I Just started to check out my 2 Dueces I got from Govliquidation. On one, on start up, the oil pressure seems to be ok. Its also kind of hard to start and you have to press on the throttle to get it to start up. Anyhow, after it runs for a while and warms up, the oil pressure slowly starts to drop. Even stepping on the throttle does nothing to the oil pressure gauge when its warmed up. By then, the gauge is reading almost 0 psi. It seems to run well enough without excessive engine noise. No noises I would consider abnormal either. I'm hoping this is a gauge problem and not a worn motor.
Any one have an opinion on this?
You need to check this out. Don't run it blind. This exact same thing happened to me and it turned out to be my injector pump was "making oil" and thinning out my engine oil, thereby losing oil pressure. Check your oil level asap. If it's way up on the dipstick, suspect a diesel leak into your crankcase oil. Smell your oil, if you smell diesel this also confirms the "making oil" condition.
If you confirm a making oil condition, then look at the posts on "bypass fdc". This is the fuel density compensator. It leaks much more often than the injector pump. What I did was bypass the fdc, dump my contaminated oil, and see what happened. I was unlucky; the injector pump leaked like a sieve and had to be rebuilt. This was easily confirmed by seeing the oil rise on the dipstick after the fdc bypass. Check out the threads on reading dipstick level, also, it varies greatly checking a cold engine versus a hot one, and other variables.
Then again, having said all of this, it could very well be a sending unit or guage. I went the long way around the barn on this response, just be aware of what it could be. Again, I would emphasize not to run the engine without KNOWING what your oil pres. is.