Overheating in a 76
Thread Starter
Heel & Toe
Joined: Jul 2006
Posts: 18
Likes: 0
Overheating in a 76
I have a 76 vette with two electric fans and a clutch mounted on the front. So why do I have an overheating issue after driving 20 min below or at 200 on the water temp? I have talked to several people and need to probably pull the hose and check the thermostat. I just thought I would get a few more thoughts.
Thanks!
Thanks!
Drifting
Joined: Jun 2005
Posts: 1,950
Likes: 498
From: Chino Hills CA
with your engine hot and idling, with the fans going, open your hood about 4 inches. You should feel the hot air just blowin' out the opening. If not, your fans aren't pulling enough, if so, your radiator or thermostat isn't doing it's job. Pull the thermostat out and see if it makes a difference. With the engine cold, start her up with the radiator cap off. You should see some serious movement of coolant, especially when you rev it. If not, you need a new water pump. My small block with just a flex fan, no clutch, with a stock copper re-cored radiator never gets even near 200 degrees. I do have the open L88 scoop which really evacuates the heat though.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Pro
Joined: Mar 2006
Posts: 724
Likes: 1
From: NY
St. Jude Donor '06
Originally Posted by Vroomvroom
On the freeway it seems to stay under 200. If I go to idle after driving for 10-15 min on the freeway then it starts to spike. If I am driving around town it will gradually start to overheat.
Thread Starter
Heel & Toe
Joined: Jul 2006
Posts: 18
Likes: 0
its a 350 rebuilt with what looks like a fairly recent replaced radiator. I am wondering if it has a thermostat on it and if that is the reason it isn't cooling well. I am going to pull the hose off in the next couple of days to check. I have already checked the local auto stores for a replacement. I really don't want to replace the radiator just yet.
I have heard different opinions about thermostat vs no thermostat and the response to cooling the engine. Some say it is necessary to cool the engine properly. Others say it shouldn't matter and that the problem lies somewhere else. The only thing it leaks is tranny fluid. I have tightened the pan but it still drips. I am looking for a replacement gasket as a backup. Looking to try tightening once more before I do.
I have heard different opinions about thermostat vs no thermostat and the response to cooling the engine. Some say it is necessary to cool the engine properly. Others say it shouldn't matter and that the problem lies somewhere else. The only thing it leaks is tranny fluid. I have tightened the pan but it still drips. I am looking for a replacement gasket as a backup. Looking to try tightening once more before I do.
Pro
Joined: Mar 2006
Posts: 724
Likes: 1
From: NY
St. Jude Donor '06
You might want to check to see if there is any air in the system. I know cars overheat from that. With 2 fans and a good radiator, you should have no overheating problems. Check for air and any blockages in the system. Check the hose to see if it is collapsing. Also, take th radiator cap off and see how the flow is. If there is a thermostat, when it opens you should see water levelgo down and circulation.
Burning Brakes
Joined: Nov 2005
Posts: 832
Likes: 1
From: Breckenridge Colorado
Originally Posted by bextreme1
What engine do you have?? Mine does the exact opposite. Around 200 on highway after about 1/2 hr. at over 70 but then when I slow down it cools down fairly quickly to 180. I have a 350 rebuilt to 330HP and only the stock radiator, although it's a new one.
Without the seals the air will flow right past the radiator at the higher speeds and will not flow through it to keep it cool. I will be installing them tonight but I fully expect this to be what will bring down my temps at the higher cruising speeds. Important to make sure the lower air dam is also intact and working properly.
Burning Brakes
Joined: Nov 2005
Posts: 832
Likes: 1
From: Breckenridge Colorado
Originally Posted by rihwoods
I run 200-205 in 110 F weather highway...195-197 or so traffic with just a clutch fan..
Poor poor you
It gets up to 110F where you are at? Holy Crap!!!! I think I would burst into flames if I came out there. I cannot even visit my relatives in Charleston SC in the summertime because it is too hot for me. It was 40 when I woke up this morning 
Race Director
Joined: Feb 2005
Posts: 16,100
Likes: 17
Originally Posted by MartyW
Poor poor you It gets up to 110F where you are at? Holy Crap!!!! I think I would burst into flames if I came out there. I cannot even visit my relatives in Charleston SC in the summertime because it is too hot for me. It was 40 when I woke up this morning
It gets up to 110F where you are at? Holy Crap!!!! I think I would burst into flames if I came out there. I cannot even visit my relatives in Charleston SC in the summertime because it is too hot for me. It was 40 when I woke up this morning ...cool today..only 95...
Last edited by rihwoods; Jul 26, 2006 at 02:00 PM.
Burning Brakes
Joined: Nov 2005
Posts: 832
Likes: 1
From: Breckenridge Colorado
Thats true about the humidity. The humidity in Charleston SC is usually like 90-%100. At least where I am at we get about %20 humidity and it is always cool You should get a chance some year to attend the 'Vettes On The Rockies' event which is this week. Would be a good chance to get out of the heat for a week in the summer.
You should get a chance some year to attend the 'Vettes On The Rockies' event which is this week. Would be a good chance to get out of the heat for a week in the summer.
Drifting
Joined: Sep 2004
Posts: 1,532
Likes: 4
From: Fairview Heights Illinois, near Saint Louis MO, STL C3 Shark
Originally Posted by bextreme1
What engine do you have?? Mine does the exact opposite. Around 200 on highway after about 1/2 hr. at over 70 but then when I slow down it cools down fairly quickly to 180. I have a 350 rebuilt to 330HP and only the stock radiator, although it's a new one.
