I have a 1995 Ocean Pro 175 with a seized piston.Looks like it got water in one of the cylinders. What would be the best way to remove the piston. I have removed the heads and put the motor in gear and tried to turn it by hand. Can't get it to move.
Tilt the engine up, put it in neutral and put a couple of tablespoons of Marvel Mystery oil in each cly. Let it sit for a day or two. Take a socket wrench to the nut on the top of the crank and see it it will turn. It may free up.
or pull the plugs out and put some diesel fuel in the cyclinders and try and turn the fly wheel each day till it gets free. diesel fuels cheaper and works just as good
Be very gentle with the turning attempts. If you attempt to force it free you run the risk of breaking rings and ring lands. Just rock the flywheel back and forth within the limits of travel. Insert more diesel fuel and let it sit a couple days. Repeat the process as necessary. When free, it would be a good idea to remove the head to see what damage if any was done. Generally there is piston scuffing and cylinder bore damage.
The heads are off. # 5 is seized, it's at the top of the stroke so I can't see the cylinder wall. Will keep adding diesel each day. Thanks for the replys.