I can barely believe that a grade 8 bolt is the weakest link in a valve train. If the lifter was locked up or damaged you would surely hear it ticking. Push rod has to be the weakest link. You certainly come up with some challenging engine issues.
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I can break anything I swear. Pushrod was dead straight, and no odd wear patterns on the pushrod, valve stem or either end of the rocker. Just a nice polished spot inside the valve cover where the pushrod had been jumping up and cleaning it by force
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Can you check on equimpment to see and to make sure the hickups are on that cylinder only that the bolt snapped on and not happening on another cylinder?
Bob
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Yes i can pull the plug wire and the engine run exactly the same connected or not showing that cylinder is not co tributing to power made. Could be a cam lobe, lifter, or valve problem. If the woodgas plumbing wasnt in the way so badly it would be simple to hook up a cylinder leak down tester and check the valves and piston rings. I am crossing my fingers that the marvel mmo will loosen something up and that cylinder will come back to life
But in reality this is a high milage motor that does burn some oil, with a unknown service life before I got it. The green trucks motor is sitting a few feet away on standby
Rob brought up a great point as with both my woodgas trucks the oil turns black quickly while running on woodgas. A spinner filter system would be a very valuable asset to oil life, albeit to the tune of about 700$ in added cost. Slinger filters do wonders for keeping oil clean, basically its a inline oil centrifuge that can be removed and cleaned periodically. Thus may be something I look into down the road if funds come available
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Interesting Marcus, i’ve thought about them centrifugal cleaners too, the Scania diesels i mentioned before are all equipped with them (i have one saved for that purpose, or “black diesel” for heating) the ones i worked with are also equipped with a tiny cyclone that separates the thickest part of oil and directs it to the centrifuge.
I believe it was Bendix that introduced them in the fifties.
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On my 95 Jeep Grand Cherokee, the engine was missing at low rpms but if you brought the rpms up it ran a lot better but still was missing a little. Come to find out it was a broken valve spring. It was really hard to see the way it broke. Low compression on that cylinder 60 lbs. Replaced the exhaust valve spring and it ran smooth again no more missing.
Bob
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I did look at the vakve spring while i was in there and it looked fine, didnt see any breaks or cracks in the spring. If it comes down to it and I use the green trucks motor, I would be very tempted to use the obd1 harness and computer, to see if I get the same performance and speeds of Wayne’s truck…
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Oh, so this is a OBD 2 system interesting. So you can change out a OBD 2 over to a OBD 1 on a newer truck. Humm… this opens up more posibilities with newer trucks if this can be done. My 2003 crew cab Dodge Ram with a OBD 1 in it and a lot bigger engine.
Bob
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The beauty in the second generation full size dodge trucks, all harnesses are plug and play.
V10,v8,v6,6bt diesel are all the same truck with 3 wire plugs on the firewall for the engine harness. The v10 from early obd1 (94-95) to obd2 (96-01) are the same truck, same interior harness except a few options on the dash ( radio, heater fan, lights) exterior lighting harness all the same except fender lights on a dually. Plug and play swap from one to another.
The 96 and newer obd2 is tuned from factory for emissions purposes. The 94-95 is unknown, it may have a much more aggressive timing curve since it did not need to meet emmisions standards.
If my only standard to measure against is felt power by how hard my ass is pushed into the seat when I smash the skinny pedal, my 94 would run circles around the 96. The engines are exactly identical in every way. Exact same sensors even. If a guy wanted to i think he could lop the pigtail off with the computer attached and splice it right onto its counterpart
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This is cool, I only thing I can think of is the computerized shifting for the transmission on my truck. Could the OBD 1 do that too.
Bob
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Good question, I have not owned any automatics so im not sure if they used in this time frame a transmission control module or not, this was right in the era of transmission becoming electronically shifted
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I havent read all the post, but i will ask this questain anyway, A compression test should tell if valve burned ir might be leaking.If not, im all ears seeing this fix, maybe needs one head changed. or a vaulve.POSIBLE.
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HI I would say it has not been torqued properly and it has been stretching at every time it is loaded. This has caused fatigue and eventual breakage. I have seen the same on a Cummins L10 engine where a guy fitted a Jacobs brake. It required longer bolts . The guy could not get the specified grade 8 long enough at the time so he got some grade 12.9 allen head cap screws and used them , that was fine . His mistake was that he torqued to the same spec as the std bolts . After some hours use he had a break exactly like that ,which sent the whole engine to lunch .Cause the stronger bolt require a higher torque to get into the critical stretch zone that keeps the bolts tight . it allowe the bolt to work causing the failure
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just to bring this back up as another option, i have recently discovered in 2002 which to my knowledge was the last year of the second gen body style and the last year of the 488ci v10 engine, there was a limited run of the third generation body that received the v10 magnum engine, and even a few into 2003. these have the rear axle pushed further back then the second gen trucks, and would allow for a nice big flatbed. Just today i found local to me a guy with a 2002 third gen bodied v10 parting it out ( extended cab 4wd automatic) and then a 2003 third gen body v10 that needs motor work ( crew cab 4 door 4wd five speed long bed) from what i can find these 2 years of oddball body change that still got the v10 still ran the same jtach obd2 programming in the ecu/pcm that all the 96 and later trucks got. Thats 2 years newer of a truck a fellar could get that wood be woodgas friendly and with the release of the jtach programming last year from hp tuners these trucks can be tuned with all sorts of timing control that will benefit strongly on woodgas, but also throw the emissions out the window to make alllllll sorts of screamin eagles come out the tailpipe on gasoline. Even so that it would improve the gasoline milage that many hated the v10 for having
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I wonder sometimes how many engines transmissions transfer cases axles i have removed replaced and rebuilt over the years. Done it so many times over rhe years i dont think about something being difficult or a pain i just look at hom many hours the book calls for and make it my goal to do it faster then that
About an hout last night, figure an hour tonight and ill have this mill out
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With all that trouble with the dodge, maybe a 454 chevy motor 400 turbo trans, might be enough power too get towing done, i think the parts are easyer tooo get high compresion pistons, and or engine rebuild kits for chevys. my 1991 3500 chevy only gets about 9 MPG average.Would probly do better with 11 to 1 compresion pistons and a carb with a 1 wire distributor…Lot of extra work changing mounts and drive shaft and linkage.Been There 1/2 dozen times, too bad the computors are untrust worthy. Or aint worth the gamble.Money goes fast enough without throughing it out the window on a non garrenteed one.
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What year did you say your broke v10 is with the bad computor
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Not really to much trouble, i still enjoy the work. Big thing is the down time to me, i hate having broken rigs specially one i love driving as much as the dodge. Im actually really looking forward to having the power that felr much better in my 94 and seeing how it reacts to the woodgas compared to the obd2 setup. May find obd1 is a better straightup option if a guy cant afford to do the tuning that will really live’n up this engine. My only regreat at this point is that i didnt swap the engine right off the bat when i got the truck it would have saved a lot of head ache and given me a core motor to start going through
But at this point in life im pretty used to playing musical engines with my rigs 
i used to have a daily driver 2wd toyota that every friday night i would pull the motor and swap it into my 4wd so i could play in the mountains. Sunday night pull and swap it back into the daily driver. Think i did it about 6 or 7 times before i found a good core to rebuild for the wheeler. Still have another 2wd toyota sitting that needs engine work i need to get around to still, plus rebuild the last v8 from the toyota thats laying on the shop floor
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That one is a 96 first year of obd2
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