Need 2QM15 expertise - SEIZED

[higgs]

This is a big time long shot. Make sure you are not in gear by going below and checking the shifter AT the tranny - not at the wheel. If something wrapped your prop just as you shut down it could have damaged linkage to the tranny and left you in gear. With a fouled prop and an engine in gear one would easily suspect a seized engine. I know this is pretty far fetched, but it won't be that hard to eliminate this possibility. Sometimes stuff like this happens - it is very rare but.......................

 

[garylinger]

I appreciate your suggestions about checking for prop fouling, stuck in gear, etc. but when I came into the slip the last time I let the engine "cool down" in neutral (at idle) for several minutes after revving it (as recommended in the owner's manual). If it had been stuck in gear or had fouled prop I would have know it then. I am still guessing that a small amount of water has leaked past the head gasket and rusted the piston ring to the cylinder wall. The leaky head gasket could explain the hard starting (loss of some compression). Does that make sense to any of you with more experience?

 

[Ross]

When you tried to turn the crankshaft with a wrench how long was the handle? It may take a breaker bar and socket to give enough torque. Just don't twist the bolt off. If you have a bit of rust in a cylinder and can't break it loose from the outside then you are bound to have to go inside. If you can get the injectors out and squirt some Marvel Mystery oil in the cylinders and continue to try turning the crank you may have success.

 

[cbsailor]

Check out the "clunk"

A friend had a similar problem with a 4 cyl yanmar in a H40. The starter would not turn the engine over. It would however make a "clunk" sound. Attempting to turn the engine over by hand only resulted in the slightest movement of the crankshaft in either direction. He and another friend's diagnosis was a "rod or dropped valve". Considering the age of the engine (1986) he decided to purchased a new engine and had it shipped. He struck a deal with a local person to help him get the old engine ashore and the new engine to the boat (we were living on mooring balls in FL at the time). The deal included selling the old engine to the guy for $500.

While waiting for the new engine to arrive he began removing the old transmission to make engine removal easier. While doing this, he found part of the drive disk had disintegrated and jammed between the flywheel/drive disk and the bell housing. With the transmission/bell housing removed the engine turned freely.

The new engine cost him a bundle but he is very happy with it, especially the additional horsepower. The guy who bought the old engine was estatic with his $500 deal.

FWIW,
Good luck with you repairs.