(Un)seizing a '92 12 valve
 

Hello all. I have checked for this info on the web but have not been able to locate some specifics which I hope to have answered here via your expertise.

I recently bought a '93 5.9 cummins 12 valve. It is the engine only and complete minus the turbo and accessories. I was told this engine was very recently rebuilt. Anyway the guy who sold it to me suggested it may be seized from having sat so long. So far all I did was play with the fly wheel a bit to verify this and it did NOT seem to want to turn at all.

I realize these are high compression engines and hard to hand turn but I didn't want to pry too hard or damage anything so I am kind of operating on the idea this engine is seized. I have not hooked up a starter to it and tried cranking it yet though.

From what I understand, i need to pull the injectors and put diesel fuel or ATF down into the cylinders in hopes this seeps in and frees the psitons. I checked the oil in the pan which looks in good condition so I don't believe water inside is a factor.

My question is; after a week or so of letting diesel sit in the pistons do I then hook the starter up and see if it will crank? Or what is the safest way to verfiy the engine is not seized after this procedure?.

Also feel free to throw any additional advice you feel relevant. I'm super new to the cummins world.

Thanks!!

I've always poured Marvel Mystery Oil down in the cylinders of old tractors that were froze up. After a couple of weeks, they always broke free, and never seem to have a problem.