Running Warm
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Joined: Feb 2005
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From: Santa Monica California
Running Warm
Hey gearheads! I took a trip from LA to San Diego early today when it was pretty cool out, low 60s. During stretches where there was almost no freeway traffic I was able to run at 90-95 MPH for 15-30 minutes. As I did this my water temp gauge went from usual temp of about 185-200 to 220-225 which is too warm especially given the cool weather. When I slowed down to 65-75 the temp went back to normal. No apparent leaks, coolant resevoir has normal level. Any ideas as to the problem and possible fix?
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
I'm not sure you have a problem. Running at the speeds you were will increase operating temps. If it continues to run at normal temps with normal driving, I wouldn't worry about it. Others may have a different view.
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
Originally Posted by jpw73vert
Hey gearheads! I took a trip from LA to San Diego early today when it was pretty cool out, low 60s. During stretches where there was almost no freeway traffic I was able to run at 90-95 MPH for 15-30 minutes. As I did this my water temp gauge went from usual temp of about 185-200 to 220-225 which is too warm especially given the cool weather. When I slowed down to 65-75 the temp went back to normal. No apparent leaks, coolant resevoir has normal level. Any ideas as to the problem and possible fix?
Racer
Joined: Mar 2006
Posts: 366
Likes: 1
From: Houston Texas
I agree with the others that you do not have a problem. The car warmed up under a load, then cooled back down to the starting point when the load was removed.
My gauge reads too high above 190, and too low below 175. I've seen 235 indicated (needle to the right of the second zero) while sitting in Houston summer traffic in air temps 100+ without boilover, vapor lock or other operating problem related to excessive heat. I've shot the engine with an IR gun and see 20 degrees variation depending on where I shoot.
I have had to accept that the indicated value on my gauge is not absolutely accurate but the needle movement lets me know things are working like they are supposed to (it is pretty cool to see the thermostat open up a few minutes after startup).
Besides, I also noticed that the other cars that live at my house only have a C for low scale and an H for full scale on their temp gauges - no actual temperature measurements or other indications. I've wondered if the vette gauge wasn't marked with 200 in the center if I would have really cared what the absolute temperature was as long as the needle stayed below the danger zone ...
My gauge reads too high above 190, and too low below 175. I've seen 235 indicated (needle to the right of the second zero) while sitting in Houston summer traffic in air temps 100+ without boilover, vapor lock or other operating problem related to excessive heat. I've shot the engine with an IR gun and see 20 degrees variation depending on where I shoot.
I have had to accept that the indicated value on my gauge is not absolutely accurate but the needle movement lets me know things are working like they are supposed to (it is pretty cool to see the thermostat open up a few minutes after startup).
Besides, I also noticed that the other cars that live at my house only have a C for low scale and an H for full scale on their temp gauges - no actual temperature measurements or other indications. I've wondered if the vette gauge wasn't marked with 200 in the center if I would have really cared what the absolute temperature was as long as the needle stayed below the danger zone ...
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
Originally Posted by justanotherdoe
I agree with the others that you do not have a problem. The car warmed up under a load, then cooled back down to the starting point when the load was removed.
My gauge reads too high above 190, and too low below 175. I've seen 235 indicated (needle to the right of the second zero) while sitting in Houston summer traffic in air temps 100+ without boilover, vapor lock or other operating problem related to excessive heat. I've shot the engine with an IR gun and see 20 degrees variation depending on where I shoot.
I have had to accept that the indicated value on my gauge is not absolutely accurate but the needle movement lets me know things are working like they are supposed to (it is pretty cool to see the thermostat open up a few minutes after startup).
Besides, I also noticed that the other cars that live at my house only have a C for low scale and an H for full scale on their temp gauges - no actual temperature measurements or other indications. I've wondered if the vette gauge wasn't marked with 200 in the center if I would have really cared what the absolute temperature was as long as the needle stayed below the danger zone ...
My gauge reads too high above 190, and too low below 175. I've seen 235 indicated (needle to the right of the second zero) while sitting in Houston summer traffic in air temps 100+ without boilover, vapor lock or other operating problem related to excessive heat. I've shot the engine with an IR gun and see 20 degrees variation depending on where I shoot.
I have had to accept that the indicated value on my gauge is not absolutely accurate but the needle movement lets me know things are working like they are supposed to (it is pretty cool to see the thermostat open up a few minutes after startup).
Besides, I also noticed that the other cars that live at my house only have a C for low scale and an H for full scale on their temp gauges - no actual temperature measurements or other indications. I've wondered if the vette gauge wasn't marked with 200 in the center if I would have really cared what the absolute temperature was as long as the needle stayed below the danger zone ...
Safety Car
Joined: Dec 2004
Posts: 4,876
Likes: 1
From: Jersey Shore Exit 98
I put a 180 stat in and the car still ran at 210* to 220* I tried that radiator additive 40* Below from Ecklers and I run at 200* all the time the stuff works. I purchased a bunch of it & use it in three of my cars. I have two pints left it sells for $24.99 plus shipping. if you want to try it give me what I paid $24.99 & I'll ship it free. Only have two left.
Oh another thing you could try is running straight antifreeze or coolant. Don't mix w/water. It takes longer for it to get hot and a few guys that race told me that's what they do.
Oh another thing you could try is running straight antifreeze or coolant. Don't mix w/water. It takes longer for it to get hot and a few guys that race told me that's what they do.
Last edited by Jims79; Nov 1, 2006 at 06:05 PM.
Safety Car
Joined: Sep 2005
Posts: 4,226
Likes: 643
From: Orange County Ca
Originally Posted by randyredleg
If it heats up at speed, it might be an airflow issue. Do you have front spoiler and radiator seals?
I had the same situation after painting but before putting the air dam back on. Now I don't run hotter even on a 90 deg day.
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Race Director
Joined: Feb 2006
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From: Inside the woods living my passion
St. Jude Donor '07-'08
My 82 coolant temp will stay under 200 @ sustained high speed runs, but my oil temps will rise 20 degrees or so rather than normal driving. so i would agree with the others It is Normal 
Last edited by C3Racing; Nov 1, 2006 at 09:50 PM.
Pro
Joined: Apr 2006
Posts: 647
Likes: 22
From: Norwalk CT and Boynton Beach FL
I have the same problem --- temp OK at 60-65 mph but above that it's running around 225 - 230 --- and that's without the A/C on, which no longer works.
I'm going to use a good radiator cleaner to flush out any crud, change the anitfreeze and add a spoiler extender which adds about
3 inches to the spoiler which should scoop up much more air and force it through the radiator. I think that will be a big help.
The big issue is that at 80 mph I'm doing 4000 rpm which is no good for the engine and generates too much heat. The best solution would be a new automatic transmission with 4 forward speeds instead of the stock three I've currently got.
I'm going to use a good radiator cleaner to flush out any crud, change the anitfreeze and add a spoiler extender which adds about
3 inches to the spoiler which should scoop up much more air and force it through the radiator. I think that will be a big help.
The big issue is that at 80 mph I'm doing 4000 rpm which is no good for the engine and generates too much heat. The best solution would be a new automatic transmission with 4 forward speeds instead of the stock three I've currently got.
Thread Starter
Advanced
Joined: Feb 2005
Posts: 84
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From: Santa Monica California
I do have a front air dam. what are radiator seals?
It still seems too hot to me. I went through this in the summer and the needle was flirting with the red zone. OTOH, I run like 4K rpms at the speeds I'm talking about, and that is pretty high.
gonna try the Ecklers radiator cleaner Jims79 mentioned, and straight antifreeze.
It still seems too hot to me. I went through this in the summer and the needle was flirting with the red zone. OTOH, I run like 4K rpms at the speeds I'm talking about, and that is pretty high.
gonna try the Ecklers radiator cleaner Jims79 mentioned, and straight antifreeze.
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
Originally Posted by jpw73vert
I do have a front air dam. what are radiator seals?
It still seems too hot to me. I went through this in the summer and the needle was flirting with the red zone. OTOH, I run like 4K rpms at the speeds I'm talking about, and that is pretty high.
gonna try the Ecklers radiator cleaner Jims79 mentioned, and straight antifreeze.
It still seems too hot to me. I went through this in the summer and the needle was flirting with the red zone. OTOH, I run like 4K rpms at the speeds I'm talking about, and that is pretty high.
gonna try the Ecklers radiator cleaner Jims79 mentioned, and straight antifreeze.
As for Eckler's, I'd stay clear. I've had too many problems with them lately. You can get a good radiator cleaner from any auto parts store.
Safety Car
Joined: Dec 2004
Posts: 4,876
Likes: 1
From: Jersey Shore Exit 98
Originally Posted by Jud Chapin
You can buy the seals from most Vette vendors. They form a barrier between the hood and radiator so air is forced into the rad. Without them, you can have an overheating problem. As far as straight antifreeze, you should use a 50/50 mix (antifreeze/distilled water) for optimum cooling and overall performance.
As for Eckler's, I'd stay clear. I've had too many problems with them lately. You can get a good radiator cleaner from any auto parts store.
As for Eckler's, I'd stay clear. I've had too many problems with them lately. You can get a good radiator cleaner from any auto parts store.
As for the stuff I purchased from ecklers its not a cleaner but a radiator additive to be added to the coolant and help lower running temps 20* to 40* it called 40* Below and its sold in all auto stores and by all the vendors for $24.99 a pint. It worked for me I now run at 200* all the time before I would heat up in the summer to 230*
But a lot of guys don't believe in additives. That's ok. You can try a 160* or 180* stat and the straight antifreeze and see it that works for you. I when a step further w/the additive.
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
[QUOTE=Jims79] I used the 50/50 for 30 years and now I run straight 100* now I only run the 100* in my vette which ran hot in my daily driver and the wive's van I still run the 50/50
I'm not sure what you're saying here, Jim. Are you saying your Vette runs cooler with 100% antifreeze?
I'm not sure what you're saying here, Jim. Are you saying your Vette runs cooler with 100% antifreeze?
Thread Starter
Advanced
Joined: Feb 2005
Posts: 84
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From: Santa Monica California
I took the beast in this AM for a flush and coolant refill. They told me that the coolant is boiling over even though the car ins't overheating. What's that about? Thermostat and water pump have maybe 5K miles on them. The radiator is years old. BTW, I took the car to "Jiffy Lube" for the flush/refill so I'm not entirely sure about their opinions on the matter.
Jims79, if you're reading, I just dropped the check in the mail. Thanks.
Jims79, if you're reading, I just dropped the check in the mail. Thanks.
Melting Slicks
Joined: Feb 2006
Posts: 2,209
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From: Mo
my 69 has a 427 about 600hp,and in the KC heat it run 190-195 with the a/c on.I have an aluminum rad,electric fans,and 160 thremostat.The hottest it's ever been was in Houston this summer it run 205.
Safety Car
Joined: Dec 2004
Posts: 4,876
Likes: 1
From: Jersey Shore Exit 98
Originally Posted by jpw73vert
I took the beast in this AM for a flush and coolant refill. They told me that the coolant is boiling over even though the car ins't overheating. What's that about? Thermostat and water pump have maybe 5K miles on them. The radiator is years old. BTW, I took the car to "Jiffy Lube" for the flush/refill so I'm not entirely sure about their opinions on the matter.
Jims79, if you're reading, I just dropped the check in the mail. Thanks.
Jims79, if you're reading, I just dropped the check in the mail. Thanks.
You can also check your T-stat by pulling it into boiling water it should open. If it doesn't the stat is no good.
Now if all the parts are good and working you may have air in the system. You can jack the front of the vette up put it on jack stands and add anti-freeze at the highest level. You can squeez the top hose to burp the system while adding fluid. I don't think you radiator is at fault. But your fan-clutch maybe shot. I forget how to test the clutch maybe someone will add to this. If not I'll look back into my notes & get back to you.
Jim
Intermediate
Joined: Dec 2005
Posts: 40
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I had the same problem. Posted a thread on this site and followed the suggestions. New 195 degree thermostat and no change. Radiator flush and no change. Radiator recored and no change. New fan clutch and no change. Installed a 160 degree thermostat and temp dropped. Radiator began leaking later and took it back to shop. I was asked what temp therm I had installed? When I told him a 160 degree, he said that there was no way I should ever go below a 180 degree. One of the sections in the radiator had come loose and caused the leak. He repaired the radiator and sold me a 180 therm and I have been happy ever after...lol.
Drifting
Joined: Jun 2004
Posts: 1,881
Likes: 9
From: staten island ny
Originally Posted by Jims79
I put a 180 stat in and the car still ran at 210* to 220* I tried that radiator additive 40* Below from Ecklers and I run at 200* all the time the stuff works. I purchased a bunch of it & use it in three of my cars. I have two pints left it sells for $24.99 plus shipping. if you want to try it give me what I paid $24.99 & I'll ship it free. Only have two left.
Oh another thing you could try is running straight antifreeze or coolant. Don't mix w/water. It takes longer for it to get hot and a few guys that race told me that's what they do.
Oh another thing you could try is running straight antifreeze or coolant. Don't mix w/water. It takes longer for it to get hot and a few guys that race told me that's what they do.
ESU