Mercruiser bravo 3 overheats on step only

[Searaysundeck240]

Hi. I have. 2006 sea ray sundeck 240. Will over heat only when boat is near plane around 2600 rpm
go back to 1500 and will go back to 160 degrees
installed new raw water pump. Changed t stat and temp sender

 

[tpenfield]

:welcome: to iBoats . . .

OK, so we know that the sea water pump, the thermostat and the temperature sender are not the problem. :thumb:

What happens when you go beyond 2600 RPM? More overheat?

Tell us what Mercruiser you have (model and serial #) . . .

Closed Cooling? or raw water cooled?

Did this problem come on suddenly or gradually?

If raw water cooled, disconnect the hose at the 'exit' side of the sea water pump and then backflush the inlet hose that leads from the sea water pump up to the thermostat housing. This you can do by disconnecting the inlet hose at the t-stat housing.

If all else fails, pull the outdrive and look to see if you have any marine life clogging the inlet fitting at the bell housing (been there done that )