Overheat Alarm

[GraemeTuplin]

I have just purchased a second hand boat that has a Yamaha 130 Saltwater series 2stroke outboard On my first outing outboard was going well until I was running at 28 kmots when all of a sudden power left throttle and alarm started and continued for 10 minutes. The motor continued to run at 4 knots which allowed us to get back to shore. Has anyone had a similar problem and if so how did you fix

cheers Graeme

[boats.net]

Check oil level in engine and boat oil tank, check to see if overheating.

[GraemeTuplin]

I have rang motor mechanic that has said build up of salt on cylinders can cause the problem. He wants to remove the head and have cylinders re-bored. Does this sound right

[seahorse5]

I have rang motor mechanic that has said build up of salt on cylinders can cause the problem. He wants to remove the head and have cylinders re-bored. Does this sound right

Salt buildup is a known problem on that series engine but the basic troubleshooting procedures such as waterpump, thermostat, and poppet valve servicing have to be done first if it is an overheating problem.

First the alarm problem has to be determined, overheat or no oil?

If no oil, do a search on this site for the hundreds of same questions about the oil system and how to troubleshoot.