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Sick Cummins

5822 Views 109 Replies 12 Participants Last post by  char1355
Bought this engine many years ago (2014) for another project. Now it's going into the Wagoneer if someone can resolve the problem.
It's a 130hp P pump, stock, came out of a FrieghtLiner MT35. Replaced the injectors for a no load mid speed miss, that did not
resolve the problem. Timing is stock. I did put in the 3200 GSK.
It starts easy. After about 1/3 throttle it starts to miss and blow white smoke and flames out the exhaust.
Compression was right around 400 psi for all cylinders.
Replaced the IP overflow valve, just in case.
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If you're talking about the gasket on the front of the gear housing Cummins doesn't even recommend using that. Rebuilds get RTV between the front cover and housing. Of course you do have to replace the front crank seal anytime you remove that front cover. Otherwise it is guaranteed to leak. Just remember that the crank has to be totally clean with no oil on it when replacing that seal. No reason for them to have clamped the rods in a vice that tight. Nothing on the pistons and rods is overly tight. Those rods are super strong. No worries on those shinny spots.
I was talking about the Gear Housing Gasket, goes between the gear housing and the block, A real pain to get to.
Yes, that gasket is a bit of a pain. About have to disassemble the whole front of the engine to put that gasket in. That gasket generally doesn't leak very often but should be replaced on a full overhaul.
Got the cylinder head back from the machinist, It's a write off. All of the valve seats had multiple cracks and there were several cracks from valve seats to the injector ports. A new complete cylinder head with valve train assembly installed is on the way.
Will that mean new injectors too? Any new head should be 7mm injector holes unless you're picking up a used one.
Will that mean new injectors too? Any new head should be 7mm injector holes unless you're picking up a used one.
The injectors are new, 7mm.
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Sounds like progress! Good job even though there are a lot of hard knocks. It’s hard to tell what would be more costly, going through one like you’re doing or not going through one. You will know what you have. At your juncture, I had wrist pin bushings redone at a properly tooled machine shop after machine shop #1 ‘borrowed a tool from John Deere’ (tapered bushings) to install, then honed by hand I believe. Maybe don’t mess with wrist pin bushings if yours feel right and measure to spec. A good machine shop will install then ream bore all 4 OS inside diameter bushings to spec and equally center to center of the rod.
Yes, some progress! The wrist pins measured up to spec, so the only other item that is untested is the, transmission. I have had it running with the engine for maybe a total of 2 hrs on the test bed. The insides look clean, the pan was clean. Installed a shift kit and a new torque converter.
At last it runs Great! All it took was a set of new chrome rings, a set of standard bearings for the crank shaft and rods. A quick pass with a flex hone and a new cylinder head.
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Glad to hear positive progress.
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