engine overheat

[Barry]

I seem to have lost a lot of power. When motoring with my H30 YSE 12, I could only get 3 kts (measured by gps).. the engine would not rev up well. When I came into the dock, the kill lever was too hot to touch. I,' thinking a fouled prop may have caused the engine to overwork not sure didn't check at the time. I checked the stern and water was coming out the exhaust as usual. The engine always did seem to run a bit hot, but this was unusually hot!! No temp gauges on the boat. any ideas as to why it would not run up to speed and get so hotany ideas greatly appreciatedBarry

 

[Tim Schaaf]

Exhaust elbow

A major cause for overheating comes from a corroded exhaust elbow. This happens, inevitably, with age. The salt water meets the exhaust, and formes a very corrosive mix. The passage for the water becomes narrowed if not blocked and so less water moves through. The fact that the engine has always run a little hot may substantiate this. Additionally, if the corrosion blocks the exhaust gasses in any way, back pressure can prevent the engine from reaching the correct RPM's. But, this is neither hard to check nor replace, thank goodness.

 

[Andy Howard]

engine would not rev up well

I had this happen a few years ago, check the prop first for barnacles etc.

 

[Debra Blatnik]

Raw water or fresh water cooled?

Do you have a closed cooling system? If so, has it been checked/serviced? The raw water side may be working fine (spitting water out the exhaust), and still the closed system may need attention.