Posted by Joe Lorenzino on Sunday, February 01, 2004 at 6:33PM :
In Reply to: Dumb diesel question for the experts posted by Stan on Sunday, February 01, 2004 at 4:20PM :
I think the "bad" engines Stan is referring to were the early gm conversions of an Oldsmobile gas engine into a passenger car/ light truck diesel back in the 80's. The engineers started with an existing gasoline engine, and changed enough components (heads, crank, pistons, injector pump instead of a distributor, etc.) to turn it into an easily produced diesel that would be a near bolt-in to the different corporate vehicle platforms of the time. They did not work very well compared to an engine that was designed to be an industrial diesel from the beginning. Improvements were made in the next generation, but they never made it up to the level of a Cummins. The overall durability was not great, and they had a nasty habit of spitting the crank and rods out the bottom if you tried to drive them cold. (the injector timing was advanced for better starting until the engine reached a certain temp.) They also had a lot of crackage problems especially around the bottom of the cylinders near the main bearing bolts. The engine rebuilding shop next door still has a "display piece" comprised of the center 3 mains and 2 crank throws of a 3 piece crankshaft with all 4 rods and all 3 mains still attached and torqued down. (broke all 3 of them out of the block at the base of the cylinders/ main bolt holes) That is how they found it in the oil pan of the engine. A good, rebuildable block for one of these used to be a valuable piece due to their scarcity. Many farmers in this area bought them because it allowed them to run on cheap (nontaxed)farm fuel, and they were one of the few factory diesels available in la light truck. I haven't seen one in a long time, but there are probably lots of them still out there behind the barn for real cheap, which is still probably more than they are worth. When they broke, lot of them were replaced with an Olds engine which was a lot cheaper, and pretty much a bolt in swap. J.V.L.
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