Having overheating issues with an engine and want to run it tomorrow wiithout the thermostat ionstalled. The manual says that could cause overheating. I don't see how thats possible. The engine is a small block, mild horsepower with a stock raw water cooled system, including the circulation pump.

Anybody know why it would overheat without the thermostat?

Need answers quick...going boating in the morning.

Thanks

traditional thinking is that in a CLOSED system, the water would move too quickly thru the motor and not get a chance to heat soak. it is very unlikely it will do that in an open system because, even tho the water is STILL moving too fast and only taking away a fraction of the heat it should, the water that replaces it is back to " base line" cold so the difference in temps will simply cause the equilibrium to be lower. i think , if the tsat really is your problem, taking it out will make it run cold. if the motor is injected it will also run rich and stop in a matter of a few minutes if you run it w/out the thermostat.

The old Gray marine stuff would over heat in a big hurry without a t stat. Mainly due to water flow characteristics..

The SBC & BBC stuff usually is fine without a tstat, unless it is an efi set up then it may run rich.

However, Most jet boat engines dont run one at all.. Also there are many blown applications that dont run one as well.. Jamie / Lakeside

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