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1961 Johnson QD-21 Thermostat Installation

C

c-horse

New member
Hi,

I replaced the thermostat in my old QD-21 1961 Johnson 10 HP engine, and I want to verify if I installed the O-Ring correctly because the old one was destroyed and I couldn't compare with that. I have attached this pic and labeled the top of the thermostat, and also what I "think" is the top of the o-ring. I want to be sure I didn't put it in upside-down because I'm still having cooling issues.

Can anyone confirm if my "top" label is right on the o-ring?thermo2.JPG
 
Don't feel bad---the guy that made the parts drawings didn't know how it goes either. The seal goes with the skirt pointing downward, into the cavity. Flange on the thermostat goes in the thin groove at top of the seal
 

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fdrgator said:
Don't feel bad---the guy that made the parts drawings didn't know how it goes either. The seal goes with the skirt pointing downward, into the cavity. Flange on the thermostat goes in the thin groove at top of the seal
Click to expand...



Dang...I had a 50/50 shot, and I blew it!

Thanks for the input. I'll try flipping it and see if that helps.
 
kimcrwbr1 said:
Start the motor in a barrel of water withe the thermostat removed and see if water shoots out the hole.
Click to expand...



Yeah, in fact we tried that earlier just today. With the thermostat housing empty, there was no water going into the thermostat housing, but there were some puffs of air felt coming out of the thermostat inlet side. I think we're going to try replacing the impeller next but the puffs of air threw us off. If the impeller wasn't working, where would the puffs of air be coming from?
 
??----Cooling water dumps into the exhaust.------If there is no water you will get exhaust coming out the uncovered thermostat area.-----You have not replaced the impeller yet ?
 
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