Best Remedies for Running Hot???

Smkn600ctd

Registered User
My buddy has a 95 SC auto, bone stock...........and lives in Vegas where the 100 degree heat has begun. However the SC is not liking it one bit.

Running around town and on the the highway it will flicker the Check Gauges light, the gauge will just about touching the red zone. It does not boil over, and the fans are one. I've checked it with a infra-red therm, at the low is on all the time with the a/c on, and the high comes on at 228 degrees along with the secondary fan.

He went and got a aux. fan controller that he wants me to wire to the secondary fan, and have it come on at 190 degrees to help it out. Is there side effects (CE lights etc,. ) from just cutting the wires and running my own to the extra fan to be controlled by the fan controller???

I don't think its enough, cause the low speed fan is on anyways.

Radiator...new
Water pump....new
Thermostat....160 degree and new.
Doesn't lose coolant.
Runs like a raped ape.

How are your guys keeping yours cool in the summer heat with the a/c on?????
 
Oil cooler and radiator are the two places to check

Oil cooler and radiator cooling is suspect.
  1. Check your oil cooler to see if it is clogged? Run good synthetic oil and change is every 3000 miles.
  2. When did you last change your coolant? Use water wetter’s with distilled water adding enough anti-freeze to do the job as needed.
 
Don't forget to check that the chin spoiler and lower radiator skirt (from bottom of radiator to sway bar) are still in place.

Also check the overflow hose to the tank to be sure it isn't blocked and confirm the temp gauge sender push-on connector is clean/tight.

Other items are common to most cars...pressure check system & radiator cap (right one for the system?); test water/coolant mix %; check heater operation for hints of trapped air.

That 160 deg. stat seems awfully low....
 
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When swapping to a lower t stat, it's recommended to get a tune. Most people usually only go down to 180* but without a tune, your car can actually run hotter because you havent changed you fans on temps. But if your re-wiring the fans your self...will that work, I don't know.

Do a search for 180 t stat and you'll see many threads about running hot, changing t stats etc.

Good luck!
 
Don't forget to check that the chin spoiler and lower radiator skirt (from bottom of radiator to sway bar) are still in place.

That chin spoiler... you wouldn't believe how much of a difference it makes... it can be the difference between overheating and just running hot. On my track car, I was almost overheating after a few laps, I inspected my aluminum 1.5" wide spoiler and noticed it had bent under. Straightened it out, angled forwards and the car never ran that hot again.

I also take one additional step and that is to seal the gap between the bumper cover and bottom of the radiator to deflect more air up. The difference is amazing.. its worth about 10 degress of cooling. :cool:
 
When I got my car it had a "hot air intake". I fabbed up a box around the cone filter and now the temps are a lot lower. It use to run at the R in noRm. Now it is between the N and O in NOrm. I know it isn't very scientific, but it has worked wonders for me.
 
My gage use to run in the "M" before the fan kicked in but, not anymore. It's weird.

Radiator and water pump is new.
Stock Thermostat
I changed the coolant last summer. The solution is of Distilled water, 1 bottle of water wetters and some coolant (about 60% distilled water). The new load has about 4000 miles on it. I didn't run it over the winter, just started it up and drove around the block on nice days.

In the city, the car always ran in the "M" before the fan kicked on until recently. One day I noticed that the coolant overflow was a little bit low. I added some coolant. Now the temp gage never gets above the "R" before the fan comes on. Gage might be flakey, I don't know but I'm guessing I had an air pocket that finally worked itself out.

Good luck with yours!
 
Reseat the sender wire from the sensor at the thermostat.

If everything is working as it should, then the only other option you have (unless you want to start cutting wires) is to get a chip. Then you can run a 180 tstat and have the tuned adjusted for it, including fan on temps etc.

Fraser
 
Reseat the sender wire from the sensor at the thermostat.

If everything is working as it should, then the only other option you have (unless you want to start cutting wires) is to get a chip. Then you can run a 180 tstat and have the tuned adjusted for it, including fan on temps etc.

Fraser

However,be aware that on the 94-95s,if you run the puller fan excessively you run a very high likelihood of ending up with a melted mess in your fuse box...I ended up with a melted mess in my fuse box within 60 miles of adjusting the fan via a chip to run more
 
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Switch to a 180 thermostat. 160 is too low, and if your guy ever goes to the mountains the car may never warm up. You can check the thermostat before you put it in using a pot of water on the stove and a cooking thermometer.

As already stated, make sure you have a chin spoiler under the front bumper, if not, you loose a lot of cooling capacity as the chin spoiler works to create a low pressure area behind the radiator, improving air flow. Magnum Powers makes a unit that works really well.

Are you sure the second speed on the stock fan is coming on? It has a low speed, which should be on with the A/C and then a high speed, that should come on as the temp goes over around 220f. My guess is that the high speed winding isn't working on the fan.

A note, pusher fan effectiveness is much lower than a puller. Make sure the puller is working right before messing with the pusher. And if you do take control of the pusher with your own controller, make sure you run it's own power line from the battery, don't tap into anything. Fans take too much juice and need their own circuit.
 
Stock fan settings is 220F for the low speed, and 228F for the high speed... and if its a '94 (only a 94) then the pusher fan at front should come on as well as the high speed mode of the puller fan. '95's keep the puller fan at low speed but the pusher fan still comes on for "high" speed mode.

The older cars, only have a puller fan with 2 speed's with the temps as stated above.

Fraser
 
That water wetter may just blow your mind. But if the car set for any amount of time it will leak out.
 
Take out the stat and remove the center

THE SPRING & PLUG GET A 9/16 S.S. FLAT WASHER:eek: USE SOME COOPER SEALENT TO HOLD IN PLACE:) THEM REINSTALL STAT YOU SHOULD RUN COOL FROM THEN ON..:D IT'S A 50'S TRICK JUST ENOUGHT FLOW TO COOL DOWN MOTOR :cool: HAVE BE USING IT ON MY 90 SC FOR 5 YEARS NOW THE TRICK IS TO KEEP THE COOLANT IN THE RAD JUST TO GET COOL THEN PASS ON TO MUCH FLOW NEVER GETS TO COOL SO THAT WHY YOU DON'T TAKE :( OUT THE STAT:p
 
He went reading on here and searched other articles. We did the #14 wire to #17 wire trick and went for a drive.

MUCH better. Only heated up to the M on a 8 mile grade at highway, then right back down to just below the N.....see how this works for a while.

In the winter time, I'll just reverse it for him if need be.
 
Mine used to read hot and I replaced thermostat, radiator cap, etc.
Never could figure it out, it never boiled over.
The car sat for several years (couldn't drive it because of ABS issues).
Then it never read above cold.
I replaced the temperature sending unit and all has been fine.

It's a cheap part, get one and see if that doesn't settle it for you.
 
My 90 SC used to run hot...

I have a 1990 SC that used to run hot. The fan wouldn't kick on until the temp read M on norm. After doing a little research I cut the #14 wire as that seemed to be the easiest solution. This worked well for about 3 months. Then one day I was driving and smelt smoke and when I came to a stop I saw a glimpse of smoke come from under the hood. I immediately pulled into the first parking lot I came to and opened the hood. My fan motor was actually on fire. Luckily I was parked next to a puddle... I nursed it home stopping and letting it cool every time the temp came up (long drive home...). Changed the rad fan and seemed to solve my problem. I'm considering putting a toggle switch on the dash to open the circuit for the number 14 wire to run the fan only on hot days when i need it. I live in New York near the Adirondacks and don't see much sense in running the fan all the time. Plus I'm worried that I might burn out another one.
 
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