Cooling temp fluctuates
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From: 3rd Rock
Originally Posted by vhswrestler2005
after i replaced my thermostat my temp started fluctuating(overheat/cooldown while driving) i think it's my thermostat sticking, i also replaced my radiator at the same time
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From: Billings Montana
Originally Posted by vhswrestler2005
after i replaced my thermostat my temp started fluctuating(overheat/cooldown while driving) i think it's my thermostat sticking, i also replaced my radiator at the same time
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I keep hearing about air pockets, yet somehow over the last forty years we never had such a problem. Just put coolant and water into the radiator and GO!
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From: Niceville, FL.
In 50 years of vehicle ownership/maintenance I've never seen any problem I could attribute to an "air pocket". I suspect, as rough and irregular as the water passages in an engine are, turbulent flow would remove any air initially trapped within a matter of a few minutes after the thermostat opened.
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Fleet Owner
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From: Lake Tahoe, Nevada
It grounds through the temp sender. When changing the stat it may have been disturbed causing erratic readings. Check the connection, make sure it's sound.
A sticking thermostat will most often stick in one position so I doubt that's it.
A sticking thermostat will most often stick in one position so I doubt that's it.
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Joined: Sep 2005
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From: Illinois
I hope no one minds if I jump in here on the subject of air pockets...
When you drain your cooling system you get air in your engine's coolant passages. When you refill your system the air from the engine is trying to escape into the radiator through the thermostat. If your t-stat is good it will block the air from exiting. When the radiator is full there could still be air trapped behind the t-stat. It takes longer for the t-stat to open when it is not in direct contact with hot water so you could have a chance to overheat. Once the t-stat opens, the air bubble is gone and should operate normally after that. That's when you should let it cool down and top off your coolant.
I doubt an air pocket is the problem with vhswrestler2005's truck, though. It sounds more like a gauge problem or it could simply be low on coolant.
Originally Posted by srercrcr
I keep hearing about air pockets, yet somehow over the last forty years we never had such a problem. Just put coolant and water into the radiator and GO!
I doubt an air pocket is the problem with vhswrestler2005's truck, though. It sounds more like a gauge problem or it could simply be low on coolant.
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I agree with that.
Many newer cars though are having air pocket problems that don't disapear, apparantly because the radiators are a lower profile, the air seeks the highest point which is in the engine, instead of in our trucks where it's the filler neck.
Many newer cars though are having air pocket problems that don't disapear, apparantly because the radiators are a lower profile, the air seeks the highest point which is in the engine, instead of in our trucks where it's the filler neck.
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Joined: Jun 2004
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From: rural area
It could aslo be your fan clutch? I know mine whent bad, and would overhead wile in town... but be perfectly fine past 30mph.. So i put an electric fan in there... problem solved.
Sometimes you can even get a bad new theromsdat
Sometimes you can even get a bad new theromsdat