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Old 10-03-2011, 10:39 PM   #1
85sierraclassic
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temperature gauge fluctuates?

hey all,
so today i finally decided to replace my heater core and put a thermostat back in. i got everything done and filled it all back up with a 50/50 mix and let it run till the thermostat opened and added coolent as needed and what not. the temperature seemed right, bout 195 or so it opened and dropped back down to 160 or so then came up some and leveled out bout 180 or so but after driving a little it seems like it comes up to about 190/195 then drops to about 160/165 and just kinda every 20/30 seconds it goes back and forth. i had the heater on high the whole time threw out all of this but dont see why its flucuates so much?
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Old 10-04-2011, 06:10 AM   #2
donut
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Re: temperature gauge fluctuates?

What temp is your thermostat? Mine used to fluctuate between open/close, trying to maintain temp. Especially noticeable when it's really cold.
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Old 10-04-2011, 08:29 AM   #3
old Rusty C10
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Re: temperature gauge fluctuates?

it could be a defective thermostat.. ive seen that happen more than once
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Old 10-04-2011, 08:49 AM   #4
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Re: temperature gauge fluctuates?

Quote:
Originally Posted by old Rusty C10 View Post
it could be a defective thermostat.. ive seen that happen more than once
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Old 10-04-2011, 10:11 AM   #5
motornut
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Re: temperature gauge fluctuates?

we lose heat as the air goes threw the rad
if the air is cooler fall/winter you will lose even more heat from the rad
i cover mine after the temp drops to 0 or 32 for you
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Old 10-04-2011, 11:15 AM   #6
85sierraclassic
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Re: temperature gauge fluctuates?

oh well its a 195 thermostat and it was about oh i dont know 55-65 outside maybe a little hotter colder give or take lol, it does seam like its just opening and closeing so maybe it is just a bad thermostat idk thanks for your opinions.
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