yamaha 225hp with knocking noise. help!

[noeytina]

I need help with a 2000 yamaha 225 hp engine. When we put it in the water the other day I could here the slightest knocking noise coming from the lower part of the motor. At times it goes away and at other times it sounds very loud. Compression has been checked and compression is very good. If any idea of what it could be please let me know.

 

[Triton II]

Re: yamaha 225hp with knocking noise. help!

Hey Noeytina,

I can't help directly with your problem, but I can help others to help you.

Please post up your engine's model designation and preferably serial number in full and hours run, prop and type of usage. What boat is it fitted to? Does the noise only occur in neutral or only in gear or maybe in forward gear and in neutral, but not in reverse (or vice versa... you get the picture). The more info you give, the more easily the techies on here diagnose problems. Good luck,

TII

 

[jeffersondodson561]

Re: yamaha 225hp with knocking noise. help!

If this is a 4 stroke it maybe a fuel restriction and you maybe hearing the mechanical fuel pump, if it is a 2 stroke I would check rod endplay, this is better done by someone that knows how to check for it.