1962 Engine Temperature

[wjw1741]

I have 327 engine that was rebuilt, and when doing so, they had to bore it out to sixty over. My question is this: A few weeks ago after having it rebuilt the engine temp was always right around 180 - 210. Well, last week I had a radiator problem, from what I have been told, the weld around the drain plug broke. So, out goes the radiator, gets welded and now its back in, however the temperature is now running at 210 - 240. At what temperature should it operate at? Is there an additive that I can put in it to cool (like wetter water or something)? At what temperature should I become concerned with? I have always heard that these cars tend to run hot. The radiator is only three years old, but only used for two summers. If I remember correctly, it came from Corvette Central. Does anyone know what would cause the drain plug weld to just break? Is there maybe some underlying problem that someone is missing.

Thanks in advance for your help. This is a great resource and everyone is very knowledgable.

Warren

 

[JohnZ]

1. Is the radiator aluminum, or copper/brass? Do you know the brand name or who made it? Can you post a photo of it?

2. These cars "run hot" usually because the temperature gauges are wildly inaccurate, especially if the sending unit has been replaced. Have you verified the temp gauge accuracy with an I.R. gun "shot" of the upper radiator hose just above the thermostat housing vs. the gauge reading at the same time so you know what the gauge is really telling you? Step #1 in diagnosing a cooling problem is to determine if you really have a problem.

3. Do you have the correct fan, clutch, and shroud installed?

It should run at 180*-190* if the cooling system is functioning properly. We need the answers to the above questions to help you diagnose the issue.

 

[wjw1741]

The radiator is copper/brass. I do not know the name brand, but may be able to post a picture later this afternoon.

I can tell you with almost 100% certainity that the installer did not use a IR gun and take a reading. I can tell you that the original temp gauge does not work, even after placing a new sending unit. I had to install an aftermarket seperate gauge for insurance purposes. So the gauge is brand new.

And as far as I can tell, the correct fan, clutch and shroud are original and installed. My only problem is this: When I got the car on the road, the original fan was not installed, but it was the original engine. Now, my father did all the work on the car before, however he as passed away and I cannot ask him if there was a reason that he took the original fan off and put on a different one. Is there a way to tell if the fan clutch is not working properly?

 

[JohnZ]

The copper/brass replacement radiator has significantly less cooling capacity than the original stacked-plate Harrison aluminum radiator; it's a radiator for a 265/283, trying to cool a 327.

It's essential to take an I.R. gun shot of the upper radiator hose and compare that to the gauge reading at the same time; replacement sending units are notoriously inaccurate (read high).

Need a photo of the fan and clutch to see what you have installed.

 

[wjw1741]

You know its funny you mention the fan clutch. Is there a way to tell if that is working properly? I am beginning to feel that there had to be more of a reason for my father to have removed the original fan to begin with. He was never a person to do something unless something was broken. I have been given some advice....remove the thremostat all together, and perhaps buy a new clutch.

I drove the car Friday night and after arriving at my destination I could hear the antifreeze crackling and or boiling in the radiator. Nothing spilled out or boiled over, but I could hear it, and it sounded hot.

I will try to get some pictures of the engine today...the car is with me this morning.

 

[wjw1741]

I have put up some pictures on my profile page. Was not sure how to put them into the post, but I have some radiator and fan pics under the rebuilt engine album. Hope it helps. Where should I pick up a new fan clutch for the car?

 

[JohnZ]

Do NOT remove the thermostat - that's bad advice; if anything, replace it with a 180* thermostat - if it's old, it may be sticking and not opening fully.

From the photos, the fan blade is about 2" rearward of where it belongs - it should be half-in and half-out of the rear edge of the shroud, as originally designed, for peak idle and low-speed traffic cooling efficiency. That may be due to the fan clutch - it takes GM #3916141, available from Paragon for about $125.

The copper/brass replacement radiator isn't helping you any either - it has significantly less cooling capacity than the correct stacked-plate Harrison aluminum radiator, which is available from Tom Dewitt (www.dewitts.com).

Still need to know how your temp gauge reading compares to an I.R. gun shot of the upper radiator hose at the same time.

 

[wjw1741]

You said the radiator is not helping. I was under the impression it was the same as the old one. It sure looks the same. What does stacked mean? I am a little ticked off because I never would have bought this one. I am getting a new fan clutch and will keep the thermastat in it is new. I am going to assume that a clutch from NAPA will not be good enough?

 

[JohnZ]

You said the radiator is not helping. I was under the impression it was the same as the old one. It sure looks the same. What does stacked mean? I am a little ticked off because I never would have bought this one. I am getting a new fan clutch and will keep the thermastat in it is new. I am going to assume that a clutch from NAPA will not be good enough?

You stated earlier that the replacement radiator was copper/brass (as all the low-cost parts-store replacements are); the original was aluminum, and had far more cooling capacity - and they're expensive (but worth it).

It's likely that any fan clutch you get at an auto parts store will not be thermostatically-controlled; the original was, and that's why you want the GM #3916141, made by Eaton.

 

[wjw1741]

I ordered a new fan clutch from Corvette Central. They claim it is the original GM part. I went to NAPA the other day, they had one at a fraction of the cost, but it was much larger than the one that is in there.

Here is a new question. Is there a way that I can get the original radiator fixed so that I can use that one again? I saved it with the hope of being able to do that, and would that be cheaper than an alluminum replacement?

I did not think it was alluminum since it was black. I associate alluminum with being silver. Anyway, had I known that, I would have certainly paid more for the replacement.

 

[wallyknoch]

I see your new here and a bit of advice to you is that anything that 'JohnZ' recommends is about the best advice you can get regarding your Vette on this or any other Vette forum. Your original should be aluminum. A 61 was unpainted bare aluminum however but black was the OE standard color for all 62`s.

Answering your question on rebuilding your original radiator, Its DEAD, hang it on the wall with other accumulated trophies............