Overheating when ac is running

[86camota]

So, I live in the great city of phoenix. Nice, dry, and hot. Well, heres my problem, when i drive, and get kinda stuck in traffic, the temp gage starts to go up, but when i turn my ac off, the temp goes down. What would be causing this? My guess is rad. cap or thermostat.

thanks

[atobe]

are the fans running when the ac's on ? i don't know if the 86 had dual fans or not

[86camota]

You know, I'm not sure. I'll check it out after i get off work

[Mike Gerber]

If not the fans my guess would be a partially clogged radiator that can not dissipate the extra heat caused by the a/c. How many miles are on this car? Is the radiator original? You can remove the radiator and have it flow tested at a radiator shop. Call around to a few radiator shops in your area and ask if they do this and what the cost would be.

Mike

[86camota]

Not sure about the radiator being the original or not. Mileage on the car is roughly 173000

[66conv6]

I had the exact same problem when I lived in Phoenix.

The a/c fan is supposed to come on any time the a/c is switched on. I only had the other fan coming on instead of both. Car would start to overheat in stop and go traffic but not necessarily on the freeway.

[86camota]

Originally Posted by 66conv6

...Car would start to overheat in stop and go traffic but not necessarily on the freeway.

Well, it happens when its rush hour on the freeway, so somewhat stop and go.

So question, is it easy to link both fans together and have them run together off a switch from inside the cabin?

[66conv6]

I used to drive every week from Los Angeles to Kingman,Az with a partially plugged radiator. The car would get real hot on long uphills. I ran a large wire from the non working fan to the interior of my car (driver's floormat) and another from the car battery. The two wires ran into a fuse holder I bought at the car parts store. The fuse holder would just lay near the interior floor and I would plug in a 30A fuse to turn the fan on if the temp gauge started climbing. I did this for a few months til I could replace the radiator.

Then I had troubles with tires coming apart a high speed during summer but thats another story!

[white90dx]

Originally Posted by 86camota

Well, it happens when its rush hour on the freeway, so somewhat stop and go.

So question, is it easy to link both fans together and have them run together off a switch from inside the cabin?

You can easily test to see if both fans are working by unplugging the fan temp switch located on the water inlet neck (under the alternator, single wire plug covered by a rubber boot).

With that plug unplugged, both fans should be running at high speed. When the A/C compressor is running, both fans should be on at low speed - at that time, they are wired in series (6V for each fan) unless the water temp gets too high or the A/C line pressure gets to high.

I ran ran a pair of wires to the A/C dual pressure switch (you can also do it with the water temp switch) and used a switch to open the circuit to turn on the fans while drag racing (switch on/connected = normal operation, switch off/open = fans on).

First, just check to make sure both fans work, then go from there. You may have a clogged radiator or a partially stuck thermostat if the fans are working.

-Charlie