Page 2 of 2

Re: overheating

Posted: September 17th, 2020, 1:00 am
by Red Horse
overflow tankhttps://psp.pontiacstreetperformance.com/download/file.php?mode=view&id=1254&sid=1b8009b67ed35b3c31137b05ec7f3eb1

Re: overheating

Posted: September 17th, 2020, 1:04 am
by Red Horse
overflow tank

Re: overheating

Posted: September 17th, 2020, 1:10 am
by Red Horse
I don't know if the photo of the tank is posted. It shows up on my PSP page as being posted tho. I'm not even sure how I managed to move it off my phone.
Rich

Re: overheating

Posted: September 17th, 2020, 11:34 am
by Admin
Rich, photos can be uploaded from a smart phone. Kiwi Mal did it in this thread.
https://www.psp.pontiacstreetperformanc ... hp?f=3&t=1

Re: overheating

Posted: September 17th, 2020, 3:07 pm
by Admin
AA334283-8A39-41C7-A1E9-1AC4975D6237.jpeg
Rich—-Here is a photo taken of my boy dog with my smart phone camera and posted from my smartphone. Here is how to do it. You did do it; here is clarification if you need it again.

Go to the internet on your phone and put in the url for the forum. Then log in. Go to the overheating thread and proceed by adding attachment by adding file and select the pict to post.

Bill

Re: overheating

Posted: September 17th, 2020, 3:17 pm
by Admin
Looking at your overflow tank, it is on the driver's side of the radiator. I assume the neck of the radiator and cap are on the passenger side. Does the hose run in front of the radiator to the bottom of the tank?

Do you have a fan shroud in place?

Re: overheating

Posted: September 19th, 2020, 12:58 am
by Red Horse
Tank is on drivers side hose in front of radiator to bottom of tank, fan shroud in place.
I noticed while the engine was warming up above idle rpm the temp stayed with in acceptable range. When dropped down to idle rpm temps started to climb again. Which is makes me think the fan pulley is too big.
I may have to put things on hold, i just got a big bill for my boat diesel.So no money for the Firebird.

Re: overheating

Posted: September 22nd, 2020, 9:46 am
by Brian R
I wrote an article about this on the old site but not sure how to find it.

I had similar problems and all of what has been said above it correct.

Below is a sort of "checklist."

In order:
* Timing
* Thermostat
* Cap
* Aluminum radiators are the best - a good 2 core with true 1 inch tubes works the best but a factory style radiator should also work
* Good pump
* Clearance between radiator and shroud - there should be NO air gaps. This should be a tight fit as air will always take the path of least resistance. If you have gaps, the air flows much easier between the gaps than it does through the radiator
* Crank Pulley
* Fan Clutch
* Fan type and size. You mentioned it had been a 6 cylinder car, you may have a small fan. Clutch fans are by far the best. Flex fans work for some but not others - therefore, if you are running one, get rid of it. Measure the diameter of your shroud and get the LARGEST factory style clutch fan with the most blades you can find
* Fan placement: The fan has to be half in the shroud and half out. If it is in too deep or totally outside the shroud, the airflow will not suffice
* The MOST IMPORTANT: Clearance of the dividing plate. The guy who built my engine swore he clearanced it correctly so it was the last thing I did.
I pulled it apart and found a huge gap. (anywhere from 1/8 to 1/4 inch) Pound it down until it is damned near touching the impeller. The gasket will open the gap slightly. I love Pontiacs but the waterpump/divider plate design is terrible. Close this gap up as much as possible.

Pontiac used several radiators, fans, pulleys, etc. based on the Car, Engine, AC, non-AC, etc. Use the heaviest duty you can get and it will run nice and cool.

Example for my car: 71 Lemans, originally a 350 AC car w/ 273(?) rear. Now, no AC, 461 stroker, 3.55 rear. This engine is much larger, rear forces higher RPM's, turbo 400 tranny instead of the original turbo 350, etc. Like yours, always crept up to 230 and if in heavy traffic I would have to pull over to let it cool. Drove me nuts. I did all of the above with varied results at each step. Finally, clearanced the divider plate properly and now with a 180 thermostat, it rarely gets above 175. In very heavy stop and go traffic on a 90 + degree day, it may get to 190. I love it! Been this way for years. One time it got hot, thermostat was bad. Pulled the thermostat completely and drove home at around 200 degrees. I put in a new one and back to running cool all the time. Thermostats do go bad ...

I do not recall the diameter of the pulley I put on or the diameter and number of blades of my fan. I will check tonight.

Re: overheating

Posted: September 22nd, 2020, 4:48 pm
by Red Horse
I have a new Champion,next thing is to go to the 69 1/2 year model change on the water pump, And the clutch fan.
Looking in the repair manual the number of fan radiator combinations is challenging. wanted the radiator as specified for hi performance 400, but couldn't find one. Fan is the correct size but not a clutch fan.
The radiator could use some sealing on the sides.

Re: overheating

Posted: October 1st, 2020, 10:37 am
by TAMAN
I had that problem but I knew I ran cool before. I had an air bubble. I raised my front end up high and ran the engine for 10 minutes. Saw the burp and that was the end of my cooling issues. Now I run 160.

Re: overheating

Posted: October 7th, 2020, 12:25 am
by Red Horse
I'll give the burp solution a try , thanks
Rich

Re: overheating

Posted: October 11th, 2020, 5:08 am
by Red Horse
I tried the burp solution, either I didn't have the nose high enough or there was no airlock . This car has never run cooler than 190.

Re: overheating

Posted: November 13th, 2020, 10:28 am
by Admin
The last time you posted (11 Oct) , the overheating issue was still unresolved. It's a month later. have you solved the problem yet?

Bill

Re: overheating

Posted: November 15th, 2020, 1:10 pm
by Red Horse
Hi Bill,
The over heating issue has not been resolved.I have to solve issues with my sailboat before I can pursue the car problem . Too many toys I guess.The next thing to resolve the overheating is to install a smaller diameter water pump pulley . I also want to install a lower baffle as used on the a/c cars.If I can find one.

Rich

Re: overheating

Posted: November 20th, 2020, 3:28 pm
by TAMAN
My problem was a air bubble in the heads somewhere. I was running 210 cruising and 220 at a stop light. Raised the front end up 8" and let it run for 5 minutes. Now I'm back to 160 running temp. Even in traffic on a 90 degree day.