It wouldn't surprise me if it becomes a new radiator at some point.
only overheats when A/C is on?!?! why?
Thread Starter
Race Director
Joined: Nov 2000
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From: stop the fun suckers
update:
I hit it with the laser and noted the following:
20* temp difference between the upper and lower radiator hose...however, what was very interesting was that I had a 30* difference between the top fins of the radiator and those at the bottom.. I'm thinking this is pointing to a bum radiator.. damit.. I just had it rodded.. oh and I checked my rcipts.. it was rodded in 2002 (so four years ago).. I've heard that they can only be rodded once and then its time for a new one.. is there an alternate solution? maybe a powerflush?!??!
I hit it with the laser and noted the following:
20* temp difference between the upper and lower radiator hose...however, what was very interesting was that I had a 30* difference between the top fins of the radiator and those at the bottom.. I'm thinking this is pointing to a bum radiator.. damit.. I just had it rodded.. oh and I checked my rcipts.. it was rodded in 2002 (so four years ago).. I've heard that they can only be rodded once and then its time for a new one.. is there an alternate solution? maybe a powerflush?!??!
Melting Slicks
Joined: Jul 2006
Posts: 3,356
Likes: 1
From: Chesapeake Va
Originally Posted by 383_BluByU
update:
I hit it with the laser and noted the following:
20* temp difference between the upper and lower radiator hose...however, what was very interesting was that I had a 30* difference between the top fins of the radiator and those at the bottom.. I'm thinking this is pointing to a bum radiator.. damit.. I just had it rodded.. oh and I checked my rcipts.. it was rodded in 2002 (so four years ago).. I've heard that they can only be rodded once and then its time for a new one.. is there an alternate solution? maybe a powerflush?!??!
I hit it with the laser and noted the following:
20* temp difference between the upper and lower radiator hose...however, what was very interesting was that I had a 30* difference between the top fins of the radiator and those at the bottom.. I'm thinking this is pointing to a bum radiator.. damit.. I just had it rodded.. oh and I checked my rcipts.. it was rodded in 2002 (so four years ago).. I've heard that they can only be rodded once and then its time for a new one.. is there an alternate solution? maybe a powerflush?!??!
PS when you check the in and out temps, dont shoot the hoses ,shoot the tanks right by the hoses. The rubber of the hoses seems to insulate and skew the readings. BTW 4 years ago is not "just having it rodded".
Team Owner
Joined: Jun 2005
Posts: 46,295
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From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
Originally Posted by 383_BluByU
update:
I hit it with the laser and noted the following:
20* temp difference between the upper and lower radiator hose...however, what was very interesting was that I had a 30* difference between the top fins of the radiator and those at the bottom.. I'm thinking this is pointing to a bum radiator.. damit.. I just had it rodded.. oh and I checked my rcipts.. it was rodded in 2002 (so four years ago).. I've heard that they can only be rodded once and then its time for a new one.. is there an alternate solution? maybe a powerflush?!??!
I hit it with the laser and noted the following:
20* temp difference between the upper and lower radiator hose...however, what was very interesting was that I had a 30* difference between the top fins of the radiator and those at the bottom.. I'm thinking this is pointing to a bum radiator.. damit.. I just had it rodded.. oh and I checked my rcipts.. it was rodded in 2002 (so four years ago).. I've heard that they can only be rodded once and then its time for a new one.. is there an alternate solution? maybe a powerflush?!??!
Melting Slicks
Joined: Jul 2006
Posts: 3,356
Likes: 1
From: Chesapeake Va
Originally Posted by LT4CompYell
although he has a different thermostat, I know SJW just did a stock rad swapout. ask him what the difference(s) are, if any. so did jet-jock. both cars to my knowledge, however, are stock cars with only minor mods.
Team Owner
Joined: Jun 2005
Posts: 46,295
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From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
Originally Posted by edcmat-l1
Mods and t-stat aside, the temp drop across a rad is the indicator of the efficiency of the radiator. In other words, regardless of inlet temp (which is affected by mods, increase in CID, etc) the temp DROP should be the same. If one car has an inlet temp of 185 and another an inlet temp of 210 and the radiators are working at the same eff. (all tubes flowing, same amount of airflow) the overall temp of the system may differ but the temp DROP should be roughly the same. # wise the more DROP the better. But it shoud be in excess of 30*, preferably around 40*. Id bet money after he replaces that rad the drop is in the 40* range. Hope this helps
Drifting
Joined: May 2005
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From: Chicago Executive Airport, formerly known as Palwaukee
No-IL Events Coordinator
St. Jude Donor '12-'13-'14-'15-'16-'17
Originally Posted by TorchRedlt4man
on page 1 of this thread How old is the radiator? What type of construction?
Having the A/C on will bring the hot air that the condensor is giving off right through the radiator.
I believe there is a problem with the radiator.
Having the A/C on will bring the hot air that the condensor is giving off right through the radiator.
I believe there is a problem with the radiator.
NOT!
About two years ago I was experiencing hotter temperatures on hotter days. I asked my radiator man (who used to supply all my cooling system needs when I owned my auto & truck repair shop) what my problem could be. He asked me how old my radiator was. At the time it was 8 years old. He told me aluminum loses its ability to transfer heat after several years. I purchased a GM OEM radiator from him and VOILA!!! my cooling system temps immediately dropped to the original levels.
Last edited by TorchRedlt4man; Aug 26, 2006 at 08:55 PM.
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Melting Slicks
Joined: Jul 2006
Posts: 3,356
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From: Chesapeake Va
Originally Posted by TorchRedlt4man
He told me aluminum loses its ability to transfer heat after several years.
That sounds like
As long as its aluminum how can the heat dissapation change? I would think the composition of the metal would have to change. My exp. with this type problem is flow. And like what he found with the trusty temp gun (one of my favorite tools, lots of ways to diag problems, cooling system, brakes dragging, etc) its always the bottom of the rad that stops flowing. A good way to double check it is, after the rad is out of the car, put the upper hose on it so the hose is going up and quickly poor alot of ice water thru the radiator while the radiator is in an upright position. The rad will get real cold, obviously, and if the bottom doesnt, badda bing!
Melting Slicks
Joined: Jul 2006
Posts: 3,356
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From: Chesapeake Va
Originally Posted by edcmat-l1
Classic radiator flow problem. The best way to tell is to remove the fans so you can get to the back side of the rad. Run the car until it warms up to close to operating temp, then feel the radiator with your hand from top to bottom. Chances are you will find the lower part of the radiator to be considerably cooler than the top. if you have access to an infrared temp gun you can actually see the temp difference. Its always better to diagnose methodically than to guess and replace parts. Good luck!!
Drifting
Joined: May 2005
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From: Chicago Executive Airport, formerly known as Palwaukee
No-IL Events Coordinator
St. Jude Donor '12-'13-'14-'15-'16-'17
Originally Posted by edcmat-l1
That sounds like
As long as its aluminum how can the heat dissapation change? I would think the composition of the metal would have to change.
Pay very close attention to the sentence referring to 100 degrees centigrade. Translated to fahrenheit, 212 degrees. Most C4s run between 212 and 238 degrees constantly. Except for guys like myself who have their systems running between 170 and 190 degrees.
On the flip side (colder temperatures) aluminum retains its strength and works better. Doesn't help us too much. Not many of us running our cooling system at below freezing temps!
Last edited by TorchRedlt4man; Aug 28, 2006 at 07:15 PM.
Melting Slicks
Joined: Jul 2006
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From: Chesapeake Va
At high temps aluminum looses it STRENGTH. Not conductivity. They're 2 different things. If it lost conductivity I dont think it would be the most popular choice of material for radiators, heater cores, heat sinks (like the one behind the ICM) etc.you're using a misinterpretation to try to support a statement. Because alum looses strength does not equate to loosing CONDUCTIVITY.
Additionally, the article says NOTHING about any of aluminum's properties (strength, conductivity) CHANGING with age, or time.
statement. Because alum looses strength does not equate to loosing CONDUCTIVITY.Additionally, the article says NOTHING about any of aluminum's properties (strength, conductivity) CHANGING with age, or time.
Last edited by edcmat-l1; Aug 29, 2006 at 11:39 AM.
Drifting
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From: Chicago Executive Airport, formerly known as Palwaukee
No-IL Events Coordinator
St. Jude Donor '12-'13-'14-'15-'16-'17
My radiator man has had over 40 years of experience. Would you rather have a weak radiator that can still conduct heat?
All I know is what I saw with my own eyes. Which is more accurate than anything that is found on the net. After replacing my radiator, my temps returned to their normal ranges.
My Dexcool was in excellent condition. I flushed my system, but got no debris or rust out of it. The Dexcool I took out of it looked identical to the Dexcool I put into it.
My radiator lasted about 8 years. A lot longer than a lot of radiators in C4s. Maintaining the coolant properly and maintaining temperatures enabled this to occur.
Just because you do not agree with a statement, does not make that statement BS!
All I know is what I saw with my own eyes. Which is more accurate than anything that is found on the net. After replacing my radiator, my temps returned to their normal ranges.
My Dexcool was in excellent condition. I flushed my system, but got no debris or rust out of it. The Dexcool I took out of it looked identical to the Dexcool I put into it.
My radiator lasted about 8 years. A lot longer than a lot of radiators in C4s. Maintaining the coolant properly and maintaining temperatures enabled this to occur.
Just because you do not agree with a statement, does not make that statement BS!
Melting Slicks
Joined: Jul 2006
Posts: 3,356
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From: Chesapeake Va
Originally Posted by TorchRedlt4man
My radiator man has had over 40 years of experience. Would you rather have a weak radiator that can still conduct heat?
All metals become weaker with heat. Alum, steel, etc. I have 20+ years exp myself. I worked for a cadillac shop for years and have a great deal of exp with alum. core, plastic tank rads
Originally Posted by TorchRedlt4man
All I know is what I saw with my own eyes. Which is more accurate than anything that is found on the net. After replacing my radiator, my temps returned to their normal ranges.
Originally Posted by TorchRedlt4man
My Dexcool was in excellent condition. I flushed my system, but got no debris or rust out of it. The Dexcool I took out of it looked identical to the Dexcool I put into it.
Originally Posted by TorchRedlt4man
My radiator lasted about 8 years. A lot longer than a lot of radiators in C4s. Maintaining the coolant properly and maintaining temperatures enabled this to occur.
Originally Posted by TorchRedlt4man
Just because you do not agree with a statement, does not make that statement BS!
PS the MOST common problem with plastic tank radiators is tank failure. The second is probably o-ring failure. If the "strength" of the alum was a signifigant issue, why dont we see more core ruptures? Come to think of it I've never seen a core failure that wasnt caused by at least corrosion.
Melting Slicks
Joined: Jul 2006
Posts: 3,356
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From: Chesapeake Va
Originally Posted by TorchRedlt4man
[SIZE="2"][COLOR="DarkGreen"][B] Would you rather have a weak radiator that can still conduct heat?
Drifting
Joined: May 2005
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From: Chicago Executive Airport, formerly known as Palwaukee
No-IL Events Coordinator
St. Jude Donor '12-'13-'14-'15-'16-'17
In order to get excellent cooling out of the newer radiators, the manufacturers have gone to more fins and a less dense grade of aluminum. The fins enable a smaller core (ie. 1 row which is 1" wide in my Vette) to better dissipate the heat that is generated. The grade of aluminum costs less and contributes to the heat being dissipated faster. The radiator also weighs less which is important in a sports car like we drive.
The late model C4 radiators are excellent radiators and will cool our engines over and over again. But, and you must have realized this was coming: A C4 radiator does not last forever. After 8 years and over 70,000 miles (you read that right: 70,000 miles!) the fact that the aluminum is less dense and lighter contributes to a less than brand new composition. I spoke in person with my radiator man this morning. He explained again to me that the heat cycles and the age of the radiator contribute to a less than perfect environment for cooling.
In GM's eyes, if a component lasts for 3 years or 36,000 miles, they are very happy. My radiator lasted a lot longer!
BTW, I only use distilled water with any of my coolants. I realize there are some folks who have had problems with Dexcool. In my Vette, I have been very happy with the performance. I changed it once and then again when I installed the new radiator.
The late model C4 radiators are excellent radiators and will cool our engines over and over again. But, and you must have realized this was coming: A C4 radiator does not last forever. After 8 years and over 70,000 miles (you read that right: 70,000 miles!) the fact that the aluminum is less dense and lighter contributes to a less than brand new composition. I spoke in person with my radiator man this morning. He explained again to me that the heat cycles and the age of the radiator contribute to a less than perfect environment for cooling.
In GM's eyes, if a component lasts for 3 years or 36,000 miles, they are very happy. My radiator lasted a lot longer!
BTW, I only use distilled water with any of my coolants. I realize there are some folks who have had problems with Dexcool. In my Vette, I have been very happy with the performance. I changed it once and then again when I installed the new radiator.
Melting Slicks
Joined: Jul 2006
Posts: 3,356
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From: Chesapeake Va
Originally Posted by TorchRedlt4man
[SIZE="2"][COLOR="Red"][B]In order to get excellent cooling out of the newer radiators, the manufacturers have gone to more fins and a less dense grade of aluminum. The grade of aluminum costs less and contributes to the heat being dissipated faster.
the fact that the aluminum is less dense and lighter contributes to a less than brand new composition.
the fact that the aluminum is less dense and lighter contributes to a less than brand new composition.
Originally Posted by TorchRedlt4man
In GM's eyes, if a component lasts for 3 years or 36,000 miles, they are very happy. My radiator lasted a lot longer!
Originally Posted by TorchRedlt4man
BTW, I only use distilled water with any of my coolants.
PS Ive seen aluminum core radiator last alot longer. And like I said before, they usually have tank failures before any kind of core failures. 95% of the core failures Ive seen over the past 20+years, including 16 years in FLA, have been flow problems, and they've all been the bottom tubes. Havent seen it once. Havent seen it twice. Seen it multiple times and have tested with a temp gun to verify. Almost the exact scenario that 383bluebyu said he found several posts back.
Last edited by edcmat-l1; Aug 29, 2006 at 04:31 PM.
