Cooling System

Guy Montaquila

Registered User
Hi Everyone,
I have had my coolant flushed twice hoping to get it to run cooler. My 90 SC gets to the high end of the NORM on the temp gage and it worries me a bit. It has the original radiator and fan. The thing is it runs at a temp that I like to see when I am just cruising along an open road. Is it possible that my fan is not running efficiently enough, or is it time to replace the radiator? Any thoughts, please let me know. Thanks for reading.
Guy
 
"The thing is it runs at a temp that I like to see when I am just cruising along an open road."

Don't really understand what you are saying in this statment. Please restate.

Jeff
 
While cruising, the air flow through the rad will keep the temp gauge around "NO" in "NORM".

The fan doesn't come on until 220 degrees, which is approx "RM" on the gauge. When parked at red lights etc, it will go up to "RM" and the fan will come on.

Your car is acting normal.
 
I think he means he's happier when it runs below the M.

I'm a original SC owner.. from the day I bought it, on hot days it has run consistently up to the "r" and slightly past it when sitting in traffic. After 160K Texas miles and a 2 water pumps, its still running fine. So, the fact that it might run hot hasn't been a problem... Oh.. and still on the orginal HGs :D

If you want it to run cooler, you'll need to do 2 things.. install a cooler thermostat and a manual fan switch.
 
Maybe look at fan

I am in TX too and I have had my 95 overheat on the freeway following behind a truck in a work zone at about 60 mph, just after replacing with a new cooler thrmostat and new water pump, new radiator, ALL new hosses, new HG, and fan tested fine- when idled it cycled on and off when it should. Fan did not come on everytime I discovered. Dealership tested it out fine after this incident and found nothing. I doubt you have this problem, but Check and see if the fan rotates freely. Bearings in mine were fine but the windings in the fan motor began to fry or something and eventualy locked up. It only ran occasionaly on low speed before I replaced it. Found original equip from Auot Zone and it solved that problem. The dealer will sell the $whole fan unit$, but you can get a motor aftermarket. Replacement is very little work.

Back pressure from old burnt Cats can make it run hotter too, as any number of things. The gauge in the dash can become calibrated dif., I have heard, if it ever overheated once.

I made the mistake of allowing a Ford dealer to replace my head gaskets and all above at just under 100K for free as there is a bulitin allowing that. Don't trust dealers with these cars unless the mechanic KNOWS SCs! Burnt valve now and doing work myself.

Doug

Note the number of Texan's talking about heat. We know alittle about it. Anyone had actual good results from rodding a radiator? Shops always recomend, but I have yet to hear of any real experience.
 
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Airflow, while I'm on the rag

I might add that some folks have said there is enough airflow on the highway with these cars. Based on my experience it is not true with a 94-95. Probably your 90 is fine. Another diference with 94/95 is the larger fan motor, I think to compensate for the further closing up of the front end, pinching off airflow. 96 front end opened up again.

Is your airdamn underneath still in tact? Are all the other airflow pieces still there? The mats love to come off.
 
That's assuming your air dam is intact below the front bodywork. Without it, not enough air gets directed to the radiator to be effective.

Below is a picture of one someone put on their car that was originally for a Grand Am. Unfortunately I lost all the part numbers.

airdam2.jpg
 
GM part #22635885

The article is in June 2001 Chargin' Thunder, titiled Otimizing Your Cooling System by Vernon Cradlier.
 
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one of the reasons im changing my 92 to a 94 front bumper is for added airflow to the radiator. on the 89-93 it has the small opening between the headlights, for airflow, it stinks. i think the 94-95 has a larger opening for better air, the 1996 is even better.
 
The intended air flow pattern for the t-birds is from under the front bumper, not through the front of the car. The aerodymanics of the vehicle are such that air flows around the bumper splitting into flows over, and under the car. With the air dam in place, the flow under is disturbed and much of it is routed through the radiator. That is why there is that rubber gasket like material that flows around the radiator except at the bottom, to prevent the air from taking an easier path over the radiator.
 
Hey I recognize that yard! Not sure that is a good idea either, I know Andy (the owner of the Blue car) has some cooling problems with that front end on his car (it also has the Xenon front air dam). Don’t know if he ever got that taken care of. Not sure whether or not he had a problem before but he did mention it to me when he was over last summer.

A little over 2 years ago there was a debate whether or not the fan was used while cruising. Several people thought that it was needed I said it wasn’t. If ford thought it was required then why even bother programming the EEC to shut off the fan when speed reaches 40 something miles per hour with the AC is running? Another question I had was since you can’t hear the fan running how do you know it is? To answer these questions I installed 2 LED’s one for the high speed fan and one for the low speed fan. I drove the car around for about a week or so and watched the LED’s. When I was going over 40mph the fan would not come on and the temp was low. My gauge would never even get to the N as long as the system had no air in the system. I drove to Austin from Houston in the middle of August without the fan coming on, except through Giddings where I got gas and some food. At that time the low speed fan would cycle about every 5-7 minutes. I also did some stop and go driving leaving Houston for Conroe (about 40 miles N of Houston) at 5Pm (read rush hour). The fan would cycle about the same every 5-7 minutes.

The high speed fan never came on, the only way I could get the high speed fan to come on (other than manually) was to remove the temp sender and heat it with a heat gun there was an audible difference between the low and high speeds of the fan. But this is the only way it would come on. My car is a 89’ 5sp, so I am not sure whether or not a 94-95 is any different, Have to see if Wynn or Vernon have noticed any of this with their “late models”.

Jeff
 
cut the 14 wire at the ircm.

change stast.to 18o or gut it out.............read other posts on heating and fan problems...FAST FREDDIE..:D :D
 
Heck, I swear we had a discussion on cooling years ago on the old board.

Part of the problem is that without some way to measure it, assumptions rule.

I don't think it's a question that Ford designed the early SC's to grab the majority of their air from underneath. Now weather the opening in the later models was to improve cooling, or just to change the look, I don't know. But still, with that bumper pushed way out there and it's shape, I'm assuming the majority of air is going to miss that grill opening.

I think one of the keys to the discussion in the past was air pressure, and that unless you provide a way for air to evacuate the under hood area, you could end up with hot air stacking up under the hood not allowing for cool air to enter the space and pass through the radiator. I don't think we ever got further than that.

The stock fan could likely be improved upon. And certainly the stock radiator can be.
 
Whatever.
I don't want to be a hard nose and pick at words, but I recall on another thread or something you mentioning that there is enough airflow on the highway without the fan. If not, please excuse me.

I really like a lot of what you contribute. But it isn't an assumption when the water boils out on a hot day when the fan doesn't work. Up North you never get the heat and humidity we do. I don't think a big study needs to be made, it seems a bit obvious to me. I am not going to defend what Ford did, just because these cars are so marvelous or something. It is full of compromises.

Well later, I said too much.

Doug
 
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