I’ve been having issues with 92 RS with a 305 overheating only with the hood closed. 230+ degrees and all the way to pushing coolant into the overflow if I let it. It has an edlebrock performer intake, aces fuel killshot TBI unit, 3 core aluminum radiator, sealed shroud with 2 12” electric fans controlled by the killshot ECU, 180 degree thermostat and new Dorman water pump. Ducting and air dam are intact. Fan control temp is set to 196 on and 192 off and I have no issues for quite awhile while driving until I sit in traffic for a bit or really drive the car hard and get up to about 205, once the cars at 205 it will no longer fluctuate coolant temp and will just slowly rise all the way to coolant boiling over if I let it. If the cars all the way at 230-235 and I pull over and open the hood, the temp shoots right back down to 195~ almost immediately. If I have the hood open, the car can idle pretty much indefinitely without an overheat problem. Anyone else had this issue and can give me some advise? I’m about to just cut some vents in the hood and call it good but if there’s a legit solutions I’d like to try that.

 

I recall someone on here having that problem,and the cause was radiator air was recirculating back to front with the hood down because side baffles for the radiator were missing.

 

This is from inside the engine bay on the drivers side. Is there supposed to be attentional ducting here?

And this is the ducting from in front of the radiator, it does have its side ducting here.

is there meant to be additional ducting on the sides of the radiator to seal it to the front/side ducts?

 

You have enough radiator there to cool a 12 cylinder tank engine when a stock style radiator that would have fit and bolted right in would have done the job.

The answer to your problem was given to you in your other thread when @ULTM8Z linked you to another guy having the same problem. I gave the solution to his problem in it.

I have done everything and it still overheats in traffic.

Everything takes the path of least resistance. Your car is also missing the sheet metal piece that goes from the front of your car to the core support. The way your car is setup now air is going to go everywhere but through the radiator.

 

I have a reproduction panel from hawks on order already for the front. I’ll make some block of plates for sides of the radiator and take the car for a drive to hopefully see a difference.

 

What car was this radiator supposed to fit anyways?

It's big enough to cool a Camaro with a 502 BBC with AC in Phoenix, AZ on a 115 degree day in stop and go traffic.

 

Is this the part you have on order?

Hawks Motorsports - 82-92 Camaro Front Filler Panel, Radiator Support/Hood Latch, New Reproduction

 

Yes that’s the part I had on order. Arrived today. Haven’t had a chance to install. And the radiator is a “direct fit” 3 core radiator. I fits in the lower mounts and it does also fit in the upper mounts except I modified the upper hold down and it’s not great. Once I make one out of aluminum it’ll be much better.

 

Direct-fit in Chinese must mean something entirely different than in English.

This is my stock unmodified 1992 Firebird. When you get done with your install the gaps should be this close or better. It's wet because I was washing it today.

 

I had high hopes for this as it was someone else’s solution but after putting some high density foam in the gaps (it’s ugly, I know) my problem persist, with what seems to be no perceivable change. I’ve sealed the gap between the condenser and core support almost completely and today (81 degree Texas day) driving home from work temps continued to climb to 228 until which I got home and let the car idle and the temp never came back down to the 194ish range. Just sat at the 226-228 range. I know that’s not “overheating” but I’m running a 180 degree stat and would much prefer a 210 and below operating temperature. Any other ideas I should give a try?

 

What all is done to this Hot Rod 1992 Camaro RS you got there?

13 to 1 compression?

3/4 Race cam?

5000 RPM Stall Convertor?

4.33 rear end gears?

2.0" primary tube full length race headers?

 

It’s a stock 305. Was a tune port, now has aces killshot throttle body injections. Edelbrock performer manifold and 180 degree thrermostat. Otherwise, stock as stock gets.

 

The stock cooling system that GM installed on your car in proper working order the way GM designed it to work on your car would cool your engine just fine. It would cool a 350 HP engine just fine too. You could even remove the cooling fans and as long as you were driving above about 35+ MPH or so it would cool your engine just fine and you wouldn't even notice the cooling fans weren't there.

If you car is running too hot driving down the road at 55+ MPH then you got something all messed up from the way GM designed it.

 

On this 81 degree day today when driving back from work how hot did it get while moving at speeds above 35+ MPH?

 

Does the Aces Killshot fit under the stock hood or do you have an aftermarket hood? And.. how do you like the Aces Killshot so far?

 

It’ll only fit under a stock hood with the standard performer intake or similar and a 2” filter element. I have maybe 2mm from the wingnut. The killshot isn’t bad but it 10000% takes getting a professional tune and you’ll have to learn to make adjustments yourself also. It’s really designed to work on larger cubic inch engines with more airflow demand. The smaller and less aggressive the engine, the more tuning it’ll need and you may have some small drivability issues to work out.

 

Does your Camaro have the stock hood and the cowl to hood weather strip in place? At slow speeds below about 35 MPH not having the weather strip in place will let the hot under hood air flow out easier but as speed increase above about 35 MPH the hood, cowl, windshield interface become a high pressure area and it forces air backwards into the engine compartment fighting against the air that's trying to enter the engine compartment from the front of the car through the radiator. This creates "dead air" in the engine compartment and without airflow the cooling system wont cool the car. Having the hood to cowl weather strip removed also allows hot under hood air and fumes to be sucked into the air intake of the HVAC system for the cabin compartment of the car. Making the inside of the car hotter and stinky.

This is how a factory cowl induction hood works. The hood is sealed to the cowl, the opening in the back of the cowl induction hood allows the engine to take in much cooler outside air and do it under slightly increased pressure and the bottom side of the cowl induction hood is sealed off from the engine compartment and ducts the air into the air cleaner assembly through a seal. As your speed increases the pressure builds up at the hood, cowl, windshield area and gives a slight supercharging effect.

Can you take some more pictures under the hood giving a full view from the front and sides, view of the gap between the condenser and radiator and the top cover plate and radiator, view looking down into the front with the cover panel you ordered from Hawks removed, view from underneath of the air deflectors, baffles, and ducting?

 

100%

Can your run it up to ~210 or higher and then shoot various places w/an infrared temp gun and report back? I'd look at t-stat housing, hot inlet of rad, middle of rad, outlet/lower hose of rad....for starters. While the engine is running, hot and fans are on.

 

Ran






ran out of time at work to take more pictures unfortunately. What is stumping me is with the fans on I can feel a ton of airflow and paper or plastic will get sucked right into the front vents, with that much airflow I don’t see how it can’t cool efficiently enough to keep the temp near the 195-200 range with a 180 degree thermostat.

 

I agree. But fan flow aside, fans don't matter going down the road. It should cool way better than good enough, going 35+ down the road....with NO fans...as airwolfe already said.

Temp gun.

 

This guy makes the upper radiator bracket that you need. His car even has the exact same 3 row radiator that your car has.

He is a fellow 3rd Genner like us. Made in America in North Carolina.

I don't know this guy from Adam. It looks like a nice quality piece. He makes them in different sizes for different radiators and makes them with custom logos too.

9K Motors

 

You are missing the mounting hardware to attach the airflow guide on the bottom. Some airflow is going on top of the airflow guide on the wrong side of it to do you any good. At speed it may be deflecting downward causing even more of the airflow to go over the top side of the airflow guide.

Do you have a part number for or a link to where you bought this Dorman water pump you installed on your car? It's possible you got the wrong rotation water pump. Our cars with the 1988+ serpentine accessory drive system require a reverse rotation water pump.

 

I agree with the water pump suggestion.

I think the worrying about air flow "leaking" around the radiator is mostly, as I like to say, "Worryin' about chit that ain't worth worryin' about". I think the affects of that leakage are negligible in the big picture. Diag is in order. I would do that w/a temp gun.

 

Dorman?

Might be a good idea to check it and see if it even has an impeller.

 

Got a chance to work on the car some today at work. I pulled the thermostat from the housing and used a power flush gun on the cooling system to clear out any contamination and old coolant. I filled the cooling system with thermocure and water and let the car run for about an hour and half with a bleed funnel. Without the thermostat, idling, with the hood up, it settled in at about 174 and just held there with both fans running constantly. Cleared out the thermocure and water with the power flush gun again, installed a 160 degree thermostat, vacuum filled the cooling system, installed a bleed funnel and raised the front of the car with the lift to ensure no air pockets. After about 30ish minutes of holding around the 176~ mark, it began to rise very slowly to 183~, this is where the cooling system has seemed to lose its ability to regulate temperature. I used a temp gun and checked directly at the coolant temp sensor in the manifold, about 179~ (variation a few degrees could very well be my temp gun), at the drivers radiator tank about 3 inches below the hose I had a reading of 160~ and the passenger side radiator about 3 inches below the cap had a reading of at 150~. I checked which water pump I installed and was mistaken when I said Dorman, it’s a Gates 43114. Listed as a serpentine belt impeller water pump so I don’t think water pump direction is my problem either. On the drive home from work the coolant temp continued to rise very slowly until I reached the house where it was at 203. About 1 exit worth of highway driving and light traffic off the highway, at no point did moving about 35mph help decrease temperature. I’m going to try and get ahold of my old coworker and see if I can borrow his thermal imaging camera to get a full picture of engine bay and radiator temps all together.

 

If I'm reading this right, you got ~183 in the cylinder head (as indicated by your coolant temp sensor/cluster gauge) and at roughly the same time, you're reading ~150 going into the water pump. To ME, water's not circulating (fast enough)

 

The serpentine drive system is all stock except for an air pump delete, this is the correct belt routing yes?

175~ read at the temp sensor. 185 in the digital gauge

Upper hose temp

140 about 3 inches below hose inlet on drivers side

131 about 2 inches below cap

166 at lower radiator hose about half way between radiator and water pump.

Pressure tested system again. Found no leaks. Held pressure at 18psi. Block tested again and passed again. Verified no air in the system. Does not seem to be an airflow problem considering highway driving doesn’t help at all. But also can’t find any signs of failed head gasket or cracked head. At a complete loss. I had an overheating problem when I first bought it, since then I’ve changed the entire cooling system and still have an overheat concern. I feel like I have nothing left to suspect other than the engine internally.

 

Sure looks like a v-belt,CW rotation WP in the pics with the capped off heater return port on top-do not recall seeing that on '88 up CCW water pumps.Also pulley bolt circle is smaller on the CCW pumps,so if pulley bolt holes have been modified that is the reason. Weak circulation from wrong pump should have same effect hood up or down ...

 

I checked the part number for the water pump he bought and it is a reverse rotation water pump.

 

How about the right part number on the box but the wrong rotation pump inside?

 

I looked at all my '88 up SBCs and found my '91 G30 van has a pump that looks like the subject one - Has the top fitting,but no alty bracket lug. Correct for CCW rotation....

 

A lot of butchery going on in there, who knows.

 

IDK.....that REALLY looks like a lack of coolant flow to me. Sounds like you've confirmed that it's not the wrong pump. I guess at this point, I'd pull the stat out and try it....or pull the pump and look at the impeller and/or see if it pumps water. You're showing 175 at the neck, and a drop to 160 at the upper hose nipple?? What cooled the water 15* in the 2' rubber, upper hose? Hmmm....

Then your 130* on the cold side tank, but 166 on the cold side/return hose? Hmmmmmmm.....That lower hose water his being heated by heat transfer from the engine, IMO. Should be the same temp as the cold side tank.

 

I run a fleet maint shop, I have 10 techs....we've had ^That^ problem twice in the last two months; temp rising out of control, good cooling fan performance, cold rad core....HOT engine. In both cases, I asked my techs, "Are the thermostats in backwards?" Both were taken aback and told me (correctly) how the stats should go into the engine. In both cases, the t-stats were, in fact....in backwards/upside down. So. There is that to check....

 

Well. I loaded a pretty expensive parts cannon and yanked the heads. Between both side of 17 head bolts, 1 bolt had water intrusion. The side with water intrusion through a head bolt hole also has 2 valves that have been replaced previously. Putting on another set of 081 casting that have been gone through at the machine shop with felpro 1094 gaskets. Found a lot of loose/incorrect bolts a previous owner as well. Should know soon.

 

Pics 2 and 3 sure look like head gasket seeping compresson between those two middle cylinders-head likely warped pretty bad to do that on a 305.Should run nicer when back together