Overheating problem need HELP fast

[Gerry]

OK, my 67 rdstr and I have a problem with overheating and I am open to suggestions. I tested the car out the night before leaving to bring the car to Stahl and it was fine but it was a cool night and I did not sit idling for 30 minutes. The next day (92 degrees) while en route to Stahl headers in York Pa. in this I ran into construction traffic at multiple places. While the car (540CI/650HP Shafiroff engine 5spd Keisler trans) was moving at 25 mph or higher I had no problem (160-180) in fact the faster (100 MPH) the better (160 degree temp). Once it was stuck in traffic and stopped the temp climbed to over 230 before I shut it down. I have a Be Cool rad (but not the biggest one due to them removing it from market for redesign), 3350 CFM electric puller fan, 160 degree modified roberts thermostat (always some flow going thru it), stewert high flow aluminum water pump. The car is at Stahl Headers now so I will be limited with time and what I can do to it to solve the problem. Here is what I plan so far given my limited situation. Also, I know the headers will let it breath better as I had the stock exhaust manifolds on for the trip to Stahls but the problem is at idle when the car isn't moving forward.

1) I will try and install a 17 " flexalite mechanical fan in addition to the electric fan
2) I am going to use purple ice coolant additive
3) I will retard the timing to 30 degrees at 2500 rpm (It was set at 35)
4) I have the moroso restricter plates and can try the 1 " dia hole in place of the thermostat.

That's all I can think of right now. If anyone has any additional suggestions or thoughts please speak up.

Future ideas:
1) Also has anyone any experience with Evans NPG+ non water based coolant?
2) Can a pusher fan be mounted in front of the rad without cutting or modifying the car as I want to be able to return it to stock if necessary some day?

I have seen some pics of the headers and pipes from Jere S and they look nice.
Thanks for any and all help.

Best regards,
Gerry

 

[Subfixer]

Not sure what to tell you with the mods you currently have. Do a search for overheating and see if there was someone with a similar setup that got it fixed.

Grab a cup of coffee, there are a lot of overheating threads to go through.

 

[67HEAVEN]

Gerry,

It sounds like you've done everything right. It shouldn't be overheating.

If anything, my 502 runs a bit on the cold side. I installed an on/off switch on the dual Spal fans and the impact at low speeds is almost immediate. The coolant temp climbs very quickly when I shut the fans off.

First thing I would suspect is some anomaly in fan operation.

 

[Gerry]

Gerry,

It sounds like you've done everything right. It shouldn't be overheating.

If anything, my 502 runs a bit on the cold side. I installed an on/off switch on the dual Spal fans and the impact at low speeds is almost immediate. The coolant temp climbs very quickly when I shut the fans off.

First thing I would suspect is some anomaly in fan operation.

The fan comes on at 175 and seems to be pulling a lot of air thru the rad. Do you think the timing was too far advanced? I did not hear detoation but then I couldn't hear anything. Thanks for the help.

Gerry

 

[67HEAVEN]

The fan comes on at 175 and seems to be pulling a lot of air thru the rad. Do you think the timing was too far advanced? I did not hear detoation but then I couldn't hear anything. Thanks for the help.

Gerry

I'm running 12 degrees initial at 900 rpm (vacuum advance disconnected, line plugged) and 36 total. I'm using a MSD distributor with mechanical tach drive.

I agree. If you're satisfied that the fans are working okay, then on to timing.....but your numbers certainly don't seem out of whack.

How about bypassing your thermal switch for the fans to force them to run all the time? If that cures it.....something needs adjusting.

 

[JohnZ]

The fan comes on at 175 and seems to be pulling a lot of air thru the rad. Do you think the timing was too far advanced? I did not hear detoation but then I couldn't hear anything. Thanks for the help.

Gerry

The two most important things in idle cooling are airflow (which you appear to have) and ignition timing. The more you retard timing, the worse the problem will get. You want plenty of advance (vacuum advance, connected to manifold vacuum, with the correct vacuum advance can) at idle and low traffic speeds. You didn't say what you have for a distributor, what your base timing is, or what your advance curve is. Don't run it without a thermostat, and don't use Moroso restrictors; put a 180* Robertshaw (or the same one repackaged and sold by Mr. Gasket) in it; a 160* won't do anything for you - thermostats have nothing to do with operating temperature - they only control MINIMUM termperature, so the heater works in the winter. Forget the Evans thing - it's "snake oil" for a street-driven car.

You have enough radiator, or it wouldn't cool down when you're moving; it's either airflow or timing, or both. What kind of electric fan do you have? If it's just a round one with no shroud, it's only using half of the radiator (or less), and the other half isn't doing any cooling at all at idle.

 

[Gerry]

The two most important things in idle cooling are airflow (which you appear to have) and ignition timing. The more you retard timing, the worse the problem will get. You want plenty of advance (vacuum advance, connected to manifold vacuum, with the correct vacuum advance can) at idle and low traffic speeds. You didn't say what you have for a distributor, what your base timing is, or what your advance curve is. Don't run it without a thermostat, and don't use Moroso restrictors; put a 180* Robertshaw (or the same one repackaged and sold by Mr. Gasket) in it; a 160* won't do anything for you - thermostats have nothing to do with operating temperature - they only control MINIMUM termperature, so the heater works in the winter. Forget the Evans thing - it's "snake oil" for a street-driven car.

You have enough radiator, or it wouldn't cool down when you're moving; it's either airflow or timing, or both. What kind of electric fan do you have? If it's just a round one with no shroud, it's only using half of the radiator (or less), and the other half isn't doing any cooling at all at idle.

OK, I am using a MSD tach drive distributor with a 6AL MSD box and a MSD blaster II coil. The fan is a round one from Be Cool and is attached directly to the radiator with about 3/8 inch space between it and the radiator. I agree that the problem is airflow at idle. Before I swapped the engine and using just the original mechanical fan the car ran cold at 155 degrees. Perhaps I should put the original mechanical fan back in with the shroud and see what happens or try the flexalite fan which does not use a clutch. Thanks for the help, I just wish I had the car here to try stuff instead of at Stahls. Perhaps I will try and bring the car back at night beforer Carlisle and if I can fix the problem drive it back to Carlisle Thursday. Lots of miles (170 each way) but I don't think I have a choice.

Best regards,
Gerry

 

[JohnZ]

Gerry, I'd vote for the original shroud, fan, and clutch - they WORK - if you add more motor, just add more radiator cooling capacity, and you've already done that. I think you'll find that will solve your problem.

 

[midyearroadster427]

bring the car to carlisle and buy a dewitts big block radiator and your problems will be solved.....and John is correct with his assessment on the timing...the more advanced the more it will run cooler to a degree...

put on your shroud too.
i got a dewitts alum. big block radiator and i am stunned at the difference. i never had an overheating problem per se. but this radiator is amazing... i also use the reworked thermostat and have a stewart hi flow water pump. i have the rubber seal that ac cars use that blocks the air flow from going over the radiator too. the more air traveling through the radiator the better. and the shroud will increase the effect ...wind tunnel etc. good luck

 

[Gerry]

This is what I get for trying to reinvent the wheel or fan in this case. I will go to Stahls on Wed now and put the shroud back on with the original fan assembly along with the electric fan (this is a Spal 3150 CFM nascar fan) if possible. If not, I will try the flexalite fan, if still not possible then I will ditch the electric fan and go with original assembly or larger flexalite and PRAY. Thanks to all who have helped, this is just more proof that this list and the people on it are GREAT. See you at Carlisle one way or another.

Best regards,
Gerry