Overheating on my 65

[Chris H.]

My 65 is overheating. I've had the radiator professionally restored, installed a new hi-flow water pump, diluted the anit-freese, added water wetter, had the entire engine professionally rebuilt ($6,500), tried numerous fans (I'm back to the original 7 bladed fax and HD clutch) and I keep overheating. I've run out of ideas. Any help will be appreciated

[Tom H.]

Re: Overheating on my 65

Dumb comment here, but are you sure it is truly overheating ?? or are you watching the gauge ?? Is it boiling over ??? Just asking.

[Edward J.]

Re: Overheating on my 65

Chris, need alittle more info,does the car overheat while idling, driving down hwy., have you used anything to measure the water temp. (ie- infared gun, thermometer) .sometimes the the gage may not be accurate.
Do you see water overflowing from radiator? feel the upper hose when car is fully warm - is the temp. of hose about the temp. of the themostat you installed . (this check for thermostat opening and closing).

[Joe L.]

Re: Overheating on my 65

...I've had the radiator professionally restored...

Chris----


How was this done? The radiators used on ALL 1965 Corvettes were aluminum, stacked plate design and are, essentially, not restorable as to functionality.

[Chris H.]

Re: Overheating on my 65

Dumb comment here, but are you sure it is truly overheating ?? or are you watching the gauge ?? Is it boiling over ??? Just asking.

Tom, thanks for asking: Good point, but I've had the guage peg at the 240 mark a few times and when it does, the car starts to buck, miss, and kill. It appears that the intake gets so hot we're guessing the gas in the carburator is vaporizing.

[Chris H.]

Re: Overheating on my 65

The temp guage continues to rise the slower we go. If I get caught in traffic on a hot Denver day, I have pegged the guage and the car bucks and comes to a stop. I have to let it cool down before i can effectively restart it.

[Edward J.]

Re: Overheating on my 65

Good question Joe,there not the restoreable type even when boiled out.

[Chris H.]

Re: Overheating on my 65

Well that's interesting Joe. Now you have me wondering. The radiator was in the car when i got it years ago. When I took it into a radiadator shop here in the Denver area, he told me it was as iron core unit. It's the correct fit as far as I can see. I presume aluminumn cools better than an Iron core unit. Your thoughts.

[Edward J.]

Re: Overheating on my 65

Chris its either alum. or copper and that could be if replaced as aftermarket replacement.

[Joe L.]

Re: Overheating on my 65

Well that's interesting Joe. Now you have me wondering. The radiator was in the car when i got it years ago. When I took it into a radiadator shop here in the Denver area, he told me it was as iron core unit. It's the correct fit as far as I can see. I presume aluminumn cools better than an Iron core unit. Your thoughts.

Chris----

I have never heard the term "iron core" used with respect to automotive radiators. The only iron radiators I know of were used in old homes with steam or hot water heating systems. All Corvette radiators were either copper/brass or aluminum from 1953 right through the present day. I don't even know of any REPLACEMENT radiator that's iron. A photo might help us identify what you have.

[Chris H.]

Re: Overheating on my 65

Thanks guys. Maybe i missunderstood the guy at the shop, but he did indicate that he was able to repair the unit that was in the car and if it were aluminum, he could not. I think you and Ed may be onto something here as I've tried just about everything I can think of. Do you think an aluminum unit would run cooler?

[Edward J.]

Re: Overheating on my 65

Chris, maybe one more item, when the high flow water pump was installed, did you change any pulleys,alter anything else that may slow down the water pump pulley, I believe that 65 is a year that always has alot of questions on correct pulleys, What do you think Joe L ?

[Chris H.]

Re: Overheating on my 65

I might also add that I know the radiator in the car is not the original as "Harrison" is not noted anywhere on it.

[Chris H.]

Re: Overheating on my 65

Yup, we put new pully's on the car as we went to a two belt design (Long story), I've been wondering if we changed the ratio and need to go back to the guy who rebuilt my engine.

[Edward J.]

Re: Overheating on my 65

Chris, check to see if on the water pump theres a flow direction indicated and check the belt to see if its going in the right direction, sometimes these pumps are make for cars with serpintine drive belt systems that rotate in different directions.