Thermostat is missing

[gayle23]

I recently acquired a 1980 9.8 hp mercury, serial no. 5711241. The motor had a fried power pack, which looked as if it had gotten so hot at times the wires were essentially fried, brittle and broken. I replaced the power pack. I then found the thermostat is missing. I have replaced the thermostat as well. Is there a relationship between these two? Did the lack of a thermostat cause the power pack to heat up, or maybe did the previous owner remove the thermostat because the motor was overheating for another reason? I am trying to ascertain if I should keep looking for a reason the power pack fried, and the thermostat is missing. Thanks.

 

[Barnacle_Bill]

Re: Thermostat is missing

It was probably overheating on him. Check the impeller.

 

[gayle23]

Re: Thermostat is missing

I replaced the impeller even though the one which came with the motor was in good shape. If this was an impeller problem it may have occurred and the impeller replaced before the previous owner sold the motor. I think I should run the engine in a tank to see if it pees. If it doesn't I probably have an obstruction some place.

 

[Laddies]

Re: Thermostat is missing

That's not a uncommon thing on 80s engine to have the wire cracking and falling apart. Also the thermoststs on the 7.5 and 9.8 did not work that well and many were just thrown away.

 

[gayle23]

Re: Thermostat is missing

Thanks, that is good to know. Maybe by replacing the power pack and the thermostat with more modern components, I have helped to resolve the problem. I will still be careful to look for proper water cooling capabilities. This is a nice engine as even though it is almost 30 yrs old it is in great shape and looks new. Kind of fun to work on.