Engine overheating

[Bubbie]

I have a 1992 Yamaha 30 hp 2cylinder outboard. My buzzer is going off at the throttle. The engine is not oil injected so it leads me to believe that it is overheating. However, I have water coming out of the tattle tail at the same rate that is has always come out. The engine is running like it usually did. I am wondering if there is something else I sould think about if the impellor is ok. I am not sure of what else could cause the engine to overheat if I have plenty of water running through the engine. Any help would be greatly appreciated and I am also curious if there is anyone else who has seen this problem. One more point, I have been running everyday for the last two weeks and then all of a sudden it started doing this last sunday. <br /><br />Thanks<br /><br />------------------<br />Bubbie

 

[12Footer]

Re: Engine overheating

Someone else posted a similar problem here some time ago. I recall someone sujested it was the temp sensor had gone bad. Can you touch the block by the head without getting burnt? Has the paint discolored or blistered around the block?<br />Both are signs of overheating,the latter being serious. The tell-tale just lets you know the impeller is pumping. You may have an internal blockage in the cooling jacket. but if you can touch the side of the block,and not get "blistered" yourself, then I would suspect the temp sender/sensor.<br /><br /><br />------------------<br />I'm no expert, but I DID sleep at a Holiday Inn last night!

 

[Bubbie]

Re: Engine overheating

I have pulled the thermostat and I am going to replace that this evening when I get home. I am not familier with the Temp Sensor/Sender. Where is this located and how difficult is it to change out myself. When I pulled off the thermostat there were some kind of particles in there. It almost looked like sand. <br /><br />Thanks<br /><br />------------------<br />Bubbie

 

[Bubbie]

Re: Engine overheating

One more thing, the engine didn't feel any hotter to the touch than it usually did before I got this problem.

 

[12Footer]

Re: Engine overheating

I don't know where the sender is on your engine, but it will be somewhere on the block of the power head, PROBABLY close to the t-stat hojusing. It will have a wire (some have a pair of wires) comming out of it.<br />But one thing further,If you had sand behind the t-stat, I think you found your problem.<br />Before installing the new t-stat, flush the motor reall good, to prevent anything left in the water jacket from fouling the t-stat again. Then replace it. It wont harm the engine to run it enough to flush out the engine's cooling curcuit, but do replace it afterwards.<br /><br /><br />------------------<br />I'm no expert, but I DID sleep at a Holiday Inn last night!

 

[Bubbie]

Re: Engine overheating

Thank you very much. I got the new T-stat and I will take you advice and flush out the engine before reinstalling the new one. Thanks again for all you help.<br /><br />------------------<br />Bubbie