Engine overheat alarms

[Ripster]

I have decided to fit an early warning engine overheat alarm that gives a very early warning if water flow stops or is restricted to the cooling system. Its a pair of KAMD300s. Has anyone else fitted one to these engines?

The kit is fairly straight forward to fit and works on a sensor placed on the exh/water inlet elbow that causes an alarm at 90+ degrees (the temp should be 40-50deg under normal running apparently) but the only thing I am not totally sure on is exactly where on the circumference of the elbow to place the sensors? The easiest place is just next to where the water inlet enters the main exh pipe (on the top of the elbow outward side) but should it be at the bottom where the water flow first hits the exhaust (perhaps the coolest point) or does it not make any difference as the water is immediately splashed all over the pipe anyway?

 

[pappaecho]

Clearly the sensor should be placed downstream of the mixing between exhaust and water, and probably the position is not critical. I check my water temperature from the outlets in the stern. Mine are about 50-55 degrees, just about the hottest that the hand can tolerate.
As your seem to run at similar normal temperatures, I wonder whether 90 degrees is a tad high, 80 being a btter warning of above average temperature

 

[Salty John]

On our Sentry alarm the sensor goes immediately after the mixing elbow.

It alarms at 165F (74C) which is below the temperature at which exhaust piping material melts and gives a good early warning of an excessive rise in exhaust temperature.