Radiator fans question.
Thread Starter
Safety Car
Joined: Jul 2010
Posts: 3,950
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From: Chandler AZ
Radiator fans question.
I'm not 100% sure, I'll check soon
Anyways I think my radiator fans are running, I don't have on A/C, coolant temp is 198-199, I have temperature **** turned to 90, however no blower or heat on.
I have heard this 2 times now pulling into garage, after 33 mile trip home, mostly freeway.
Got the car put back together the night before thanksgiving and have been driving it since almost daily.
Had water pump off to do A/C compressor, coolant level fine, would a air pocket make the fans run?
Again I need to leave engine running, pop hood and see if, at least passenger side fan (driver's side fan is hard to see from up top if I recall) is running, but after turning off car I heard a fan/fans wind down.
Anyways I think my radiator fans are running, I don't have on A/C, coolant temp is 198-199, I have temperature **** turned to 90, however no blower or heat on.
I have heard this 2 times now pulling into garage, after 33 mile trip home, mostly freeway.
Got the car put back together the night before thanksgiving and have been driving it since almost daily.
Had water pump off to do A/C compressor, coolant level fine, would a air pocket make the fans run?
Again I need to leave engine running, pop hood and see if, at least passenger side fan (driver's side fan is hard to see from up top if I recall) is running, but after turning off car I heard a fan/fans wind down.
Last edited by 1999corvettels1; Dec 1, 2018 at 11:50 PM.
Burning Brakes
Joined: Jan 2006
Posts: 788
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From: Olathe Kansas
No reason they should run at that temp.. Maybe you do have an air pocket in system.
Go thru the burping process again and make sure coolant is correct level. Otherwise you may have
a faulty coolant sensor or a thermostat (even if new) acting up
Go thru the burping process again and make sure coolant is correct level. Otherwise you may have
a faulty coolant sensor or a thermostat (even if new) acting up
Thread Starter
Safety Car
Joined: Jul 2010
Posts: 3,950
Likes: 386
From: Chandler AZ
I have had the car over 15 years and never noticed this before, in fact in summer fans didn't come on until I believe 226 then off at 219 without A/C on, and my A/C was not working.
I really didn't burp the coolant this time, I do have a Lisle spill free funnel that I used September 2017 when changing out the coolant.
Just have to suck out the extra coolant when done, I actually forgot all about this, and was under the gun to get the car wrapped up.
Will give update after I bleed with the Lisle device.
I really didn't burp the coolant this time, I do have a Lisle spill free funnel that I used September 2017 when changing out the coolant.
Just have to suck out the extra coolant when done, I actually forgot all about this, and was under the gun to get the car wrapped up.
Will give update after I bleed with the Lisle device.
Last edited by 1999corvettels1; Dec 2, 2018 at 11:22 PM.
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2020 Corvette of the Year Finalist (performance mods)
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maybe a coolant temp sensor starting to fail and showing lower than actual temp?... I can't think of anything else that would cause the fans to turn on sooner... if you had air in the system the car would run hotter than normal
Thread Starter
Safety Car
Joined: Jul 2010
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From: Chandler AZ
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Thread Starter
Safety Car
Joined: Jul 2010
Posts: 3,950
Likes: 386
From: Chandler AZ
DIC read 136 at start up and both fans appear to be running in low speed, took off cap to tank and then noticed level go down, added distilled water until back at line.
Letting it idle, squeezed hoses.
Will have to mess with it more in daytime.
Letting it idle, squeezed hoses.
Will have to mess with it more in daytime.
Thread Starter
Safety Car
Joined: Jul 2010
Posts: 3,950
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From: Chandler AZ
154 F with temperature gauge (digital probe type) in coolant reservoir, DIC says 198.
Probably useless information but I am measuring.
Fans still on low.
Probably useless information but I am measuring.
Fans still on low.
Last edited by 1999corvettels1; Dec 3, 2018 at 12:37 AM.
Thread Starter
Safety Car
Joined: Jul 2010
Posts: 3,950
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From: Chandler AZ
Before starting car DIC says oil temp 66, coolant temp 66, start car, fans running in low speed as soon as I got out of driver's seat to check.
Car had not been running since about 10pm last night, so it was a true cold start.
Any ideas?
Car had not been running since about 10pm last night, so it was a true cold start.
Any ideas?
Last edited by 1999corvettels1; Dec 3, 2018 at 06:31 PM.
Thread Starter
Safety Car
Joined: Jul 2010
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From: Chandler AZ
Mystery solved, that night before thanksgiving I was putting car and A/C back together, I put nitrogen into my A/C as I was tired and it was late.
Was going to let out nitrogen and evacuate that weekend but kept putting it off.
So I let the nitrogen out (woo hoo held good almost 2 weeks!) put the vacuum pump on, restarted car, fans not running.
Apparently the PCM senses high pressure and runs cooling fans, even with A/C off!
I had about 225 PSI in it the night before thanksgiving.
Was going to let out nitrogen and evacuate that weekend but kept putting it off.
So I let the nitrogen out (woo hoo held good almost 2 weeks!) put the vacuum pump on, restarted car, fans not running.
Apparently the PCM senses high pressure and runs cooling fans, even with A/C off!
I had about 225 PSI in it the night before thanksgiving.
glad you got it fixed though