91 RS overheat
#1
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Car: 1991 Camaro RS
Engine: 305 TBI
Axle/Gears: Open Diff
91 RS overheat
I have a 91 Camaro RS with a 5.0L TBI. I replaced the water pump because it was leaking out of the weep hole. I replaced the thermostat and radiator for weak flow. The heads have been professionaly done and the cooling fan works fine. Lately its been in the 90's and even hit 100 degrees here in illinois and if i have my a/c on for more than 40 minutes even on the expressway my car will start to over heat. Is there any way to fix this? Or is this just normal because of the load of the a/c compressor plus the extreme heat and the lack of a camaro having a grill?
Thanks
Ryan
Thanks
Ryan
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Re: 91 RS overheat
What about the secondary airdam directly under the radiator? And did you drill a steam hole in the thermostat?
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Car: 1992 Camaro RS
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Transmission: 700R4
Re: 91 RS overheat
Not trying to thread hijack here, but could you please elaborate on what you mean by drilling a steam hole in the thermostat? Don't think I have ever heard of that.
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Re: 91 RS overheat
Define "overheat".
If all it is, is coolant spewing, try a new radiator cap.
If all it is, is coolant spewing, try a new radiator cap.
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Re: 91 RS overheat
If you get a steam pocket under the stat, it'll never open. Then you have a parts-destroying overheat. So drill a 1/8" hole in the stat. Besides, it has the side benefit of not having trouble getting the cooling system totally full when filling after service. There are a few HP stats on the market that come with steam holes, but why pay triple for something scarce, that you can do yourself for free?
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Car: 1989-92 FORMULA350 305 92 Hawkclone
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Re: 91 RS overheat
Also make sure you got the correct reverse rotation waterpump.
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Re: 91 RS overheat
I fought overheating issues for a long long time. Living in Texas will bring out any weakness in a cooling sys. Tried a swapping radiators, thermostats, adding cooling fans, modifying the airdam, nothing helped. Installed a BeCool radiator and problem was finally solved..
I got the BeCool rad cheap from a guy that accidently bought it without the trans cooler (he had an auto trans). I installed a stand-alone tranny cooler with a built-in thermostat and cooling fan, so that probably helped some too.
BTW: The condition of the airdam is very important for highway cooling. They tend to get damaged since they are so low to the ground.
I got the BeCool rad cheap from a guy that accidently bought it without the trans cooler (he had an auto trans). I installed a stand-alone tranny cooler with a built-in thermostat and cooling fan, so that probably helped some too.
BTW: The condition of the airdam is very important for highway cooling. They tend to get damaged since they are so low to the ground.
#12
Re: 91 RS overheat
also one small thing to look at, something i just assumed could only run one direction before, if you have ever messed with your fans make sure theyre pulling not pushing. i wired mine up to a switch and always had an annoying 220-230 overheat, come to find out i was pushing. little switch of the terminals and good as gold.
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Re: 91 RS overheat
Make sure your air dam is all there. Also make sure you dont have any air bubbles in the coolant system. I had that problem temp went way over 230 on an aftermaket gage. 91CamaroRS/SS my trans am currently runs at 210. That however is the coolest I can get in and im in washington.
#14
Re: 91 RS overheat
Make sure your air dam is all there. Also make sure you dont have any air bubbles in the coolant system. I had that problem temp went way over 230 on an aftermaket gage. 91CamaroRS/SS my trans am currently runs at 210. That however is the coolest I can get in and im in washington.
210 is probably perfect if that motor is original to the car. My whole theory behind mine, its a GenII SBC and I think they would operate between 190-210. Mine however if I am driving around town alot will climb up to 220 - 225. And because I am using the rad that came in the car, I think thats why I cant get it to stay as low as I like. But im sure that the chips in my grille, making it look like a toothless hillbilly isnt helping much at all. Just my $.02
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