The previous owner of our '84 C-30 removed the thermostat from the Universal M18, after it's failure caused him to overheat the engine. Not being a diesel mechanic, my question to you is whether or not this is advisable. As it now stands I can't get the engine to warm up at or just above idle in neutral. But, we sail on Lake Travis in Texas, and in the summer the surface temp of the lake will reach 80 deg. So, I suspect that it will warm right up in summer water... I'm tentatively planning on replacing it, as I want to be able to heat water using the engine even during our "winter" (condolences to all who are frozen in right now). Any thoughts? Does the engine _need_ to run at temp?