won't keep running????
 

need help! i just installed a re-built cylinder head on my 300d non=turbo.
valves a re adjusted(double checked). chain timing is aligned(double checked)
ip checked, drips at 24 deg, loosened injector line fuel comes out. checked compression all are 340 psi +/- 3%.
it's hard starting, when it starts to run, it only goes for about 10-15 seconds and dies, very hard to re-start and when it starts only goes for a few seconds. any advice would be appreciated...thanx...john
it's a 1981 300d :confused:

Pretty sure not the cause or you have checked it already. Crankcase breather system really totaliy open? The only reason i dare mention it is the run time after starting might concievably be about the same if it was obstructed. More likely fuel supply related. But if all you basically did was remove and replace head and engine was running without this problem before I would check everything I did very carefully first. One of my 240s runs about ten seconds with the blowby pipe obstructed before quitting when engine cold. If i obstructed this system before trying to start I know it would further reduce run time as well. Your engine could also be building up a little base pressure when cranking that is partially shutting off fuel cut off device making starts very subjective.. My second thought since your compression is pretty good is that you are starting with marginal glow system and engine will not sustain itself and dies out as not enough fuel or heat for initial run conditions. But at least there are far superior minds on this site than mine and they will post soon enough. Just some thoughts and hope not to add confusion. :)

Air leak in fuel system.
Do you have old "screw down" primer pump?
If yes, does it leak diesel when you prime the IP?
If Yes, replace it - if it leaks diesel out, it will leak air in.
If no to any of above, try operating from a small fuel can with the fuel line and return line runnng from the can. Prime the fuel system and start the engine.
Does it run normally?
No? You may have air in injector lines, loosen injector line nut at injector and crank engine to release any air. When fuel pools at injecotr nut, tighten and try starting again.
Still no running?
Check for vacuum applied to shutdown diaphragm. This may cause under fuelling at idle setting.
Let us know how you went.
Tony
The Wizard of Oz

Sounds fuel related too me. I have a bucket rigged up to hang above the car with fuel to feed the engine which I would break out at this point.

You can tow start those cars also. I had a 240D that just wouldnt start when I'd work on the fuel system. After a couple of times of messing with it for half a day I would just tow start it and it would be fine. If thats a option for you it might save some futzing.