I've replaced the engine in an '81 240d with one purchased on craigslist from a guy who allegedly bought it from a wrecking yard for a project he subsequently abandoned. The old engine died from oil starvation after spinning a rod bearing. I've no reason to suspect that the new engine is bad, but natrually I'm aware of the risk that it is.
All is reconnected, fluids topped, etc. I prime the pump with the plunger thingie, and start cranking.
After many minutes of cranking, and a couple of new charges on the battery, the engine began to sputter. I figured that one more charge on the battery would do it. But after that fresh charge, when I turned the key, I got only a clunk. The solenoid does its thing, the starter tries, but the engine doesn't turn.
I concluded at first that I'd overtaxed the starter, so I took it out, gave it a good cleaning and greasing, and put it back in. Still only a clunk. I swapped the starter and cables with a known good set from another car. Still only a clunk. The cables get warm, so current if flowing. Ok, it's not the starter.
I took out the injectors and glow plugs. As you would expect, it cranked freely now. I replaced them all with known good units. Once again, it cranked freely, but with no signs of life. And after a while, back to the clunk. I'm back to the same point again.
Somehow, the engine seems to get into a state where it won't turn over with the torque the starter has available. Am I filling one combustion chamber with fuel and causing a hydraulic lock or something?
I'm new to diesels. What am I missing here?
Thanks in advance for any wisdom you might offer. I'm running out of ideas.
-Paul