1992 Yamaha C115 Outboard

[ort]

While running at speed there was a sudden grinding noise and the engine lost rpm and shut down. It would not start again, and the starter was having trouble turning the engine over. I have replaced the starter but the new starter is also having trouble turning the engine over. When the engine does spin fast enough and tries to fire, it sounds like it locks up tight and the starter is locked with it. I have also drained the lower unit and the oil looked fine except I did see one piece of shaving. Any ideas as to whether this is an electrical problem, an engine problem or a gear problem?

 

[Trent]

Re: 1992 Yamaha C115 Outboard

I love these engines!<br /><br />Remove the sparkplugs and see if she will spin over faster? <br /><br />The C115 is the commercial model and you have been mixing the oil at 50:1 ?<br /><br />If your still having problems...Drop the lower unit and see if it will turn over faster now. If not remove the heads and check for cylinder damage.

 

[ort]

Re: 1992 Yamaha C115 Outboard

Yes, I have been mixing the oil at 50:1. I have not had any other problems or concerns with performance. It was running great one minute and junk the next...

 

[ort]

Re: 1992 Yamaha C115 Outboard

I removed the plugs and it did seem to spin more freely. What does that mean??

 

[Trent]

Re: 1992 Yamaha C115 Outboard

It means you have some compression. Do a compression check on all cylinders. You may still have to drop the lower unit to see if their is a problem their. Do the compression check first. Compression should be 10 to 15 percent from each other.