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Discussion Starter #1
my car runs cool all the time except if im in low speed traffic or sitting idling with the AC on. once i get moving it seems ok

the car usually stays at the first small mark on the guage but when the ac is on and im sitting still or not moving fast the gauge climbs toward the halfway mark


im just trying to get an idea of what i should look into fixing it. the car has no problems idling when the AC is off, in fact if the car heats up and i turn the ac off it cools back down, even sitting still

anyways the car has a brand new griffin 31x19 radiator
and the stock clutch fan seems to be working correctly

couple other things, the car has 93 cobra crank underdrive pulley and water pump pulley. i know these cant be helping but its just odd to me that it would only do it with the ac on

oh yeah R134 conversion on the AC

any ideas?

BTW 1990 lx hatch, 93 cobra motor with F303 cam, etc etc
 

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<<its just odd to me that it would only do it with the ac on>>

AC on makes it a lot harder to cool. Cooling air is heated by AC condenser and then this air must cool radiator. Like sitting in 110 deg heat with AC off.

When the car is moving, you don't need any fan.
 

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Your fan clutch is probably toast. Pull it off and check for any fluid leaks.

Also how thick is that radiator? The fan might be too far inside the shroud to work properly. If so you can space the fan back or simply trim the fan shroud. You want about 50-60% of the fan to be outside the shroud.
 

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Discussion Starter #4
yeah i did a search on this and the fan spacing was one thing i found. how do i space the fan back?


i do have another fan i can put on to see if it makes any difference. the clutch should be good on it

blown88, i understand what your saying and it makes sense but how would i go about fixing the problem? i doubt very much the car was intended to overheat from the factory with the ac on, what makes it different now?
 

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Mike Gager said:
yeah i did a search on this and the fan spacing was one thing i found. how do i space the fan back?


i do have another fan i can put on to see if it makes any difference. the clutch should be good on it

blown88, i understand what your saying and it makes sense but how would i go about fixing the problem? i doubt very much the car was intended to overheat from the factory with the ac on, what makes it different now?
Here's the instructions:

Remove the fan & clutch assembly from the car, then on the workbench remove the fan blade from the clutch - save the old bolts that mounted the fan. Replace thes bolts with grade 8, 5/16-18 1.25" bolts (try your local hardware store)., as you install each new bolt place two 3/8" nuts on each bolt after the bolt
passes thru the fan, these nuts act as spacers. You will generally only require 2 of them per bolt to give the 3/4" spacing needed. The next challenge is getting the fan/clutch assembly back into the water pump pulley - it is a very tight fit with not much room to maneuver the bolts. I put all 4 bolts into the clutch shaft flange and *ease* the whole assembly very carefully into position getting all 4 bolts started a few turns before snugging any of them down, then you tighten each bolt a few
turns and go on to the next etc etc
When I used this method I found the fan to not sit square with the clutch because of the loose tolerances on the nuts. This caused it to wobble a lot. So I bought some precision spacers from McMasterCarr. Just go to this link and chose your material:

http://www.mcmaster.com/param/asp/psearch.asp?FAM=spacers&FT_218=43625&FT_103=194&session=desc=Spacers;spacers;218=43625;103=194

The spacers got rid of the wobble and the car cools great in stop n'go with the a/c running. This is in 100+ degree CA heat too.
 

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i have cooling probs too. i have fluydine rad, new water pump, 180 thermo. jus replace the 195 i had it for like 2 months. nothing seems to work it stays around the middle at 55 or better under 45 it climbs the the top. i also have an electric fan which i only run when stoped. what gives????
 

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URIN2ND said:
i have cooling probs too. i have fluydine rad, new water pump, 180 thermo. jus replace the 195 i had it for like 2 months. nothing seems to work it stays around the middle at 55 or better under 45 it climbs the the top. i also have an electric fan which i only run when stoped. what gives????
Which fan do you have?
 

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Mike Gager said:
... i doubt very much the car was intended to overheat from the factory with the ac on, what makes it different now?
What is different? Your Griffin radiator...much thicker than stock...harder to pass air through it.
 

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Discussion Starter #9
jester, thanks for the instructions, i will give that a try


blown, the same thing happened when the car had the stock radiator and a ron davis alluminum. only thing is it would run hot almost all the time with the stocker and would damn near boil over when the ac was on
 
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