Hi all!

Finally getting around to pulling the OM617 out of the rustmonster '85 300D. The car had been run on WVO, apparently, and when I disconnected the line to the (added, Fram) pre-prefilter, out came yummy-smelling syrup.

I definitely don't want to damage this engine, as it ran very well when purchased, and is intended to be the "new" motor in my pickup truck.

I did some searching and reading. The best summary thread I found was Saving WVO orphan! Input? which gives a number of options for cleaning the terminal fuel delivery system.

I note that biodiesel seems to be a good system solvent/cleaner, something that won't damage components, and will dissolve WVO deposits. I also like the idea of biodiesel not smelling the place up as badly as diesel, and not being and harsh/dangerous/explosive as a lot of the alternatives.

My goal is to disturb the engine as little as possible, as it's not (yet) a leaker.

My thoughts so far:
Remove everything up to the lines to/from the lift pump.
Manually flush from a fresh batch of biodiesel until clean fuel comes out of the relief valve.
Detach the hard lines at the injectors and repeat the flushing process until those all flow clean also.
Remove and rebuild the lift pump.
Reinstall, and see if the motor will start on biodiesel.

So, what am I getting wrong here?

Also, how many gallons should my "coolant system" be for test running a cradle-mounted engine? I'll be using water and Redline additive.

Anything else I need to know up front?