92 Yamaha 225 knocking noise

[242]

Help! I just purchased a 92 yamaha 225. The compression test was good reading 4 cylinders at 125 one at 127 and one at 123. When we put it in the water the other day we could here the slightest knocking noise coming from under the flywheel. My mechanic thought it could be the upper bearing on the crank and that this could be replaced without tearing the engine apart. He came back and told me today that if the bearing is bad it is most likely a sign of a bad crankshaft all together and the engine would have to be torn apart. I have a second opinion coming next Monday from a local marina that has certified Yamaha techs. Any ideas or comments would be appreciated.

 

[242]

Re: 92 Yamaha 225 knocking noise

bump

 

[rodbolt]

Re: 92 Yamaha 225 knocking noise

fresh or saltwater engine?
the upper mains just dont go bad. lowers do but rarely uppers unless water intrusion is a culprit.

 

[242]

Re: 92 Yamaha 225 knocking noise

Rodbolt,
Thanks for the reply. It has never seen the salt but will now be in the salt. What would you guess that noise to be. It sounds as if it is right under the flywheel.

 

[rodbolt]

Re: 92 Yamaha 225 knocking noise

beats me, but its not hard to remove the flywheel,check the stator and pulser screws. if ya wish from there, the upper bearing is not hard to remove.

 

[giantuna]

Re: 92 Yamaha 225 knocking noise

I got the same noise.
Is it a knock or a tick?
Heard that if it was the staor then it wouldn't run at all, don't know what to believe.
What are the pusar screws? Is that what mounts the flywheel?

 

[dusouth]

Re: 92 Yamaha 225 knocking noise

I had the same noise yesterday that just appeared. Well i found it realy quick when the rod come out the side of the engine. Thats probably if i had to guess the number 2 piston on your engine making the noise. it is the next bearing in line there. Hate to be the bearer of bad news but good luck.