I am working with a friend trying to get his 300SD to start and idle smoothly. So far I have adjusted the valves, replaced the injectors and glow plugs and run a couple cans of diesel purge through it. The car sounds like it is missing on the #5 cylinder when it is first started and it smokes (I'll swear it looks white). I have started it cold and loosened the #5 injector line and there was no change - it continued to run badly. When I do this with the engine hot it does idle poorly like it should with an injector lined pulled. He just purchased the car off of ebay (160k miles thereabouts) and I have not seen any service/maintenance records. I have noticed too that someone has the idle cranked up to around 800-900 rpm. The car runs good on the freeway (don't they all
) but something is not right at idle and during cold starts. Another thing is that I suspect someone has installed a "drilled out" thermostat. The temp never gets above around 80 dC even when the engine is loaded. When I replaced the injectors there was quite a bit of liquid oil around the "barrel" of the injector. In addition, the glow plug holes were severly sooted - I had a hard time getting the reamer in there. The timing chain is stretched to the point where the crank is at 11 degrees past TDC when the cam is lined up. I will probably try to do a "drip" timing test on it over the next week or so too.
I am going to try to run a compression test this weekend. Could the fuel injection pump need calibrating? I am thinking that there may be a head gasket issue. I may try to keep if for a few days and observe some of the other signs that show head gasket problems.
thanks