Cooling problem opinions?

[93 teal terror]

OK heres my prob. The car will not overheat with the a/c off but will get to about 220 or so in stop and go driving. With the a/c on the car will continue to overheat in traffic, but I usually cut it off by 225-230. On the highway the car will get to about 190-200 with the a/c on and 190 with it off. The car has a 180 degree thermo. and the radiator and water pump are about 2 years old. Brass 2 core radiator and stock replacment pump. The fan clutch was replaced with a new one but it was not the heavy duty one. The car has underdrive pullies on it but the alt. one isnt on currently. Is it just as simple as getting a heavy duty clutch or should I look at an electric fan. If I remember correctly when the car overheats in stop and go driving the fan is the culprit and at high speeds or both the radiator may be the culprit.
Any opintions are appreciated.

 

[90mustangGT]

Your correct, this is a fan issue more than likely. How much air is the fan blowing with the engine at operating temp? You should feel a warm wind, meaning the air should be warm and you should be able to feel real airflow. Also, check to be sure your getting a good temprature drop between the upper and lower hoses.

 

[sgarlic]

You're correct that if it is overheating on the highway it's most likely not a fan issue. The fan basically free wheels and just sort of blocks incoming air passing through the condensor/radiator on the highway. Many agree that the "ram air effect" of 35mph+ speeds are enough to cool the radiator with no fan, and I tend to agree. I have the taurus fan/dcc setup in my '88, and at most speeds higher than 30, it never comes on.

For one thing, with the A/C on, your engine is going to have to work a little harder to maintain the same output, but you shouldn't have rising temperatures that don't go back down if your fan/water pump, etc, is working as it should. If you're sure the t-stat is ok, you can basically rule that out as a problem. Potentially, I would think the fan clutch you got may not be up to par cooling wise. A standard fan clutch (regular duty) usually spins at 50-60% of pully speed when fully engaged, whereas a heavy-duty clutch spins 80-90% when fully engaged.

If your coolant mixture is correct for your climate, your fan shroud is in tact, and you don't have a blockage of radiator or heater core, or air in the system, I would think trying the heavy duty fan clutch may help lower your temps. Worst case, you can probably try the heavy duty clutch, and if it doesn't work, just clean it up a bit and return it. Many reputable auto stores are ok with that sort of thing so long as you don't put several hundred miles on it. Good luck.

 

[93 teal terror]

Thanks guys, I may just go ahead and try a new clutch if its under a 100 bucks. I think the last one I bought was 30 or 40, but if i remember correctly the heavy duty unit was a bit more. If its too expensive I may just try the electric fan setup from a jy.

 

[HISSIN50]

Well said everyone. Also, how is your fan blade doing? The plastic stockers like to crack, which makes it kinda useless.

The HD clutch and a metal fan blade are hard to beat when talking mechanical fan set ups. It gets hot and muggy in the Research Triangle area.

As an aside, most newer cars have a provision that shuts the electric fan off at a given speed (usually 35-50 MPH).

Good luck.