67 Overheating Need help PLEASE
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Heel & Toe
Joined: Apr 2007
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67 Overheating Need help PLEASE
My dad has 1967 Vette 327 4 speed, power nothing. The motor was rebuilt to stock specs in 2007. It ran fine with the original radiator... temp would slowly climb in traffic then immediately go back down upon the car moving. In AUG we replaced the radiator with a brass replacement from ecklers which cost under 400 bucks. It has been overheating (at idle, under power,) since then which leads me to believe the radiator is garbage. When I say overheating i mean blowing antifreeze from overflow. Just looking for some ideas/advise from those who have experienced this issue before, and what was done to fix problem. Do i need to buy him a 800-900 aluminum replacement
thanks
JR
thanks
JR
Burning Brakes
Joined: Mar 2008
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From: Magnolia Texas
Give us a little more info... new thermostat? Good (new) hoses? Antifreeze? What pressure cap are you running? Did you do anything else to the car before this started?
There's really no reason why a (quality) replacement brass radiator shouldn't do the job although the DeWitts would have given you a bit more cooling capacity.
Steve
There's really no reason why a (quality) replacement brass radiator shouldn't do the job although the DeWitts would have given you a bit more cooling capacity.
Steve
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Go with a Dewitt's aluminum radiator. The copper/ brass radiators just don't do the job when ambient temps get over 70 degrees. Make sure your clutch fan is in good operating order.
Le Mans Master
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From: PERCUSSIVE MAINTENANCE: The art of whacking the crap out of an electronic device to get it to work.
A new copper radiator should work just fine in your car. Copper worked very well when these cars were built. You need to look elsewhere................Thermostat, fan clutch, timing and vacuum advance, and fan shroud and insulation.
Former Vendor
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From: Brighton
No you don't but you should stay with an aluminum radiator because that's what came with the car. You have three (3) options for you car, here are the heat rejection rates.
Copper/brass 3290btu/min $400
Replacement aluminum 4100/btu/min $525
Restoration aluminum 4600/btu/min $875
With the copper replacements 30% less capacity than the original it baffles me how anyone could say they "should be fine". I don't understand why dealers continue to even offer them.
If you are on a budget and need a good replacement this is the way to go. Our Direct Fit (A63M) is a nice looking radiator with similar performance (10% reduction) to the stock radiator.
Copper/brass 3290btu/min $400
Replacement aluminum 4100/btu/min $525
Restoration aluminum 4600/btu/min $875
With the copper replacements 30% less capacity than the original it baffles me how anyone could say they "should be fine". I don't understand why dealers continue to even offer them.
If you are on a budget and need a good replacement this is the way to go. Our Direct Fit (A63M) is a nice looking radiator with similar performance (10% reduction) to the stock radiator.
Last edited by Tom@Dewitt; Oct 9, 2011 at 09:17 AM.
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Le Mans Master
Joined: Oct 2000
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From: PERCUSSIVE MAINTENANCE: The art of whacking the crap out of an electronic device to get it to work.
No you don't but you should stay with an aluminum radiator because that's what came with the car. You have three (3) options for you car, here are the heat rejection rates.
Copper/brass 3290btu/min $400
Replacement aluminum 4100/btu/min $525
Restoration aluminum 4600/btu/min $875
With the copper replacements 30% less capacity than the original it baffles me how anyone could say they "should be fine". I don't understand why dealers continue to even offer them.
If you are on a budget and need a good replacement this is the way to go. Our Direct Fit (A63M) is a nice looking radiator with similar performance (10% reduction) to the stock radiator.
Copper/brass 3290btu/min $400
Replacement aluminum 4100/btu/min $525
Restoration aluminum 4600/btu/min $875
With the copper replacements 30% less capacity than the original it baffles me how anyone could say they "should be fine". I don't understand why dealers continue to even offer them.
If you are on a budget and need a good replacement this is the way to go. Our Direct Fit (A63M) is a nice looking radiator with similar performance (10% reduction) to the stock radiator.
Race Director
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with this. Get an infrared tester and get the right temp readings before you go spending tons of money! Take reading at lots of places on the motor (block) and rad. I hope the block was cleaned out well before being assembled, otherwise sediment and rust could be the problem. Good luck!
Le Mans Master
Joined: Jul 2000
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Of course go thru all the basics of mechanical aspects that influence cooling....I did and ended up replacing the original rad with a DeWitts reproduction aluminum done to NCRS specs anyway. Worked great and did the trick.....
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Army
Le Mans Master
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From: PERCUSSIVE MAINTENANCE: The art of whacking the crap out of an electronic device to get it to work.
Because he said this about me "it baffles me how anyone could say they "should be fine". Copper radiators do work just fine but only if the rest of the cooling system is OK. That was my point. Check the rest of the system before spending money on another radiator that my not be the problem.
Team Owner
Joined: Mar 2003
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From: Greenville, Indiana
Because he said this about me "it baffles me how anyone could say they "should be fine". Copper radiators do work just fine but only if the rest of the cooling system is OK. That was my point. Check the rest of the system before spending money on another radiator that my not be the problem.
Is that fine? Well, it is for me considering the money I saved. It hasn't ever boiled over or gotten any hotter than 205*. Also, when the temperature gets in the '90's, I don't consider it a pleasant experience to be driving around in a non-air coupe anyway.
Some people have to see the temp gauge on 180* max or they panic!
On the other hand, a new replacement aluminum radiator from DeWitt's isn't a bad idea.
Last edited by MikeM; Oct 9, 2011 at 11:54 AM.
Burning Brakes
Joined: Jun 2006
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From: Hudson North Carolina
You say it is overheating because it is puking. What is the temp gauge reading? Only fill the expansion tank about 1/2 full after it burps any more and any system with any radiator will puke. A 30 % reduction in cooling is quite a bit and I agree with Tom they shouldn't be offered without at least disclosing that fact. How are the seals around the radiator?
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From: Greenville, Indiana
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Assuming everything else is set up properly ie: clutch fan, radiator seals, timing and vacuum advance you will benefit from an aluminum radiator. Tom knows of what he speaks. I would much rather run 180 than 205-210.
Team Owner
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From: Washington Michigan
1. Cap isn't holding rated pressure (15 psi), reducing boiling point.
2. Expansion tank is over-filled, expanding coolant has nowhere to go except out of the overflow (it should only be 1/2-full, cold).
3. Coolant won't boil until 265*F with the correct 50-50 mix of anti-freeze/water and the correct 15 psi cap; what does the temp gauge show when it pukes, and what does an I.R. gun "shot" of the upper radiator hose just above the thermostat housing show when that occurs, and how does the I.R. gun reading compare with the temp gauge reading at the same time?
Do you have the correct fan, clutch, and shroud? Everything in the cooling system better be in top shape if you have a copper/brass radiator. Read this if you're not familiar with how a Corvette cooling system works:
http://www.lbfun.com/warehouse/tech_...em/cooling.pdf
Former Vendor
Joined: Jan 2000
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From: Brighton
When someone posts the car is "overheating" I assume they mean temperature and not expanding out due to being over filled. There are way to many previous threads in the history to ask all the obvious questions.
Zee, you have to understand that GM designed all midyear small block cars with the same 4600btu rated heat exchanger, that included a 250HP base motor and a 365HP FI car. Some cars generate less heat than others due to tons of variables, most of the variable modifications (IE overbores, stokers, special cams, trick stuff, tuning and timing). Then throw in different climate areas where one guy has 80 degree summers and the next has 110 degree days.
Everyones engine is different these days and the perception of "fine" is as well. This year at Carlisle someone said his copper radiator works fine as long as he didn't drive it when it was over 80 outside. Too me, that's not fine. Then you have the guy where the copper unit does the job and maintains the engine temps below 200, which is great. It doesn't change the fact his radiator is 2/3 the rating of the original. For him, 2/3 is enough and he might conclude that all this stuff about aluminum is just propaganda.
Le Mans Master
Joined: Oct 2000
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From: PERCUSSIVE MAINTENANCE: The art of whacking the crap out of an electronic device to get it to work.
Absolutely, assuming it is over heating.
When someone posts the car is "overheating" I assume they mean temperature and not expanding out due to being over filled. There are way to many previous threads in the history to ask all the obvious questions.
Zee, you have to understand that GM designed all midyear small block cars with the same 4600btu rated heat exchanger, that included a 250HP base motor and a 365HP FI car. Some cars generate less heat than others due to tons of variables, most of the variable modifications (IE overbores, stokers, special cams, trick stuff, tuning and timing). Then throw in different climate areas where one guy has 80 degree summers and the next has 110 degree days.
Everyones engine is different these days and the perception of "fine" is as well. This year at Carlisle someone said his copper radiator works fine as long as he didn't drive it when it was over 80 outside. Too me, that's not fine. Then you have the guy where the copper unit does the job and maintains the engine temps below 200, which is great. It doesn't change the fact his radiator is 2/3 the rating of the original. For him, 2/3 is enough and he might conclude that all this stuff about aluminum is just propaganda.
When someone posts the car is "overheating" I assume they mean temperature and not expanding out due to being over filled. There are way to many previous threads in the history to ask all the obvious questions.
Zee, you have to understand that GM designed all midyear small block cars with the same 4600btu rated heat exchanger, that included a 250HP base motor and a 365HP FI car. Some cars generate less heat than others due to tons of variables, most of the variable modifications (IE overbores, stokers, special cams, trick stuff, tuning and timing). Then throw in different climate areas where one guy has 80 degree summers and the next has 110 degree days.
Everyones engine is different these days and the perception of "fine" is as well. This year at Carlisle someone said his copper radiator works fine as long as he didn't drive it when it was over 80 outside. Too me, that's not fine. Then you have the guy where the copper unit does the job and maintains the engine temps below 200, which is great. It doesn't change the fact his radiator is 2/3 the rating of the original. For him, 2/3 is enough and he might conclude that all this stuff about aluminum is just propaganda.