Alright I have and overheating problems.

I have a 1991 Camaro RS 305 TBI With Hypertech Chip Installed

New Parts

Water Pump
Radiator
New Fan 14" Installed Runing off toggle switch
New Temp sensor on the Intake & and the side of block

This car can sit and idle and run hot. I've tried to run with and without thermostat in it and it still overheats. When the car's at an idle it warms up and it will stay around 220 for a few mins then begins to overheat. I have flushed the engine to hopefully removing any blockages in the engine.

Things I havn't done yet check timming. The car fires right up without any hesitation and idle like a champ. I'm going today to by a thermometer to check and see if the coolant is really getting hot like the gauge is saying. Any help would be appreciated to narrow and fix this I really wanna drive this car. If you need anymore information let me know.

 

Is the 14' fan big enough to cool the car? When I bought mine someone had installed something simmilar and it could not cool it very well.

 

From autozone supposibly the 14" fan is an aftermaket replacement for the original fan. That's all they sell at this autozone.

 

An also it's not the heater core I bypassed that. And it was overheating before I did the bypass.

 

I would try a junkyard single fan. I have not seen an aftermarket fan that cools as well as an oem one.

 

Is it boiling over into the reservoir? If it's not, it's not overheating.

If it is boiling over try replacing the radiator cap first (like $3 at AZ).

Is the fan coming on and off as the engine gets to temp then cools down while it's idling?

Do not trust the factory guages.

 

Correct water pump?

JamesC

 

Yes the water Pump Is correct. There is a new radiator cap on it. It is boiling over. The timing is correct on the car. I took the after market fan off today and installed a flex fan 5 blade on it. It seemed to hold temp just under 220 at an idle not driven and and the thermostat is till out of it and today was an 85 degree day. 2 other things i did notice today was it looks like there's not a whole lot of flow I dunno if it's cause the new water pumps sucks or it's just the way it is at an idle. second thing I can collapse the top radiator hose completly but i can feel a little flow through it. As far as I know I have gotten all the air out of the engine. Pleas continue to help

 

clutchless flex fans are bad, you can find lost of post on the net where they let lose at even a mid range RPM and destroy everything in fornt of the engine, then come shootin out through the hood.

search for the tarurs fan mod, it will cool even a well warmed over BB......

 

So the pump is a reverse flow, designed for a serpentine system?

JamesC

 

Is the new fan mounted the correct direction for the reverse rotation pump? Put the thermostat back in and look in the radiator to see what the flow looks like.

 

Yeah I know the flex fans aren't the greatest thing to use but i'm going through trial and error here. When i first bought the car it had one on it and I changed it to electric fan wired to a toggle. The fan Is just not enough to cool it. It a true flo fan from autozone and it has to be tied to the radiator with them zip ties or whever u wanna call em. Now another thing I think autozone sold me the wrong water pump. It's flowing through the radiator but barely and the top tube I don't think i'm supposed the be able to collapse the hose with very little sqeezing pressure. I dunno but thinking about swapping out the water pump to they are only 30 bucks for a new one.

 

The serpentine belt system spins the water pump in the opposite direction from the earlier V belt system. It's easy to get them mixed up.

 

I would go back to a stock setup. Reverse flow water pump is a must. single OEM fan too. Keep the toggle switch until you figure the problem but I would switch back to having it automatically coming on. New 180 or 195 thermo cant hurt. It might be sticking. .

You dont want to run car too long with the resovoir over heating/bubling. As long as its doing that you still have a cooling issue.

 

may have the wrong type of water pump.

But the other thing I would suggest is to check timing and air fuel mixture at idle. that chip may have aggressive timing and with a lean mixture it could run alot hotter than normal.

 

Well i finally figured it out. I changed out the water pump and installed and new thermostat and installed a new flex fan. Most likely cause of the problem was the fan i got from autozone wasn't efficent enough to cool. So i went with the flex fan for now till I can get the cash up to get either a good single fan or dual fan setup. Problem sovled as of right now. It was almost 90 degrees today and it never went over 210 standing still at an idle. Thanks for all the help from everyone that responded to my problem. Thank you.