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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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AC causes car to over heat

  • Thread starter Thread starter bdemat
  • Start date Start date Jul 15, 2020
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Dan02gt

mazing how much gas smell came from that tiny hole
20+ Year Stangneter
Mar 2, 2003
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Greenville, NC
Jul 20, 2020
#21
  • Jul 20, 2020
  • #21
Did you make sure no one installed under drive pullies on it at some point?
 

KRUISR

10 Year Member
Apr 16, 2015
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Jul 20, 2020
#22
  • Jul 20, 2020
  • #22
I agree with General karthief, your fan and shroud look fine. The fan needs to be in the cylinder section of the shroud. If it is not it will not pull air. Yours is fine.

Looking at the pics, how old is the rad and how thick is the core?

I would get a very small screwdriver or thin putty knife and try to clear that paint out of your condenser.

Another thing to check if your A/C is charged enough, when car is idling with A/C on Max does the clutch stay engaged for long periods of time. If not (it cycles on/off often) you likely are low on refrigerant. I just did this on my truck. It was same thing, cooler when moving and less cool when stopped. I added a 9oz can of refrigerant to my truck and now will blow cold (will get down to 6 degrees Celcius out vents).
 
Last edited: Jul 20, 2020

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
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polk county florida
Jul 20, 2020
#23
  • Jul 20, 2020
  • #23
I bet you have two problems
#1 ac low on feon
#2 you may or may not have an overheating problem, you need to put a mechanical temp gauge on it to see actual temp numbers, you can zip tie it to the wiper arm temporarily.
It would not be unusual for the engine temp to get to 210-215 sitting still with ac on.
And I'm betting you have under drive pulleys too.
 
B

bdemat

Member
Sep 22, 2018
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Acworth ga
Jul 21, 2020
#24
  • Jul 21, 2020
  • #24
Dan02gt said:
Did you make sure no one installed under drive pullies on it at some point?
Click to expand...
No underdrive pulleys. I am really at a loss at this point. Everything looks like it should be good. I am changing the Ac clutch bearing because it makes a lot of noice but i dont think it will make a difference.
 
B

bdemat

Member
Sep 22, 2018
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Acworth ga
Aug 2, 2020
#25
  • Aug 2, 2020
  • #25
So i am on my second fan clutch,,i don't know the exact temp , my cheap temp gauge says its 210 when i point it at the thermostat housing. And the clutch is not engaging. Possible 2 new clutches are bad? Or maybe the water isn't circulating through the radiator at idle fast enough?
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
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Aug 2, 2020
#26
  • Aug 2, 2020
  • #26
Is it stay'n at 210* or does it keep going up?
 
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bdemat

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Sep 22, 2018
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Acworth ga
Aug 2, 2020
#27
  • Aug 2, 2020
  • #27
It was still going up
 

LX Dave

5 Year Member
Jul 2, 2017
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Aug 2, 2020
#28
  • Aug 2, 2020
  • #28
Just went through this with my car, even though I don't have AC, it would run really hot while idling.

Engine - Another cooling system thread

Hey guys, I'm having an annoyance with my '84 Mustang. When going down the road, the cooling system has no problem keeping the engine cool (normally runs between 197-203 degrees) with a Motorcraft 195 thermostat. The problem starts when I have to sit and idle for more than a couple of...
www.stangnet.com

Even though I had a new fan clutch on, it was new bad. Details in the thread what brand I was running and where I got a good one.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,929
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203
polk county florida
Aug 3, 2020
#29
  • Aug 3, 2020
  • #29
I think 220* sitting still with the ac on would not be unusual, point the temp gun at the bottom of the radiator near the lower hose.
Temp measured at metal parts will be a few degrees higher than coolant temp. I've used a meat thermometer between the shroud and the radiator.
 

Mindseye007

10 years still blowing strong
5 Year Member
Oct 21, 2020
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ontario
Oct 21, 2020
#30
  • Oct 21, 2020
  • #30
I had a similar problem I fixed it by getting a flex a lite electric fan installed https://www.flex-a-lite.com/direct-...-electric-fan-for-1979-1993-ford-mustang.html my overheating problems are solved are you running underdrive pulleys? I run underdrive pulleys with no problems at all.
 
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