existing induction/injection, exhaust and ignition system, you will just swap over any details like the oil filter stand, water pump or fan and clutch, etc. Unless the '95 Dakota 4x4 V-8 does not have all of its pieces in place, this should not be a challenging engine replacement. If you elect to use the 5.9L, we could compare PCM and other details to see if additional components need to be included. Possibly not, as the injectors are the same for both engines. PCM and other pieces might also be the same or at least work interchangeably. Should you need specific part numbers, I can furnish details for a Mopar long block replacement into a 1995 Dakota, including any additional interchange parts guidelines. Moses

You're very welcome, Alberto. These kinds of issues come up frequently for restorers of the 1981-90 Jeep CJ and YJ Wrangler models with the 4.2L inline six-cylinder engine. In the U.S., it is often a state-required emission inspection that turns up the "troubles" with the emissions and fuel system...I trust that the information provided in the PDF will help you and many other Jeep members and guests at these forums. Colombia must be a wonderful country for four-wheel drive access. You mention "3000 meters" elevation, and that is much like the Sierra Nevada Mountains near our home. Snow, permanent snow packs on the north slopes, this can be great country. At Colombia, you have access to the Pacific Ocean, the Caribbean Sea, Ecuador, Panama, Venezuela, Peru and Brazil! Lots of rivers and mountains, too. I imagine that the magazine's Honda XR650R dirt motorcycle would be a great way to explore Colombia. Photos would be great with your Jeep at these kinds of backdrops...Please share photos when you can. Enjoy your 1989 Wrangler Sahara, Alberto. Moses

In the U.S., NAPA retail auto parts stores have always been helpful. Car Quest also has extensive catalogs of individual parts. NAPA's Echlin line and catalogs are a good source. Do you have retail chain stores like these in Colombia? Is there an AC/Delco, Motorcraft or Bosch warehouse? These would all be sources for the more generic parts like check valves and vacuum delay valves. Otherwise, your best source, and many do this in the U.S. with older engines and emission control parts, would be recycling yards ("wrecking yards") that have older Jeep vehicles for dismantling and used parts sales. The vacuum hoses should be the easiest items to find, as these hoses are "universal" and come in specific sizes for the diameter of the vacuum nipples and pipes. A vernier caliper (even an inexpensive plastic one) is helpful for determining the correct diameter needed. You want the hose to fit snugly on the pipe or vacuum nipple, so some experimenting with samples of vacuum line would be helpful. In the PDF I have provided below, the Mopar listings show actual vacuum and fuel hose sizes for the various locations on your engine and vehicle. These measurements are for bulk hose that you can buy locally. To save you a great deal of time on your Jeep 4.2L Wrangler project, I combed through the factory Mopar parts catalogs for your model era. I gleaned out pages that provide both detailed illustrations and also the part numbers. You can see the relationship of the parts. Some (very few) of these parts are still available from Chrysler/Mopar. The Mopar part numbers will help you cross-reference to other manufacturers that may still offer the parts. Hose sizes are noted in "I.D." (inside diameter) and shown as "bulk" source. This means they are generic and can be purchased as bulk hose for vacuum or fuel hose in these sizes. Make sure you use hose that is specified as vacuum or fuel grade. Always use fuel-grade hose for fuel lines or for lines exposed to fuel vapors. Your 4.2L Wrangler with carburetion does not require fuel injection rated pressure hose. (If you convert to EFI, you must upgrade the fuel supply line hose for the added fuel pressure.) Note: The fuel tank for your vehicle is either 14.5 or 20 gallon. The 2.5L TBI/EFI engine uses an electric pump in the tank, your 4.2L carbureted engine does not. At the tank, your Jeep has only the fuel gauge module without the electric pump unit. This will speed your search along. Both the PDF text and the images can be "zoomed-in" for great detail. I trust this will make your project much easier. You can determine what you have, what you need and the part numbers for each item. In the page footnotes and model references, Mopar labels your Jeep YJ Wrangler as a type "81". I am unclear whether your vehicle was for U.S. (North America), Canada or the export market. In some cases I provided sets of information for both U.S. and export market vehicles. You will need to compare the illustrations with your vehicle's actual equipment: 4.2L YJ Wrangler Fuel & Emissions Systems.pdf From experience, I know that if you do not have this "big picture" information, the project can become very challenging. With the extensive information provided in the PDF, you will be able to identify the parts you have and those you need. At that point, you can try to source the parts by part numbers or from generic sources. You will discover what is still available as new replacement parts. You will also know the relationship of the parts and how they fit together. I trust this helps, Alberto... Moses

Pleased to share, Forman, thanks for asking! I've done break-in on a variety of engine types and builds and have also seen folks abuse engines during this critical period. Even though the impulse is to "see what it will do", we need to keep in mind that it can make the difference between a long-life engine and one that needs rebuilding again in short order. After riding a bit, you'll have an intuitive sense for the goals here and will find yourself treating the KLR properly during break-in—very soon! Moses

Alberto, you'll find the BBD carburetor step-by-step article at the magazine helpful. The vacuum diagrams, too. As you proceed with the restoration, we can fill in other "factory" details. Since you're willing to do this work, I know that you will be thorough. Each of these systems overlap, and the only "right" way is a restoration to original equipment performance as you suggest...You always have the option of an EFI conversion if you discover that it is cost effective or if you simply cannot find the many parts you need for the restoration. I am pleased with your enthusiasm and believe you will draw the correct conclusions about whether to restore or not, Alberto. Looking forward to pictures of the Jeep. The forums' Garage Photo Gallery would be a good place to share. Moses

Hi, Biggman, great to see your post and learn about the latest acquisition! The manual transmission swap on a '95 Dakota can involve electronic concerns like the PCM, so you'll need to consider how far you want to go with this conversion. The V-8 swap could be a 5.2L or even a 5.9L V-8 from a Ram 1500 or a Dakota (5.2L). There's the option of using the V-8's automatic transmission in the process. The Dakota did offer a 5.2L V-8 in 1995, so there's a prototype here. Regarding the AX15 versus an NV3500 or NV3550 (Jeep version), they offer approximately the same torque rating. Jeep and Dakota use both types, Jeep changing from the AX15 to NV3550 in 2000 models. Interestingly, the Ram and Dakota trucks show an available NV3500 transmission in 1995, so both transmissions were apparently available at that time. The bellhousing-to-transmission pattern for an AX15 or NV3500/3550 is the same. (I adapted a Jeep NV3550 to a Buick V-6 by using a Toyota A150 to Buick V-6 transmission bellhousing adapter.) Both use the "8" shaped bearing retainer. The NV3500 was used behind the 3.9L V-6 and 4.7L V-8 engines. In the Ram 1500, the NV4500 was the transmission of choice, and this iron case monster is light years more stout than the AX15, NV3500 or NV3550. So, if you're serious about a V-8 and manual transmission, the 4.7L would be the limit for the NV3500. An NV4500 can handle up to one-ton truck capacity, including Cummins 5.9L diesel power, and that would be the optimal transmission for the torque of a 5.9L V-8. Something to consider. We can explore this further. I'd emphasize again that the electronics do change between these engine and transmission combinations. That can involve wiring harnesses as well. It might be easier to get a powertrain with a 46RE or other transmission that can line up behind an LA 5.2L or 5.9L pushrod V-8. Electronics might be less challenging, since the Dakota 4x4 did at least use the 5.2L V-8 and an "RE" series automatic transmission in 1995. Sounds like the price is right on the '95 Dakota, and I know you like this model...Several ways to go! We can explore the PCM part numbers and wiring harness numbers. Moses

Building a motorcycle engine for reliable performance begins with careful assembly work. The Honda XR650R project came under the close scrutiny of an HD video camera, and the result is the 49:37-minute streaming video rental at Vimeo On Demand. Following the build, proper break-in of the engine is crucial. During assembly of the XR650R top-engine, care was taken to lubricate critical parts for the initial engine startup. This included lube on the piston pin, rings, valve stems, camshaft, valve tips and timing chain—as illustrated and detailed in the video. Lubeguard Assembly Lube, Permatex Ultra-Slick Assembly Lube and Lucas break-in oil with zinc were each used accordingly. The importance of zinc additive during break-in cannot be overstated. When a cylinder has been honed precisely like the work performed at L.A. Sleeve Company, piston ring seating is less of a concern than the camshaft break-in. Ring seating is still important, and I will describe my technique for ring-to-cylinder wall break-in: To begin, I use a non-synthetic oil that will provide enough friction to actually seat the rings. Synthetic oil often has too much of a protective film to allow necessary friction. After break-in, I will change to full-synthetic oil and dramatically decrease ring wear by providing an extra friction barrier or film between the cylinder wall and rings. Ring seating can be dramatically enhanced by smoothly accelerating the engine and decelerating the engine. Heavy throttle for sustained periods should be avoided for an initial timeframe (at least an hour of operation or 60-100 miles of road use). When you decelerate the engine, the piston rings push out against the cylinder wall. As noted in the video, the top compression ring for the Honda XR650R has a gas ledge machined on its upward facing, inside edge. This raises ring pressure against the cylinder wall, especially during acceleration/deceleration cycles. This increased pressure quickly seats the rings. Caution: A sure way to prevent rings from seating is repeated hard acceleration without any deceleration cycles. Gradual acceleration, limiting peak rpm and regular deceleration cycles get the best results. Camshaft break-in is highly significant. Damage to a new camshaft's lobes during break-in can occur quickly. The absence (deletion) of zinc from current motor oils has made this issue even more critical. (I discuss this at length in response to a Jeep 4.0L flat tappet camshaft and oil question here at the forums, read that information at the topic link.) On the Honda XR650R engine, an aftermarket camshaft from Hot Cams came with very specific instructions on initial startup and break-in. I include those concerns in my camshaft startup and break-in approach: During upper engine assembly, Lucas break-in oil with zinc was added to the oil (poured over the camshaft) prior to startup. The amount used was based on the product's instructions, and I reduced the quantity in proportion to the quantity of oil in the Honda XR650R lubrication system. At the first startup, the engine was run at 2,500 rpm immediately after picking up oil pressure. On the motorcycle lift and strapped upright, the motorcycle's engine was cycled between 2,500-3,000 rpm with a large electric fan in front of the cooling radiators for the first 20 minutes before idling down to 1500 rpm. (I used an infrared thermal gun to monitor cylinder, head and exhaust header heat this entire time.) After the initial 20-minute run on the stand, the initial road/trail miles involve a cycling speed between 1400 rpm (idle) and an estimated maximum of 3,500-4,000 rpm (no tachometer on this dirt bike). I run for 20-30 minutes at a time, varying the road or trail speeds, then cool the engine completely before repeating the cycle. Make sure that your lighter on-road or on-trail use provides sufficient cooling air to the radiators and cylinder. Earlier morning or cooler evening rides are helpful. Avoid idling for extended periods, and avoid over-revving the engine. I avoid redline shifts for at least the first 100-150 miles or 1.5-2 hours of operation. Considering the operating speeds for a four-stroke motorcycle engine compared to an automotive engine, three hours (approximately 200 miles) of concentrated effort to break-in the camshaft properly should be sufficient. Rings should be sufficiently seated now...At this point, the oil should be drained warm and thoroughly; I switch to synthetic oil now. Note: During this oil change on the XR650R engine, I will remove the frame (down tube) oil screen (not the inside-engine screen) for inspection and cleaning. A new oil filter is mandatory; inspect the removed oil filter for unusual debris. In the road test video, I'm on the throttle but not redlining. I don't baby (never "lug") or abuse (do not over-rev or throttle hard) an engine during break-in. Constantly monitor engine temperature and avoid overheating or extensive idling. The Honda XR650R showed no signs of "blue smoke" (ring blowby or valve guide seepage) from the very first start onward. You should not see blue smoke or significant oil consumption if the cylinder has been honed properly, the rings were installed correctly and the valve guides are sealing. By 200 miles or 3 hours of operation, a motorcycle engine should have sufficient break-in to no longer be a critical concern. As long as oil consumption (ring blowby) does not occur with the switch to synthetic oil, the engine is ready for reasonably "normal" use—whatever that means for your riding style. For the properly built engine, with correct break-in, a quality synthetic oil will determine the lifespan of the rings, valve guides, timing chain, camshaft, rocker arms, engine bearings, piston/pin, and other critical moving parts. Wear is greatly reduced by the use of synthetic oil. Unlike an automobile or truck engine, wear will be much more significant on a motorcycle engine that operates consistently above 3,000 rpm. Wear is all about piston travel and valve opening events, and synthetic oil can make a difference here. Moses