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Engine seized while sitting, any hope of saving it?


New Member
This may not be the correct subforum but i dont think itll matter for this one. Ive got a 79 fox with an 89(ish) 5.0 HO in it. The car ran when parked but sat for about 20 years with no spark plugs, which is very not good. Went to rotate the crank to reinstall pushrods and rockers and it moved maybe an eighth of a turn and then stopped. I already sprayed it down with PB blaster and ill probably keep at it for a few dats before I try to rotate it. Is there even any chance I can free it? And assuming I do, will the rings and bore be intact enough that i dont have to pull the heads or tear the old engine down? This engine was supposed to be just put back together and new fluids and hoses so i could drop it in my 93 for the time and im hopping i dont have to rip it apart.


Well-Known Member
You can try filling the bored with transmission fluid and letting it sit for a day or so. Go back and work the crankshaft around slowly, without forcing it too much. Once freed up, let it spin with the starter a few times (plugs out) too clear the bores. Like Derrick from Vice Grip Garage says "the engine bay will look like a scene from Murder-She-wrote" lol!

After getting in going, it may smoke a while and the rings may come around and free up.

It really doesn't take much to do what you describe. So it may just be a little rust in one or two cylinders. If you have access to a scope, it'll make the job easier. You can focus on the crusty cylinders.

You also might try spraying some fogging oil down the bores. That stuff is pretty slick and may get it moving without all the mess.


You can also try soaking the cylinders in Marvel Mystery Oil. That stuff works wonders. I'm glad to see the VGG video link - he does a great job walking through bringing that engine back around.