1980 300D sat for a year, won't start

[CommieGIR]

Hello All!

While I'm new to your forums, this isn't my first diesel, although I'm used to Volkswagen TDIs and IDIs. Bought my first Mercedes 2 weeks ago, an abused but excellent condition 300D Station Wagon with the OM617 3 litre engine.

Well I got it home on a trailer, but cannot get it to fire. It had biodiesel run through it, then he left it sitting for a year, and now that I have it, it will not start, cranks strong, and occasionally I'll hear it cough but it will not start.

I've shot the glow plugs, though I found shooting them odd (was seeing 12 volts even with the key off, but if I turned the key to start, the voltage at the fuse to the glow plugs dropped to zero), changed the oil with fresh synthetic 5w40 diesel oil, new oil filter, new fuel filters, and new air filter.

Still just cranks, never starts, I've bled the fuel system, and am actually running it off a jug of diesel because of the old veggie oil in the tank.

I'm out of ideas, anybody got some help for me?

Engine has 226k miles on it.