High Temp Under Load

hoffmandj

Registered User
My coupe is heating up @ 2000rpm under heavy load, for example up hill. I believe that I have a flow proablem with my radiator or water pump. I just wanted to here what you guys think. My coolant is clean, so I have no indication of blown head gaskets, but maybe a hair line frature in the head allows some heat from the combustion chamber to get into the water passages somewhere, and under high presser the heat is escaping into the passages. Just an educated guess butt who knows.
 
I have had HG's leak just as you described before. They would only leak hot gases into the cooling jacket at higher RPM such as highway driving but driving in and around town everything was normal and you would not suspect HG's.
Try driving at the RPM you notice this happening at until your temps start rising alittle then pull over and pop the hood, check and see if your overflow bottle is bubbling.
If it is I would go to Autozone and borrow a cooling system leakdown tester and install it on the radiator and pressurize the system. If pressure drops you have a leak in the cooling system somewhere. First look for any obvious external hose or gasket leaks. If anything on the outside of the engine is leaking you will see it once you pressurize the system. Once you have done this and cannot find any external leaks but are still losing pressure your HG's are leaking.:)
 
Overheating

It seems to me that all cars reguardless of whether it's an SC or not will warm up when under heavy load. How high does the temp go? If it does not go above the "M" in normal I would not be overly concerned. The high speed fan comes on right around that temp. Up until about 15 years ago cars came with 180-190 deg t-stats, but with the emissions control required these days they have to run a lot hotter. Most of the (newer) cars on the road today are designed to run at 212-220 and are very happy at those temps. If it conceerns you that much get a fan switch and adjust the fan so it comes on sooner.

Later..........M
 
Most of the (newer) cars on the road today are designed to run at 212-220 and are very happy at those temps.This is just not true. Cars today are meant to run around 195 deg. 212-220 is too hot.

If it conceerns you that much get a fan switch and adjust the fan so it comes on sooner.
This is just a makeshift way of dealing with the problem. Its not the answer.

Up until about 15 years ago cars came with 180-190 deg t-stats, but with the emissions control required these days they have to run a lot hotter.The first part of this statement is true most all cars were equipt with 185 deg thermostats, today there equipt with 195 deg thermostats. Thats not alot hotter but is a far cry from 212-220. ;)
 
Thanks Guys

The heat up rate is not norm. As soon as I start up a hill it starts heating up and travels past the m in norm. My fan is already on a toggle switch because the fan relay in my powertrain controll module is burnt up.
 
heat

i duno man, my 89 SC normally runs a little warm..... i would say a little bit above the dead center on the gauge. feels really hot to the touch.... like takes the skin off hot... but its ok.

when under load it remains the same.... does not warm up....
cools down when i go fast :p so i try to go fast as much as possible.

if yur not having any leaks or anything, thats a good sign, so i would try flushing the radiator and running through some zerex flush or something, then putting in all new fluid, be sure to run the motor too to clean that out, then slap in a 180 temp T-stat or hell, even a 160 if you dont drive it in the colder weather..... EVER.

good luck, Adam
 
If you are sure the system has been purged of air. Get your radiator flushed or replace it. It should be running plenty cool in this parts with the daytime highs in the 60s.
 
Probable answer

This summer I was having the exact symptoms on my 90SC. 115+ temps here in Arizona at the time. Around town no problem. Climb a hill and it would immediately heat up and within 5 min would be past the "m". If I didn't stop within another 2 min it would trigger the check guage light. Now, this was a new problem. I did all the diagnostic, fan working, etc. etc. Put on two GM air dams all to no avail. I worried about hg's but didn't have any of those symtoms. My radiator visually looked to be in great condition, as I've always religiously changed coolant. However, I replaced the radiator with a new copper/brass one from Radiator Express (price not much more than having your radiator taken apart and rodded). Problem solved!! I could climb any hill as fast as I wanted to go and the temp stayed about "r" on the hottest of days. Bottom line is I think I clogged it up myself by using water out of the garden hose. High alkali content around here. So I've learned my lesson, no more hose water, only distilled for me from now on. John
 
MIKE 38sc said:
Most of the (newer) cars on the road today are designed to run at 212-220 and are very happy at those temps.This is just not true. Cars today are meant to run around 195 deg. 212-220 is too hot.


My stock SC ran a consistant 220-230 degrees and higher in very hot and humid weather. The fans come on at 222(low speed) and 230(high speed). So if in fact these cars aren't meant to reach such temperatures why are the fan settings so high, would it not make sense for the low speed to come on around 195 and the high around 210?

These engines run hotter than your normal NA motor. They are designed to run in a temp range higher than most cars I've seen.

I've driven my SC with both stock and modifed engines and the temp is almost always around 220 under normal driving conditions.
 
This is probably an isolated incidence, but...

I had EXACTLY the same prob with my '90 AOD.

The TV cable to the trans had been mis-adjusted causing way too much pressure. I'm not a tranny guy so I can only tell you the results. On a steep upgrade it did what you described and finally started to slip in OD. I had to have it rebuilt and all the clutches were burned to 'ell.

Lee
 
Bluethunder90:

My stock SC ran a consistant 220-230 degrees and higher in very hot and humid weather. The fans come on at 222(low speed) and 230(high speed). So if in fact these cars aren't meant to reach such temperatures why are the fan settings so high, would it not make sense for the low speed to come on around 195 and the high around 210?
I dont dispute the fact that your car is running that warm. I'm just saying that it is not good to run that warm. I realize what temps the fans are oporating at but the ideal cooling system would very rarely have to turn the fans on period. What would make more sense than anything would have been for Ford to install a cooling system that could more than easily take care of cooling this engine but instead they cut corners on it.

These engines run hotter than your normal NA motor. They are designed to run in a temp range higher than most cars I've seen.
I agree with you here but what I do not agree with is that this engine should normaly run hotter than the NA engine. High heat is the enemy to any engine the fact that this engine has a blower on it does not mean its an exception to the rule, if everything is as it should be this engine would run no hotter than the NA engine.

I've driven my SC with both stock and modifed engines and the temp is almost always around 220 under normal driving conditions.I wonder what your oil temps are running at with your cooling system running that hot......Ever think about that?


Hoffmandj:

The heat up rate is not norm. As soon as I start up a hill it starts heating up and travels past the m in norm. My fan is already on a toggle switch because the fan relay in my powertrain controll module is burnt up.I'd be willing to bet that your rad is partialy stopped up thus reducing flow. That is a very common problem with this tiny rad Ford sold us. The rad is sized so close to the line of being adaqeute(spelling) that any tiny problem with a component in the cooling system puts you in danger as far as engine temps go. If your stock cooling system 100% perfect you dont have too bad of a problem but if your system is say 95% good you have problems. Now you throw a hot tranny cooler in the rad tank on top of this and things go to hell pretty quick.
 
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