hi
i have searched all the post about the subject and have found out that most of the time the problem was because fans were not working. I have this overheating problem with the a/c on, but i only have one fan. I think my problem is that the a/c compressor is creating too much drag, for whenever the compressor is engaged the whole car vibrates and with the hood up you can hear the compressor dragging. My question is that is it overheating just because there is only one fan? My a/c system has never had anything in it since ive owned it, so i added r-124 with that cheap retrofit kit just to see how it would do about a month ago. My car without a/c runs around 190-200 but with the ac on it will climb to 240 in a matter of minutes. any help would be appreciated.

P.s. also if i run my ac on max for like 20 seconds, then turn the a/c off, then turn the car off, the car will not shut off unless i turn the ac on, then it will shut off immediately. im pretty sure this isnt normal lol

 

Seymourless, hows about some specs on your car like year,make, model, engine,trans, options, miles, etc? Does the fan look factory or like an add-on? Also, measure the diameter of your fan.

 

oops sorry, its an 86 z28 auto tranny fuel injected. the fan looks stock but only takes up about half of the radiators size. i feel that there is suppost to be a fan for the condensor, but there is not. i just drove on the highway cruising at about 3200 rpms and the engine stayed around 180-190. I turned the a/c on for 3 minutes and it was just below the 220 mark. Also, is my fin under the car suppost to be at an angle or parralel to the ground. mine is parrallel.
thanks again for any help

 

Does your fan come on with the AC? Is the compressor shot? How's the system cool? Is there any debris between the condenser and radiator? The air dam is parallel to the ground.

JamesC

 

Hey Seymourless, is your engine a 305 or 350? I hav`nt found info yet that tells me whether yours came with one fan or dual, I suspect one.

 

its a 305, with max ac the air comes out pretty cold, but nothing like a new car. there is no debris that i can see between the condenser and the radiator, but i will look more into that. my fin underneath the car is perpendicular to the ground, strait 90 degrees. im not sure if the compressor is bad, i am assuming that it wouldnt be since it is blowing out cold air, maybe the clutch is going perhaps?, since when the car is on the whole car has a vibration shake to it, but it does cycle normally. There is a big difference in throttle response when i have the compressor running, which would mean it is dragging the engine down. i only have one fan that runs all the time, guy before me has it set up wierd, but keeps the engine cool when running normally.
thanks again

 

Seymourless, you can try and adjust the lower air dam on more of an angle, I don`t know if it would help or not. If you hav`nt done so, go over every part of your air cond. and make sure the brackets etc.e tight and the belt is in good shape. You should see some drag with the air on but if using your air causes a lot of performance issues, it needs some work. When is the last time you serviced your air?

 

Basics to check for are:
properly working radiator cap, radiator and coolant
working air dam
Clean dirt and blockage off radiator and condenser
make sure the fan shroud(s) are there if your car came with them
make sure your fans are blowing the right way ( stick some paper in front of the condenser and turn the fans on. You want to make sure the fan holds the paper in place, NOT blowing it away

Then....
I had the same heat up problem on my 86 tpi trans am for a long time. It would slowly heat up with the a/c on. I had 2 new aftermarket electric fans that were not doing the job. I finally got it to run just right when I changed the electric cooling fan to a newer factory style. I took the complete dual fan assembly out of a 94 trans am and jammed it into the old 86, it runs fine now

 

Seymourless, you might consider a 4th gen dual fan set-up. I just got a 4th gen dual fan shroud for my `88 Iroc from Hawks and can`t wait to get it installed. I was stuck on the freeway today in 100+ heat and I was running 220-240 with the stock dual fans. If you decide to go with a dual fan set-up and need a shroud or other parts, call or e-mail Bruce at Hawks. He has done a good job for me.

 

thankyou for all this help, my last question is if this isnt the problem, that maybe the compressor clutch is dragging too much on the engine...how could i really check this? i only have one fan that runs all the time for the radiator, no fan for the condensor. is there suppose to be 2 if my car came with a/c? also i replaced the fan motor like 6 months ago so i think its doing its job ok, shroud is in place. i might try and get a new plastic fin though for under the car, looks like mine is bending a little backwards lol

 

Seymourless, I could be wrong but I think GM started putting the dual fans in `87 or `88 f-bodies with air. Your overheating would be a good reason for them to have made the switch. If your car overheats in stop and go traffic, the problem is most likely the fan, if it runs hot while driving it is probably one of your air dams (fins). Check your lower one and if it is loose of bent too far back it should be easy to see where it should be connected. Actually, your temps don`t sound out of line, they are about where they should be for factory parts, you are running the same temps I do with my `88 Iroc dual fans.

 

Help, I have a 1987 IROC 2ith the 2 fan set. I am replacing the motor for the fan and I need to know which fan motor do I replace that come on when the car reach the correct temp? Thanks

 

IROCU2, If I understand you correctly, the primary fan is on the driver`s side of the car so that is the motor you need.

 

Seymourless, I know little to nothing about air since this is the first car with air I have had since my `71 Charger I bought in `73. No, don`t still have it, wish I did. I do know that when I turn on my air, there is a noticeable drag. I don`t know if a newer model compressor would be any different, I suspect they would be some better. You might throw that question out there on the air conditioning forum on this site.You might also stop by a few air conditioning shops and ask their opinion but don`t let them sell you anything you don`t want or need. You might also try the "search" function at the top of the page on this site. I would guess your single fan is about 16" ? The lower air dam can get bent backwards from running into things,mine was bent back so I pulled it forward and secured it with some heavy duty wire ties. I get a bit more clearance and it works better.

 

The one that doesn't work.

JamesC

 

JamesC, great catch there.

 

I should have been more specific. But thats ok I have them working now. Turn out to be the motors (both) needs to be replaced. I tapped on them with a wrench and they came on, so that tells me its time for replacement. Thanks for all the help guys.