Running hot

[cambam78]

So my 82 Sea Ray with a Merc cruiser out drive heated up on me on the lake. got so hot you could hear the water "sizzle" off the motor as the kids were getting out of the lake. Obviously the temp gauge or sending unit is not working. That being said, Any chance this is a thermostat, or am I looking at pulling the out drive apart and replacing the impeller?

As a side note, when I have been running it out of the water, hooked to the muffs, it has not been getting hot.

Thanks in advance!

 

[JimG]

Starving for cooling water as the RPM/load increases... common symptoms of a bad impeller. I hope you didn't damage the engine. There are a few gages you have to keep working... oil pressure and temperature!

 

[mwph]

There are a few gages you have to keep working... oil pressure and temperature!

Well said.
Isn't it also true that "pumping" water in with the garden hose can mask those same symptoms? I'm trying to figure out how water can land on the engine when people climb on the boat. But thats another subject.

 

[cambam78]

The water was leaking between the engine cover and the fiberglass at the back of the boat. (the engine cover opens forward). Not a lot of water,but as the kids would get out of the lake and climb across it,a few drops would get through. It seems to me like hooking it to a hose may mask the impeller issue because you are "forcing" water through the engine. I was hoping for better news, but I guess we are taking apart the out drive. I will let you know what I find.

 

[kbsunlovers]

While you have the drive off, check the water hose running from the gimbal to transom for kinks. Check all the water hoses, in fact.

 

[chandalen]

Impeller is most likely because you said everything is fine on muffs.
The garden hose is forcing water into the engine, where while running water needs to be sucked in by the impeller.