is it possible to repair a boat motor that is siezed?

the motor has been idle for sometime


the motor is a gasoline motor and has sat unused in a barn or building of sorts,, I don't know anything else

6 Answers

  • Anonymous
    1 decade ago
    Favorite Answer

    Is it just from sitting unused that it wont spin or turn over??? if so put Marvel Oil in piston thru sparkplug hole and give it some time to penatrate, then try to turn motor slowly!!should free up? if motor is damaged from an accident or blown up ? tear down rebuild, and good luck as a boat motor is expensive when it comes to repair parts!!

  • 1 decade ago

    Clearly it is an engine, but the terms are used that way in connection with boats. A motorboat has a motor, even though in engineering terms it is actually an engine. So it's okay to call it a motor. There are enough things to worry about in this world, without kicking each other over the "motor vs engine" thing.

    Aside from that, the other answers are essentially correct. If the motor/engine was operating well the last time it was run, it is probably just corroded, and it can be unstuck with penetrating oil as described in one of the answers. If it is an outboard thingamajig, lay the engine down so that the spark plug holes are uppermost, and inject penetrating oil through the spark plug holes. After a couple of days it should be possible to turn the motogen slowly with a wrench or a pry bar.

    If it is still tight, try removing the oil sump and using penetrating oil on the main and rod bearings. If it is an inboard, the spark plug holes will in most cases be facing up, but you will have to take the engotor out to get to the oil sump.

    If the engine seized because of a mechanical accident or overheating or running out of oil, it will have to be completely taken apart (mechanics say "torn down") and inspected. If the block is damaged, it is probably not worth fixing. Most other parts can be repaired or replaced.

    If it is an outboard motor (which is also an engine, but don't worry about it) it will probably be easier and cheaper to just get a new one. Go see the outboard motororengine shop and they will be happy to sell you one and let you call it either a motor or an engine.

    Good Luck and happy motoring!

  • jack w
    Lv 6
    1 decade ago

    Cost depends on why its seized. Usually an engine will not seize up from just sitting except for very long periods of time. Was it run hot or without the proper gas/oil mixture before being idled? Sometimes idle engine seize becaue a little moisture managed to get in the cylinders and rusted the rings to the sleeve. Remove the plugs, lay the engine so the plug holes are up and squirt alot of penetrating oil into each combustion chamber and let it set for 2-3 days. After waiting, try to turn the engine over with the plugs still removed. If it won't turn, you may have to remove the cover for direct access to the flywheel and crankshaft. Using a wrench on the crankshaft/flywheel nut and see if it will move a little. If it does, just rock it back and forth several times and put more oil in the combustion chambers. Let it set again, 2-3 days, then go through the procedure again. Hopefully, after this it will turn over with the starter or pull cord. If not, the upper end may have to be dis-assembled and freed up.

    If you have to pay for this to be done, it could be very expensive and easily exceed the value of an older engine.

    If you're going to do it yourself, and don't have one, go to the local library and see if they have or can get an overhaul manual for your engine. Good luck.

  • Anonymous
    1 decade ago

    Is it a motor or an engine?

    A motor by definition is electric, an engine is internal combustion.

    If it is an engine...

    It depends on why it seized.

    If it seized due to a broken crank or other mechanical problem, it would need to be inspected to see if any damage was done to the block. If not, replacing the bad parts should fix it.

    If it seized due to sitting with water in the cylinder, SOMETIMES you can get it loose with penetrating oil in the cylinder(s).

    If that is the case, it will usually need to be disassembled, cleaned and inspected.

    It might be fixed by cleaning & honing the cylinder(s) and piston(s).

    If it is a motor, take it to a repair shop.

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