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Engine Break-in Thermostat or No Thermostat?

EngineerDoug

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Folks,

The title pretty much says it all - what is the consensus on engine break-in? Thermostat or no thermostat? BTW we are talking about temperature climate, maybe 60 or 70 degree day. Thanks.
 
Thermostat. I use 180°. Warm it up in a pan of water on the stove with a known acurite thermometer to make sure it works as it should.
 
Watch for leaks and have a fire extinguisher and a hose ready just in case.
 
YES!Thermostat. Like others said, you want heat in the engine. RUFFCUT
 
Before you install the stat, fill the engine with coolant as much as possible through the stat neck in the water pump housing. I often let it burp several times over a few days until the block is chucked full and then I leave the level a tad lower than the stat and install the stat. This keeps 98% of the air locks out of the equation because the block is full and there's little to no room for air behind the stat. I have never had one air lock when doing it this way. It is very hard to get the stat to burp on a fresh motor when the block is empty and you are fighting all that air.
 
Make sure you install the rad cap !! Years ago we were breaking in the motor with no rad cap. When I shut it off it puked the entire contents all over a buddy who was standing at the front of the car. He was scalded BIG TIME !! The skin literally fell off his upper body.
 
Drill a small hole in the stat ( 1/8" ) to help bleed air it won't slow the warm up noticeably.
Mike
 
Folks,

The title pretty much says it all - what is the consensus on engine break-in? Thermostat or no thermostat? BTW we are talking about temperature climate, maybe 60 or 70 degree day. Thanks.
ALWAYS use a thermostat. No exceptions.
 
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