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Re: my 1990 runs above 230 degrees (25/35)
 9/26/13 8:40pm
anthony.digirolamo
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Joined: 9/11/2012
Posts: 10

 The Coolant fan relays are on the drivers side of the radiator (2).  1 wire from each is the ground which turns the fan on.  On 90's the primary fan ground is light blue with black and the secondary fan is dark blue with white.  Strip some insulation from each wire and wrap some # 16 wire on each separately and run to two toggle switches you have installed somewhere convenient inside car (knee bolster?)  Run one or two wires to ground.  I use the horn ground.  You can turn on either or both fans and the ECM will still turn them on also.


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Re: my 1990 runs above 230 degrees (26/35)
 11/5/13 11:56am
POOLPUMPREPAIRGUY
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Joined: 11/5/2013
Posts: 11

stacking fans can be tricky, and my car had a plugged bleeder tube, the one that comes off of the top of the radiator (one the dealer I bought the car from couldn't figure out) I used speedo cable and a drill to clean min out and it fixed the cars over heat issues. NEXT  I installed a mechanical thermostat for the fan, have been doing this for years on most all of my cars, the fan is hooked up to run at set temp and runs when car is shut off, lowering engine compartment temps. the trick is to install the thermistor at the bottom of the radiator, this allows the fan to run for about a minute after the car is shut off. installing it around the top of the radiator is not a good idea. 

also I hear that the temp sensor is on the head, and should be on or around the stat itself, the head location gives bad readings. i have got the new 3 wire temp sensor but have not installed it yet, I would like the wiring diagram or how to, if someone has it ?


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found the bucket grommets for my 2002 headlights on ebay
Re: my 1990 runs above 230 degrees (27/35)
 2/22/14 12:04am
Smokey
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Wills Point, TX - USA

Vette(s):
1992 C4 Pure 100% stock


Joined: 2/20/2014
Posts: 6


What is the best way to get at any debris that might get between the condenser and the radiator? Do you have to pull the units all the way out or can you get at it and clean it out while on the car? I live in Texas and the summers get HOT and humid. My '92 Vette does as some others have said here. On summer days at 103-105 degree temps the car runs about 200-207 on the road and at a stop light it gets up to close to 230+!  Oh yes I do hear the fans coming on and always when the air is on.

Any help here would be appreciated.



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Re: my 1990 runs above 230 degrees (28/35)
 2/22/14 3:19am
POOLPUMPREPAIRGUY
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Joined: 11/5/2013
Posts: 11

never gets that hot here in florida, I use commercial condenser cleaner. that can be found at Grainger, and Ice32 a additive that seems to lower head pressure,

variable orifice tube

now I installed one of these on my 90 gm 4x4 1500 truck and it has preformed very well with 134, but have not used one on my vette yet, it's got 120,ooo miles on her now and this summer I will be installing a new compressor, and will install one, at that time. you must make sure your ac is working at peek performance, as this is a significant heat source that can cause RUN HOT issues (driveability) 
you can only do so much, before a total dissemble is required to remove and get like new clean, 
Remember you have a emergency radiator, it's called a heater core and has saved me many times in all sorts of vehicles, just crank up the heat and set the blower fan on high, not much fun but beets a overheat situation. best of luck hope I was of some help. Jay .. 95 convertible, top down and ac crank'n baby Thumbs Up    


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found the bucket grommets for my 2002 headlights on ebay
Re: my 1990 runs above 230 degrees (29/35)
 2/22/14 3:35am
POOLPUMPREPAIRGUY
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Joined: 11/5/2013
Posts: 11

what I use is a electric fan thermostat control, the relays are on the drivers side of the radiator, and I have been doing this for years with all of my vehicles here in florida, it allows me control of the fans, and I hook it up so when the car shuts off the fan can run and cool the engine compartment off,(runs for about 2 minutes) just remember to install the thermister (probe,bulb) LOW on the radiator. If you install it on the top of the radiator, I will guarantee a dead battery is in your future.
this is a cool trick that has served me well for 30 years in central florida.
Top down ac blast'n baby Thumbs Up.. jay .. florida


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found the bucket grommets for my 2002 headlights on ebay
Re: my 1990 runs above 230 degrees (30/35)
 6/21/15 9:35am
vet-vette fish
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edgewood, NM - USA

Vette(s):
92 lt-1 6 speed 163000 miles prior about 12 to 15 vettes


Joined: 6/20/2015
Posts: 4

I HAD THE SAME PROBLEM.  I INSTALLED A NEW CHAMPION RADIATOR FROM PERFORMANCE RADIATOR. ALL ALUMINUM 3 1 INCH CORE AND VERY REASONABLE.  PROBLEM IS SOLVED.
Re: my 1990 runs above 230 degrees (31/35)
 6/21/15 9:38am
vet-vette fish
Former Member

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edgewood, NM - USA

Vette(s):
92 lt-1 6 speed 163000 miles prior about 12 to 15 vettes


Joined: 6/20/2015
Posts: 4

LIKE YOUR IDEA AND PROBLEM SOLVING SOLUTION.  I WILL USE THAT ALSO. THANK YOU
Re: my 1990 runs above 230 degrees (32/35)
 7/13/17 4:03am
molotov
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Joined: 7/12/2017
Posts: 22

Don't care if these motors are designed to run hot.. I haven't got the b*lls to run at these temps as you don't get a lot of warning of impending doom!
 
My fan failed a few years back, and the temp went really high past 250deg and dumped all the coolant out the expansion tank in a heartbeat.
 
..so,
 
It got a new fan, new water pump, new hoses, new rad cap (with a valve lever to burp air out safely), a thermostatic fan controller set for 90deg and a 160deg thermostat.
 
Now, on the hottest days here (37deg), I seldom see the temp over 185 even at 70mph on the motorway here in the UK or in slow traffic.
 
Be cool..
 
 


|UPDATED|7/13/2017 1:03:27 AM (AZT)|/UPDATED|


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Re: my 1990 runs above 230 degrees (33/35)
 7/12/17 10:10pm
Dave91TM
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Joined: 6/17/2012
Posts: 12

Been through the overheat thing. I replaced the rad with a stock rad and it now runs cool all time.
Cost was $250 did the work myself. We drove the Majove desert at 104 degrees outside, Temp guage
did not get to 1/2. Look for something simple first, before you get into adding switches and changing thermostats
and fiddling with fans. The rad that is in there is 27 years old, they gum up. Good luck



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Re: my 1990 runs above 230 degrees (34/35)
 7/13/17 4:16am
molotov
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Joined: 7/12/2017
Posts: 22

Forgot to add that I replaced the radiator too and dumped all the AC kit and just replaced the pump with an idler. Didn't mind that as it was part of my weight reduction obsession on my '87 anyway.
.


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Re: my 1990 runs above 230 degrees (35/35)
 8/7/18 2:52pm
Willy
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, - Canada

Vette(s):
1990 Steel Blue Metallic coupe


Joined: 8/29/2015
Posts: 3

Install a relay switch to activate the second fan.  I have never had a problem with overheating since

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