overheating problem
Melting Slicks
Joined: Aug 2012
Posts: 3,487
Likes: 83
From: Titusville Florida
Thread Starter
Instructor
Joined: Nov 2007
Posts: 185
Likes: 0
My car did the same thing, temps just kept climbing as the speed increased.
Oil temps would also climb with speed, as in 250* to 260* and higher.
The water temps were right behind the oil temps trailing along. I fought this for a couple years installing 3 different fan setups, AFR tuning with a wide band tuner, timing in every configuration I could come up with, vacuum advance no vacuum advance, 3 different water pumps, 3 different radiators, modifications to the nose of the car for better air flow to radiator and the only thing that brought the temps down to a manageable level was the engine oil cooler.
When I look back at the thousands of dollars spent to try and keep the engine cool and compare it to an engine oil cooler that can be bought for around $250 I got to look at it as a lesson learned.
You obviously need to make sure that all the components in the cooling system are working correctly and verify the oil temps to make sure this is your issue. If the water temps would be higher than the oil temps than I would say you don't have an oil temp issue.
I also spoke with a engineer at Hayden an he also told me to check the oil temps to see if they were the problem.
Now I'm running a 496 and I think the .060 over bore has allot to do with my temp issues.
I agree with Tom D. that each over heating issue is different from car to car but when I finally got mine fixed were I could drive the car and enjoy it I was at the end of my rope on trying to figure out what was causing the problem so when another forum member recommended installing an engine oil cooler (after verifying high oil temps) I was open for just about anything.
Today it doesn't matter what the outside temps are my car stays at T-stat setting of 180* nor does it matter how hard I drive the car.
After reading all the cooling issue threads on the forum day in and day out it sure seems as if the C3 had a marginal cooling system from the factory.
Just offering up what worked for me after endless attempts to fix mine.
It sure is great to know you can take it out for a run and not need to worry about the engine temps.
Neal
Oil temps would also climb with speed, as in 250* to 260* and higher.
The water temps were right behind the oil temps trailing along. I fought this for a couple years installing 3 different fan setups, AFR tuning with a wide band tuner, timing in every configuration I could come up with, vacuum advance no vacuum advance, 3 different water pumps, 3 different radiators, modifications to the nose of the car for better air flow to radiator and the only thing that brought the temps down to a manageable level was the engine oil cooler.
When I look back at the thousands of dollars spent to try and keep the engine cool and compare it to an engine oil cooler that can be bought for around $250 I got to look at it as a lesson learned.
You obviously need to make sure that all the components in the cooling system are working correctly and verify the oil temps to make sure this is your issue. If the water temps would be higher than the oil temps than I would say you don't have an oil temp issue.
I also spoke with a engineer at Hayden an he also told me to check the oil temps to see if they were the problem.
Now I'm running a 496 and I think the .060 over bore has allot to do with my temp issues.
I agree with Tom D. that each over heating issue is different from car to car but when I finally got mine fixed were I could drive the car and enjoy it I was at the end of my rope on trying to figure out what was causing the problem so when another forum member recommended installing an engine oil cooler (after verifying high oil temps) I was open for just about anything.
Today it doesn't matter what the outside temps are my car stays at T-stat setting of 180* nor does it matter how hard I drive the car.
After reading all the cooling issue threads on the forum day in and day out it sure seems as if the C3 had a marginal cooling system from the factory.
Just offering up what worked for me after endless attempts to fix mine.
It sure is great to know you can take it out for a run and not need to worry about the engine temps.
Neal
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
The remote filter is mounted to the trans cross member.
I have side pipes so I ran the lines through the hole for the exhaust pipe.
the picture was taken with my phone, reason for poor quality.
If you have some time and want to see what I went through with the cooling issues read through this thread:
http://forums.corvetteforum.com/c3-t...ler-496-a.html
now near the middle of this thread I switched from a very low efficient oil cooler to the Fluidyne cooler that is pictured in this thread. Its not well documented in the thread but when I moved the cooler form the front of the car to the rear of the car I installed the Fluidyne cooler.
Neal
I have side pipes so I ran the lines through the hole for the exhaust pipe.
the picture was taken with my phone, reason for poor quality.
If you have some time and want to see what I went through with the cooling issues read through this thread:
http://forums.corvetteforum.com/c3-t...ler-496-a.html
now near the middle of this thread I switched from a very low efficient oil cooler to the Fluidyne cooler that is pictured in this thread. Its not well documented in the thread but when I moved the cooler form the front of the car to the rear of the car I installed the Fluidyne cooler.
Neal
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Melting Slicks
Joined: Sep 2011
Posts: 3,372
Likes: 215
From: Peoria Arizona
I test drove our '77 on the freeway today for a short distance - about 3 miles each way. Only the second time at steady speeds like that. The motor is pretty new (about 150 miles on it) so I know it might run a little warmer until it's broken in.
New temp sender and 180 thermostat when I put the new motor in. Stock type replacement radiator which was in the car when we purchased it last year - very clean inside and in like new condition visually. Stock type fan and clutch.
My temp gauge runs right at 200 / 210 always, until I get up to speed for a bit like I did today. Temps climb to about 220 / 230 and hold there - or at least they did for that distance.
I got out my IR gun after reading this post and took temps in several spots: upper and lower rad hoses (at both ends), thermostat housing, intake manifold, directly on the temp sending unit (drivers side head) etc. All of those temps are running 30 degrees (and more) cooler then the gauge is showing.
When I started testing, the gauge was reading it's normal 200 / 210 area. Thermostat housing shows 170 / 175, upper hose shows about the same, lower hose shows 115 / 130 depending on where I aim the gun etc.
Looks to me like this sending unit is way off. I'm wondering if that's that case with your car as well?
Also, I have foam seals on top of the radiator support (to hood), under the support across the top of radiator, and I just added another on the passenger side (down the side of the radiator). We'll see if that helps.
Adam
New temp sender and 180 thermostat when I put the new motor in. Stock type replacement radiator which was in the car when we purchased it last year - very clean inside and in like new condition visually. Stock type fan and clutch.
My temp gauge runs right at 200 / 210 always, until I get up to speed for a bit like I did today. Temps climb to about 220 / 230 and hold there - or at least they did for that distance.
I got out my IR gun after reading this post and took temps in several spots: upper and lower rad hoses (at both ends), thermostat housing, intake manifold, directly on the temp sending unit (drivers side head) etc. All of those temps are running 30 degrees (and more) cooler then the gauge is showing.
When I started testing, the gauge was reading it's normal 200 / 210 area. Thermostat housing shows 170 / 175, upper hose shows about the same, lower hose shows 115 / 130 depending on where I aim the gun etc.
Looks to me like this sending unit is way off. I'm wondering if that's that case with your car as well?
Also, I have foam seals on top of the radiator support (to hood), under the support across the top of radiator, and I just added another on the passenger side (down the side of the radiator). We'll see if that helps.
Adam
Thread Starter
Instructor
Joined: Nov 2007
Posts: 185
Likes: 0
I am not sure about the others in the thread but when I tested mine they were right about where the gauge read. I have a new motor but the original temp sender. The new ones can be off like yours reads. I think it has something to do with the resistance they are set for if I understood what I read correctly
Melting Slicks
Joined: Aug 2012
Posts: 3,487
Likes: 83
From: Titusville Florida
I am not sure about the others in the thread but when I tested mine they were right about where the gauge read. I have a new motor but the original temp sender. The new ones can be off like yours reads. I think it has something to do with the resistance they are set for if I understood what I read correctly
)...
Melting Slicks
Joined: Aug 2012
Posts: 3,487
Likes: 83
From: Titusville Florida
Sorry, was just having a little light hearted moment with the OP of the thread and we are the ones after all whom are dealing with our Vettes getting a little warmer than we are comfortable with.
Didn't mean to offend anyone
Didn't mean to offend anyone