nautique 200 overheating

[lilet]

hello,
I have a Nautique 200 2010 model PCM 5.7 with 1000 hours.
will towing at about 2.500-3500 rpm the temperature gauge goes from 175 to 200 degrees
and in about 20 seconds drops again to 175. engine check light flashing some times. It is not
happening every time cause on the way to the port for example was cruising at 3000
for 5 minutes and temperature was at 175 all the time.
do you have any suggestions?
I've changed the impeller, check tha sea strainer and water intake.

[AirTool]

Your thermostat in the block is sticking and/or slow to open.

By the way, you now have the record for hours per year on a 200.

[migs]

1000 hours on a 2010!!! thats what im talking about

[lilet]

yes I know but it's for professional use! 1040 hours today!
by the way I haven't change thermostat and temperature haven't rise tha last 40 hours.
engineer told me that might be broken circulation pumb.

[AirTool]

yes I know but it's for professional use! 1040 hours today!
by the way I haven't change thermostat and temperature haven't rise tha last 40 hours.
engineer told me that might be broken circulation pumb.

As the weather gets hotter your stat is opening more to start...probably past its "sticking point".

[lilet]

that's sounds right. still no problem with temperature again.
thank you