TOPIC: Thermostat question

1976 Johnson 85hp 85EL76D
Guessing that the thermostat has never been replaced. When I bought the motor PO said it needed a new impeller. When I took everything apart I see that there was a new unused impeller kit installed but the copper lines running to the head were not attached, one was, the other missed it's mate in the drop leg. I put everything back together and finally had a chance to run it today but still no water dumping out. I removed the thermostat and back flushed the entire motor, water was coming out of the impeller inlet so I know that the legs are connected and the water jacket(s) are not plugged. Question, will a stuck thermostat prevent water from coming out the dump holes?
I did order a new one.

A thermostat is just a heat actuated valve which releases water from the block, either into a lake or in the case of a car, back into the top of the radiator. When closed, the thermostat holds water in the block to allow it to heat to a desired operating temperature, governed by the thermostat temperature rating. If it's stuck closed, water will remain in the block which will soon overheat because water can't escape through the stuck thermostat. Running with no thermostat is possible but that's a last resort. I'd replace it immediately. Buy two so you have one for a spare. They're cheap.

Gotcha Jan. One is on order. 43 years with the same thermostat, wonder how long it was going bad. The original one was in there, the gaskets, bolts etc. had all the factory paint on 'em.

They were remarkabley reliable.

Got one coming in the mail, should be this week yet. Tuesday I ran the motor on muffs with the thermostat housing off just to make sure the pump was working properly. Got good flow from both banks and the water was coming out warm. On a side note, the position of that thermo on the bottom of the engine close to the lower cowl is one SOB.

This is how happy I am.
Thermostat came Friday afternoon, 10 minutes to put it in. Finally got to run the motor today.
Smoke is from a good dose of SeaFoam.

Going for a WOT run in the evening when the weekend warriors are all home.
Interior needs some improvement.