MikeM

We know nothing on the radiator, the fan or the clutch. That invites additional questions and discussions. Without that info,................................

0Tom@Dewitt

I am going to guess the radiator is a copper replacement, which doesn't help with this issue but until the OP contributes we can't do anything for you. I wish I new where all the people I helped with this issue are? During my days of tech calls I would talk about this 2-3 times per day. Often I talked the customer out of buying a new radiator until they ran my manual test. All most all the time they said I was nuts but would run the test, made the change, and then called back to tell me it worked. Usually it started with "you're not going to believe this but"....

Could this one be the combination of a bad radiator and lack of air flow? Sure, but what I am trying to tell members is that 9 out of 10 calls resulted in Vacuum advance issues when the conditions where straight up overheating at idle.

I know this isn't a Corvette testimonial but it is typical of what I heard at least a thousand times

I have a '67 283 SBC in my '30-'31 Model A Roadster. It has an R4 cam, HC heads, Edelbrock carb, and a Delco HEI dist. Car runs great and stays cool when moving. Problem was it would overheat when it had to idle for more than a few minutes. The coolant temp would climb 30 deg. in that time. It has an aluminum radiator and 5-bladed belt driven 15" flex fan. I was thinking a larger fan was going to be needed to move more air when stopped and idling. This would mean installing a new water pump housing to raise the fan high enough to fit the larger fan. I was even thinking about an electric fan.

Earlier on, a couple of days ago, there was a discussion topic on electric fans. As I was reading it one poster suggested the problem may not be air movement, but ignition timing. He asked where the vacuum for the distributor advance was taken. Was it taken from a ported fitting on the carb. or from a fitting that was exposed to vacuum? Suggested vac. to the dist. should be on the vacuum fitting not the ported one. Reason he gave was if timing is not advanced enough the engine will over heat when idling. By providing vacuum all the time the timing is advanced and the engine will run cooler.

My vacuum advance tube was connected to a ported fitting on the carb. I checked the timing and it was 10 deg. BTC. I adjusted it to 6 BTC, changed the tube to the vacuum port reset the engine idle speed back to 750 RPM. The timing with vac. on the dist. moved about another 10 BTC for about 26 BTC at idle. I let it idle away for 10 minutes and the temp only moved 5 deg. Much improved and it did not cost me a cent.

emdoller

I like this article that explains manifold vs ported vacuum.

Ed

http://chevellestuff.net/tech/articl...r_manifold.htm

MikeM

My '63 fuel injected engine in my car has no vacuum advance at idle. None until you open the throttle. It doesn't overheat and the spark advance is plumbed the way all of the fuelies were that left the factory.

It has the same fan and same radiator the OP's car is supposed to have.

No need for anyone here to defend their opinion. Not enough info yet.

MikeM

I just wonder if he is setting the timing with the vacuum advance hooked up or unhooked?

Mr D.

We didn't have the climate change back than that we do now.

GTOguy

Reducing the timing to smooth out the idle and reduce the popping from the side pipes when backing down from 55-60 MPH.....I've timed a lot of cars, but I've never used that technique/specification before. It's a sure-fire winner, IMO! Now, all I need are some side-pipes!

DucatiDon

New Aluminum Radiator, and Id wager you wont have any more problems.

Between Aluminum radiator, and a fresh aluminum head engine, I have no more heat issues.

Could you have exhaust gasses seeping into the coolant?

bowtyebob

I think that we covered just about every thing/possibility.
I was mistaken, my radiator IS an aluminum Harrison, cleaned and flushed and filled with the proper coolant.
Fab clutch works as it should. I advanced the timing today from 8 deg. (factory spec is 6 deg) to 10 deg. (vacuum line disconnected, of course)
Vacuum is non-ported from a vacuum port on the Holley 3810 (correct carb) showing 16+ degree at the port.
Thermostat is a 180 deg STANT Superstat.
Prolonged idling (about 25 minutes) in a 50 degree garage got the engine temp up to 210.
The owners manual (quoted earlier here) states that under normal operation the gauge SHOULD read 210 and that prolonged slow, stop and go driving can cause the gauge to read around 230. ....and that at 250 it is time to shut it off and find the problem. I'm thinking that I may have been worrying over a problem that doesn't exist.
At any speed over 40-45 the temp NEVER exceeds what appears to be around 190 even on a 95+ degree day.
I appreciate all the help and advice.
Thanks.
Bob

Nowhere Man

Depending if your raditor is a original unit or later service replacment it might not be cooling as designed. There is no way to fix or repair them. If the problem stays around save up and buy a new Dewitt’s

MikeM

Very well could be. Based on what was just posted, that car isn't cooling well whether it's idling OR driving.

If he's happy, I'm happy for him.