AQ 125A is reaching 260 degrees...why would this be happening?

[sundance232]

In reference to an old topic linked next, http://forums.iboats.com/forum/engin...a-over-heating

I Have a volvo penta AQ125 with a 270 out drive ; I've replaced the thermostat ,cap,& impeller and it still runs at 260 degrees; What could be wrong?

 

[Nhpatriot]

Is the raw water outlet of the heat exchanger cold?
This is the Cooper pipe coming out the top starboard side of the raw water strainer.

 

[captmello]

I Have a volvo penta AQ125 with a 270 out drive ; I've replaced the thermostat ,cap,& impeller and it still runs at 260 degrease ; What could be wrong?

you should start your own thread. this is a thread from 2+ year ago.
I would look at the intake side of the cooling system. The elbow just under the ujoint bellows and the gasket below that elbow are common trouble areas.

 

[jerryjerry05]

Is this while running or at an idle??????
The first place I'd look is the manifold.The buildup could be blocking the water from exiting the small holes in the end.
The heat exchanger could be clogged too.Try back flushing the system?
The pump housing, it could be wore. The cam can wear out.The cover any grooves or cuts. the inside the same?