Moses Ludel

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About Moses Ludel

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  • Birthday June 7

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    http://www.4WDmechanix.com

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    Male
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    Reno Area...Nevada
  • Interests
    Family, destination four-wheeling and dual-sport motorcycling, photography, videography, fly-fishing, anthropology, automotive mechanics and welding/metallurgy.

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  1. CJN8...Lots of work and cost here! Thanks for the photo, you did a very nice clean-up job during the head installation. The pistons look stock by design and should be correct for lower compression ratio. The compression figures you offered earlier, were they before you did cylinder head work or after? The cranking compression was actually within norms from your test figures, certainly not abnormal or high. The smog shop test figures were considerably higher. Between the 14 degree base timing advance and the engine's 175 PSI compression readings, you should hear spark knock/pinging on anything but high octane fuel. Quick questions: 1) Is your cylinder head a 4.2L type or a 4.0L conversion head? (It looks 4.2L in terms of the valve cover bolt holes.) 2) Did you hold the throttle open when performing the compression test? 3) Did you crank enough for "maximum" reading per cylinder? I'm puzzling over the discrepancy between your findings (121 to 137 PSI) and the smog shop's readings of 175 PSI. Which reading is right? If the high cylinder pressure is related to compression ratio, the cause could be smaller combustion chambers than stock 4.2L or the thickness of the head gasket. Combustion chamber volume is different between a 4.2L and 4.0L cylinder head. Milling or surfacing a stock head "too much" would also increase compression ratio by reducing the combustion chamber sizes. "Milling [surfacing] the head" is a time-honored way to boost the compression ratio. The shop that diagnosed the NOX issue seems knowledgeable about the relationship of compression ratio and NOX. The actual factor is heat. Any cause of upper cylinder heat to temperatures above 2500 degrees F will create NOX. An Mopar EFI conversion should, if anything, reduce NOX by more precisely controlling the air/fuel ratio and spark timing. Your base timing sounds too far advanced. If you're trying to relocate the pickup (alter the base timing), you need to shim or space the bracket in a manner that will 1) keep the pickup centered on the damper and 2) move the pickup toward the retard or trailing position. The pickup (CPS) sends a signal to the PCM that the #1 piston is at TDC. To retard the base timing, you want the pickup to index in the retard direction. Basically, you're indicating that TDC is at the retard location. The PCM has no idea whether the pickup lines up with the crankshaft TDC mark for #1 piston or not, it's simply assuming that the pickup sends a TDC signal. (A stock 4.0L CPS is non-adjustable and factory aligned for an exact TDC for #1 cylinder reading.) Confirm the base/idle adjusted timing with your timing light. I would try a new setting at 6 to 8 degrees BTDC. Check the NOX, and if dropping but still too high, retard a bit more. AMC ran the carbureted 4.2L conventional distributor engines between "0" and 4-degrees BTDC at idle with the vacuum advance hose disconnected. You can check the manifold vacuum before and after this timing adjustment. Vacuum should drop as you retard the base timing. When you retard the base timing, you will likely be retarding the entire timing curve, as the 4.0L Mopar PCM relies on MAP and other sensors while not using a knock sensor signal. You've already checked the MAP. You might test the ohms reading at the coolant temp sensor if you have not done that already. Also, the throttle position sensor (TPS) is a fixed setting (non-adjustable) but could be off-voltage. This could cause a rich or lean condition that would affect upper cylinder temperatures. If your CPS fits like William H.'s, lowering the bracket should retard the timing. Try putting flat washers or suitable spacers between the oil pan and backside of the bracket. This will place the bracket/pickup lower and drop the pickup clockwise on the crankshaft damper (when looking at the damper from the front of the engine). Take a timing light reading to confirm that this has retarded the base timing. You may need to elongate the bracket's mounting holes to create "slots" for re-adjusting the gap between the pickup tip and crankshaft damper... Lastly, as a point of interest, the 4.2L engine used an EGR system. The sole purpose of EGR was to recirculate exhaust gases and dilute the incoming air/fuel mixture; EGR cools the upper cylinders to reduce NOX. The 4.0L engine with Mopar MPI (1991-up) does not use EGR, and these engines met even more stringent NOX reduction levels than the 4.2L engines. The Renix EFI 4.0L system (1987-90) did use an EGR to reduce NOX. Your Mopar EFI Conversion kit patterns after Mopar MPI. Moses
  2. zidodcigalah...Your diagnosis may be right: governor or valve body issue. The symptom, however, is that the front and rear clutch are not applying to engage 3rd gear...The governor valve is difficult to access on your TJ Wrangler 32RH; to access the governor valve for repairs, you might as well rebuild the transmission at the same time. However, before I would do anything else, the best diagnostic tool at this point is a transmission pressure gauge test. All test ports on these Chrysler 3-speed automatics are accessible with the transmission in the chassis and oil pan in place. I have taken the time to copy the steps involved in a pressure check and yellow highlighted key points. Note that 3rd gear is the application of the front and rear clutches, so these apply pressures are critical. The actual pressures in each gear, Drive and at the governor need to be verified with a test gauge. This is very helpful for pinpointing trouble. The concern beyond this would be the valve body and a sticky valve(s). The 3rd gear "neutral" sensation that you describe sounds like lack of fluid apply pressure at the front and/or rear clutch. This could be low pump/line pressure, either no or low clutch apply pressure, a sticky governor or a valve body issue. If you have the skill and want to remove, clean and restore the valve body performance, you can also perform the front and rear clutch apply air pressure checks with the valve body removed. Those in-chassis steps are also in the PDF: Jeep 30RH-32RH Pressure Test Diagnostics.pdf There are Chrysler RH/RE transmission survival modifications that I've covered in detail at the magazine. If you go into the valve body, this is also a good time for these upgrades: http://www.4wdmechanix.com/Survival-Upgrades-for-Jeep-and-Dodge-Ram-Automatic-Transmissions?r=1. Moses
  3. Sounds like you nailed it, William! Time to drive the Jeep and keep an eye on things for a bit. Very pleased with your shifting results and the shift detent "feel". Transfer case working well, too...Nice work! Moses
  4. Meticulous shake down, William! The aluminum transmission to crossmember threaded holes are notoriously vulnerable. Yes, a Time-Sert® in stainless steel variety would be the optimal repair; fortunately you can readily access the threads with the transfer case and transmission in place. Some would use a Heli-Coil, less expensive for sure, though you and I know the difference from personal experience. If you lubed the front seal lip with gear lube, this could be the one drop at the bellhousing. You're wise to confirm...Did you use sealant or Loctite at the through hole threads for the front bearing retainer bolts? Moses
  5. Yea, William...Nice job, this looks so "right"!...Thanks for all of the photos! Moses
  6. Rinky Dink...Replacing this cover was the only choice. Do you need the Melling High Volume pump kit, or are you okay with the renewed cover and pump? Stock oil pressure and volume is usually adequate for a stock AMC 304 V-8 engine, especially with a new timing cover (pump "housing"). Good job...best you can do under these circumstances. Moses
  7. CJN8...You can explore and compare head gaskets for thickness although FelPro is usually the same as OEM or allows slightly for milling work, which would make it thicker than stock. How long has this head gasket and engine build been in place? Is there any possibility that the higher compression is from carbon buildup? This is rare with EFI, the whole point to an O2 sensor feedback system is controlled air/fuel ratios, which reduces carbon buildup drastically. The goal with the pickup is spacing between the pickup tip and the crankshaft damper. This should be at least 0.020" gap; William H. shows a 0.050" gap on his Mopar EFI Conversion like yours (see first photo at topic): Make sure the damper runs true and that the gap is adequate for any damper runout. Spacers would be used according to where you want the pickup to position (at TDC, BTDC/advanced or ATDC/retarded) while maintaining the right tip gap. Moses
  8. Should work fine, Case—innovative! You will value this transmission off-pavement. The tire diameter and axle gearing justify the lack of an overdrive gear. Instead, you now have a massively more reliable transmission with the versatility of exceptional reduction gearing...Keep us posted! Moses
  9. CJN8...Yep, that's high compression for the inline sixes, especially a 4.2L in the '80s! Could be a previous rebuild with considerable cylinder head milling, a thin head gasket or higher compression ratio pistons. Retarding the spark timing slightly might help with the NOx issue. The shop likely knows that there is some latitude of adjustment in the Mopar PCM (5 degrees or so). You can also jockey the crankshaft position sensor a bit if it's attached near the front damper in typical Mopar EFI Kit fashion...You must be running higher octane fuel at this compression with a 4.2L cylinder head? Otherwise, I'd expect knock/ping unless the timing is retarded. Here are the OEM part numbers for a 1995 Jeep YJ Wrangler catalytic converter if its available. These should be good numbers for crossover to current offerings: CONVERTER, Catalytic 4.0L Eng. 52017717 1994-95, Federal 52017718 1994-95, Calif. Moses
  10. I'm thrilled! This is how I envisioned the end result...Congrats, Case! Lesley and toddler should be relieved to have you back in their lives. Time to go family (safe) wheeling! You've got extraordinary reduction gearing now, should draw a big smile. Just remember to brake more in low range before downshifting to the lower gears. How did you shorten the retainer end?...Noisier is not uncommon with a truck box, and you're spot on: attenuation with the tunnel cover removed is a huge factor! Break this down in your logical mind as to tone and note. If not grating or grinding, or bearing whining, you likely have nothing more than a very large cluster/counter gear spinning without load in 4th gear. You'll be accustomed to this "real truck" gearbox in no time. I'm curious how you like the T-19 synchromesh in 1st gear? Can you start out effectively in second gear for most highway/street driving? The 1st gear synchromesh is a significant advantage over the T-18 without synchromesh in 1st. Finding this box was a coup. Yea! Moses
  11. Ugh...You're on the right track...Still easier than an intake manifold removal. Maybe the radiator can be professionally rodded and tested at the same time, making the best of the situation? Moses
  12. Alcatraz...Heli-Coil is popular, I used them for years, my first recollection was an aluminum TransDapt bellhousing from J.C. Whitney. An aluminum thread was "soft" out of the box, and Heli-Coil was the fix for the time. In 2007, I came to know Time-Sert® from an automotive machinist at Nevada who was fixing a high performance muscle car big-block that had pulled main bearing cap bolt threads. This is usually the end of the road for a cast iron or aluminum block, but the engine was too rare and had lots of machine work already in place. The Time-Sert® was carbon steel and much stronger than the OE cast block material. The fit was snug, looked great and was permanent, which Heli-Coil is often not, especially for aluminum. I was amazed and later contacted Time-Sert® when I purchased the magazine's Honda XR650R motorcycle used, and it had "soft" wobbly spark plug threads...Time-Sert® to the rescue! Ford Triton engines are notorious for spark plug thread issues. A simple spark plug change can evolve into replacement of the cylinder heads—but not with an over the fender Time-Sert® repair designed specifically for this task! Perhaps Time-Sert steel inserts are what Ford should have done during the construction of the Triton aluminum cylinder heads...Same yardstick applies to other engines, but the Triton spark plug configuration is especially poor. Moses
  13. Alcatraz...If it was the 'sixties that you learned this, we may have had the same teacher! My first professional wrenching job was as a light/medium duty truck fleet mechanic, a role that began in 1968. I also worked at full-service gas stations throughout my high school years (1963-67). The pilot bearing tip surfaced in 1969. Moses
  14. Alcatraz...This would be time for drills and an easy out. Be smack on center with the first/smaller drill bit. Use successively larger drill bits with grease on each one to help prevent filings from dropping into the cooling system if you're drilling all the way through. Leave just enough margin so that the easy out will not chew up the aluminum threads. If the corrosion extends into the threads, there are a couple of repairs, the best though more costly method is use of Time-Sert® inserts, stainless steel in this case. Then there's the common Heli-Coil fix that might be good enough to hold a thermostat housing in place...I just did a video on a Time-Sert® repair/upgrade of aluminum threads; a review of that video may prove useful: http://www.4wdmechanix.com/how-to-time-sert-aluminum-thread-repair-and-upgrade/. Moses