md6a thermostat

santana30RI · #1 (**permalink**) 12-13-2011

I have a Md6a Volvo motor i just did work on and found there was no thermostat. I go the boat in July and it has been in the water running with no problem how bad is this?

Thanks

Capt Len · #2 (**permalink**) 12-14-2011

Assuming it is fresh water cooled ,no biggie. the engine takes a long time to come to temp if ever. Engine runs better and certainly more efficiently with the proper thermostat to control this. Your engine temp gauge becomes useful and looking at it can tell a lot about conditions below.

santana30RI · #3 (**permalink**) 12-14-2011

It it raw water cooled

shogan50 · #4 (**permalink**) 12-14-2011

it will be more efficient with the thermostat. Volvo gets $75 for the one with their name on it. You can find equivalent at NAPA for a fraction. If in salt water, use 140 degree. If fresh water, use 160 or 180.

tdw · #5 (**permalink**) 12-14-2011

Our raw water cooled Bukh never got up to anything like a good operating temperature, nor did Volvo MD6b in boat before that. Seems to me that unless they have a plastic bag sucked up into the system raw water donks just don't get hot.

ebs001 · #6 (**permalink**) 12-15-2011

Running a diesel below proper operating temperature produces condensation in the fuel. A diesel should always be run right at the rated operating temperature. The thermostat is there to maintain that temperature.