Picked up an '04 D2 for a few hundred dollars earlier this year. It has a seized engine, but otherwise in decent shape.

Tearing it down, it's quite obvious that something was done to the top end as the heads are clean as a whistle, as are the plugs. Looks like a head gasket job that only lasted about one mile before the engine seized.

I've gotten as far as tearing everything off the top except the heads. I have also removed the front cover and oil pan and am attempting to dismantle the engine interior piece by piece until I can get it to turn over so I can unbolt the flex plate.

Thing is, so far the guts look fine with nothing jumping out as obvious to why it seized.

What should I be looking for?

 

Things that can seize your motor include failed rod bearings, failed main crankshaft bearings, piston ring failure, broken block/crankshaft/camshaft, or even fatal piston slap failure in the cylinder.

It's more often than not fatal to the motor at every level (some exceptions).

There's only a small chance (if that!) of being able to reuse the block or major components if you truly can't manually turn the engine after deliberately overfilling with trash oil, spark plugs removed and in Neutral.

 

It might be possible to break it loose. I bought a parts truck with a "seized engine" due to overheating. Starter couldn't turn it over, I couldn't turn it with a breaker bar etc. I put a bottle of Marvel Mystery Oil in there and let it sit for a day. Turned it over with a big breaker bar the next day. It ran, but not good. Engine ended up having a bad slipped liner and the camshaft was gone , but the heads were good and I reused them.

 

Where is "in there?"

 

Was there oil in the sump?

I just wondered whether the previous in a hurry forgot to fill the engine with oil. The only other possibility I can think of would be a failed oil pump or an overheat.

If you can get another cheapish engine, maybe a 4.0L, drop that into the truck and rebuild this engine carefully at leisure looking into all the possible failures.

Engines only seize for a reason, more often than not lack of oil circulation or an overheat.

 

Oops, I just noticed you took off the oil pan and front cover. I put the Marvel oil in the with the engine oil with the engine together. Then after a day, I drained it all out and took the pan off. Then I used the breaker bar.

Probably not worth it for you to put the oil pan back on to put in the mystery oil.

If you can't see anything hitting inside the engine looking up from the oil pan or down from the top, I'd probably try the breaker bar on the crank pulley. Or take the heads off first. It makes getting to those torque converter bolts a lot easier when you go to separate the engine later.

 

Difficult to believe that would make a difference. You may have eaten Wheaties the next morning.

Pouring in cylinders a slight possibility of helping if it's been sitting for sometime.
......

 

Must of been that and the Popeye's Spinach! I couldn't believe it either. Was about to toss in the towel and call the whole thing a boat anchor. Who knows? I liked to think it helped. It was the advice of a tractor mechanic friend.

 

Well, after sitting for almost a month with the oil pan off and the spark plugs removed, it now freely turns over with a wrench...

No idea why.

Engine is finally coming out this weekend.

 

Did you try to turn the motor over after removing the plugs befor it sat? I wonder if someone had the wrong plugs in it and they were preventing it from cranking? Just a thought. D*