YAMAHA 150 2 STROKE OVERHEATING

[patrick16]

I have a 1996 Yamaha 150 Saltwater Series 2 stroke. The engine started overheating early in the summer. It has had the following done: t-stats tested, 2 new head gaskets, new impeller and "pump kit". After these repairs the motor seemed fine for a few times out and then overheated again this past weekend. We never got out of the no wake area and were running slow for about 10 minutes. The tell tale has always worked. I was very careful to shut the engine down each time this happened, I don't think the engine was damaged. Any help is greatly appreciated.

 

[bigbrownbuku]

Re: YAMAHA 150 2 STROKE OVERHEATING

was the pressure relief ever serviced while the other repairs were done? its as an important part of the system as a thermostat. has the exhaust cover gasket ever been replaced or the powerhead ever been removed?

 

[patrick16]

Re: YAMAHA 150 2 STROKE OVERHEATING

Thanks for the info. I know I need to get a service manual. In the mean time can you tell me where the pressure relief valve is located?<br /><br />Thanks again, Patrick

 

[rodbolt]

Re: YAMAHA 150 2 STROKE OVERHEATING

I take it thats a negatory on the pressure control valve and grommet service?<br /> dont make us dance. some of this dance everyday trying to get the whole story. so its easier to state just fact. if the valve leaks at low speeds it causes a low water condition at the top of the block. usually happens below 1000 RPM.<br /> the valve looks like a small t-stat housing on the lower stbd side of the exhaust plate. dont drop the grommet into the cavity. if you do repost under a seperate post and wait before attemting to remove the cover.

 

[patrick16]

Re: YAMAHA 150 2 STROKE OVERHEATING

Thanks to both of you for your help. rodbolt, I'll try to be more specific and complete with my questions/answers next time, and I am definately getting the service manual.<br /><br />Thanks again, patrick

 

[rodbolt]

Re: YAMAHA 150 2 STROKE OVERHEATING

no worries, its all easy.