I always thought that marine engine
such as a Perkins
4236 (indirect cooled via a heat exchanger) ran cooler than the vehicle model.
My understanding was that the road version burned hotter to help with exhaust
gas flow but that the marine
versions burned cooler to prevent deposits building up in the exhaust
Now by burn I dont mean the temperature of the flame front or ignition point but the block temperature.
I am asking because an associate has a dilemma, he does not know what thermostat to put into the fresh water
circuit. I suggested that it would be cooler than than the vehicle one i.e. open earlier. I dont know the engine
type just that its a Yanmar
Am I right or wrong or does it depend?