C2 Cooling Issues

[Bruce Boatner]

I apologize if this subject has been beaten to death. I have a 1964 327/300 with factory A/C that runs around 180 to 190 degrees until I switch on the A/C, at which point the temperature rises to around 210 to 220 degrees. I believe the temp. gauge on the car is fairly accurate. I am not sure what type of radiator is in the car now, but suspect it is not the original aluminum style radidator--Is there a quick and easy well to tell what type of radiator I have? I have read good things about the DeWitt replacement radiators but not sure if this is gospel or hype. I sure would hate to plunk down $700 to $800 without seeing much of a difference. I live in Texas and drive the car daily. I want to be able to run the A/C in 95+ heat and not worry about overheating (if this is possible!) Probably a stupid question, but could I expect better cooling from the A/C if the engine runs cooler?

Thanks for you input.

Bruce

[Craig S.]

Re: C2 Cooling Issues

Bruce - the DeWitts is a great radiator and will address your cooling. This is like the GM Harrison aluminum radiators, stacked design, no end tanks. It is very easy to see the difference visbily. Old and plugged Harrisons are not a great thing either, I have one in my 67 now that is coming out and the DeWitts is going in. Since the air going through your condensor is cool since it mounts in front of the radiator, I would not think there would be much effect on the AC. Instead, the AC causes the thermal temp to rise in the radiator and aggrevates a bad radiator...Craig

[Bruce Boatner]

Re: C2 Cooling Issues

Craig--Thanks for your input. Looks like I will bite the bullet and by the DeWitts. I guess $800 is cheaper than a new engine, not to mention what I will save in laundry bills in the summer.

Quick question, I plan on buying new upper and lower radiator hoses, but are there any other parts I should have on hand while the radiator is out of the car? For example, rubber supports at the bottom of the radiator or anything like that.

Replacing the radiator seems like a fairly straightforward job, but are there any tips or pitfalls I should be aware of?

Thanks so much for your help.

Bruce

[Jack Layton]

Re: C2 Cooling Issues

Given the ambient temperature of 95 degrees and operating the A/C, I do not think 210 degrees showing on your gauge is too high. Without running the A/C the temperature of 180 is dead on and one must expect the temperature to increase if the A/C is opereated.
You did not say that you had any "boil over" problems. So why the concern about an absolute temp of 210 ? Are you getting cold air in the cockpit ? Has the rest of the A/C system been checked ? The DeWitts are an excellent product but have you determined that you truly need one?. What happens if you spend the $800 and the temperature gauge shows no significant change ? I suggest you collect more data and perform a valid analysis of your needs.

[Bruce Boatner]

Re: C2 Cooling Issues

Jack--OK, now I'm paranoid again--what to do, what to do. I just bought the car about 3 weeks ago and I cannot honestly say that I have operated the A/C for any length of time in 90 plus degree heat. I drove the car in moderate traffic in 85 degree heat with the A/C on and the temp. gauge was a movin' on up fairly quickly. I chicken out after the gauge passed 210 or so, shut of the A/C, and commenced sweating. The fact that the rubber boots on the shifter are cracked allowing amazingly hot air to enter the cabin with surprising force did help matters. After switching off the A/C, the engine temp. drop by 20 degrees or so fairly quickly.

I may gather up my manhood a little and see just how hot things get. I am getting reasonable cool air in the cockpit, but it is hard to enjoy it in a constant state of paranoia.

[Joe L.]

Re: C2 Cooling Issues

Bruce------

Look for the number "3155316" stamped into the top of the radiator. If it's there, you have an original radiator which may have degraded by now, to one degree or another. If there is no number and you notice the presence of side tanks, then you have a copper/brass replacement. I would recommend replacing this with a DeWitts original style alumiunum radiator; it definitely WILL increase cooling capacity substantially over a copper/brass replacement for the 3155316.

Also, I agree with Jack---your reported engine operating temps do not seem out of line to me. So, I really don't think that you have a cooling problem currently.

[Wayne P.]

Re: C2 Cooling Issues

This subject has been beaten to death. There are numerous things that will cause overheating in addition to the radiator. Check the archives for a LOT of pointers.

[Joe C.]

Re: C2 Cooling Issues

Bruce:

Don't spend your money on a new rad. unless you are sure that is the problem. Tom DeWitt makes a great rad., but check your timing, fan clutch, lower hose first. You said that as soon as you turn off the A/C, the temp drops rapidly back to normal. That sounds like the rad has enough capacity to quickly recover. Try this test. Let your car idle for awhile, and when your temp is stabilized at normal, then feel the rad core at various locations. There should be a slight variation in temp from top to bottom. Variation should be fairly even, with top being hotter than bottom, with NO cold spots.

These cars have VERY LITTLE excess cooling capacity designed in, so the slightest variation will cause the temp to climb "abnormally". Make sure your timing is set right. Make sure your heat riser is working, or, better yet, wire it wide open.

Joe

[Don H.]

Re: C2 Cooling Issues

Bruce,

I agree with all the above and would check all the basics. Since you just purchased it, you can't be sure of anything. I presently have my third 64/65 300hp with air and your temp will run in the range you describe.

Don H.

[Craig S.]

Re: C2 Cooling Issues

Bruce - like everyone else suggests, check all the other factors first. My 67 has a GM service dated aluminum harrison with a 72 date. No leaks, but it runs hot even with the air off....hard to keep it down around 180. When I turn the air on, it climbs like yours....and will not stabilize very well at all. It has definitely been above the 210 you mention...Craig

[Les Jacobs]

Re: C2 Cooling Issues

Hey Bruce I was in the same boat this summer. Bought a 63 and it seemed to be running so hot I got scared. I found that the temp gauge was out of calibration, and was actually running cooler than I thought. (I relied on a variety of home devised tests and cobbled up devices to come to that conclusion). But since I still didn't trust my results, I bought a remote IR thermometer (about70- 130$) and used it to measure the temp of the engine under a variety of conditions. Bottom line the engine was running at 180 despite the gauge reading of 220 and up. I think its a great tool for the car and use it around the house as well, and I encourage you to consider getting one. Good Luck Les

[Gary S.]

Re: C2 Cooling Issues

If you find that you have an original radiator then you are doing quite well to see only 210 degrees. My 66 had the original radiator and it was great around town. Hit the freeways and the temp would start going north rather quickly. I followed all of the good advice that is posted here about timing, hoses, etc. In the end, a new DeWitts radiator gave me my highway cruising back.

Gary

[Thomas D.]

Re: C2 Cooling Issues

Bruce, (and others) don't forget we offer the original radiator in a "no frills" version for $695. It's the same 3155316 without the dating, painting, ink stamp, foil sticker, and drain valve. We do this to compete with all the other aftermarket aluminum radiator companies that sell their rads bare. In some cases, it is cheaper than buying the wrong radiator.