overheating problem
Thread Starter
7th Gear
Joined: Jun 2015
Posts: 7
Likes: 0
overheating problem
I have 76 corvette put In a 350 runs great except overheats if drove a few miles. I have flushed the radiator, checked the water pump, it has a clutch fan but I added a electric fan and over flow. Anyone have any ideas? Please help
Thread Starter
7th Gear
Joined: Jun 2015
Posts: 7
Likes: 0
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,170
From: Hermosa
More details would help.
When does it over heat, at cruise or idling or both?
What thermostat are you running?
What radiator are you running?
How are you classifying overheating, getting above a certain temp or are we talking boiling over?
What has been done to the engine?
Where is your timing set?
Does it have the front air dam installed?
What electric fan are you using, dual or single and does it have a shroud?
When does it over heat, at cruise or idling or both?
What thermostat are you running?
What radiator are you running?
How are you classifying overheating, getting above a certain temp or are we talking boiling over?
What has been done to the engine?
Where is your timing set?
Does it have the front air dam installed?
What electric fan are you using, dual or single and does it have a shroud?
Thread Starter
7th Gear
Joined: Jun 2015
Posts: 7
Likes: 0
More details would help.
When does it over heat, at cruise or idling or both?
What thermostat are you running?
What radiator are you running?
How are you classifying overheating, getting above a certain temp or are we talking boiling over?
What has been done to the engine?
Where is your timing set?
Does it have the front air dam installed?
What electric fan are you using, dual or single and does it have a shroud?
When does it over heat, at cruise or idling or both?
What thermostat are you running?
What radiator are you running?
How are you classifying overheating, getting above a certain temp or are we talking boiling over?
What has been done to the engine?
Where is your timing set?
Does it have the front air dam installed?
What electric fan are you using, dual or single and does it have a shroud?
Last edited by JMurry1; Oct 28, 2015 at 04:37 PM.
Melting Slicks
Joined: Apr 2009
Posts: 2,632
Likes: 112
From: Great Plains Iowa
I suggest you take a pressure check and see if hydrocarbons are entering your cooling system from a leaking head gasket. Does the fan clutch drive the fan HARD or just barely. When fast idling it should blow a LOT of air and if it doesn't the fan clutch is likely failing. And the little 12" fan doesn't do diddly squat to help anything.
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Burning Brakes
Joined: Dec 2005
Posts: 992
Likes: 56
From: Baldwinsville, NY
Water and antifreeze with a 15 psi cap boils at about 260F.
Are you using a IR gun to check the temperatures.
If the new engine has Vortec, heads you have a temperature sending unit that is not calibrated to the gage in your car?
Your new motor might have a 195F thermostat.
Are you using a IR gun to check the temperatures.
If the new engine has Vortec, heads you have a temperature sending unit that is not calibrated to the gage in your car?
Your new motor might have a 195F thermostat.
Pro
Joined: Mar 2006
Posts: 527
Likes: 84
From: SW Ohio
As you can tell a bunch of us have been down this road.
Can you feel the stock fan pulling air through the radiator? Check your air flow.
Clutch fans can & do go bad, a stock 7 blade AC clutch fan movers a ton of air across the radiator.
Can you feel the stock fan pulling air through the radiator? Check your air flow.
Clutch fans can & do go bad, a stock 7 blade AC clutch fan movers a ton of air across the radiator.
Pro
Joined: Nov 2013
Posts: 730
Likes: 37
From: Catoosa Okla
Drifting
Joined: Jun 2012
Posts: 1,990
Likes: 183
From: Port St. Lucie Fl
based on you saying it overheats at idle and while driving, in order for this to happen at both of these situations, you have to have a closed thermostat, collapsing lower hose, clogged radiator (inside or outside) or the timing is wrong. If the clutch fan were bad it would cool while driving, and adding the efan would help at idle neither of these happen.
Check these problems before you buy parts it will save you money and hassle in the long run.
I have a 406 in my car with uncoated headers and it would still cool down while driving WITHOUT the seals around the radiator and hood.
Check these problems before you buy parts it will save you money and hassle in the long run.
I have a 406 in my car with uncoated headers and it would still cool down while driving WITHOUT the seals around the radiator and hood.
Thread Starter
7th Gear
Joined: Jun 2015
Posts: 7
Likes: 0
based on you saying it overheats at idle and while driving, in order for this to happen at both of these situations, you have to have a closed thermostat, collapsing lower hose, clogged radiator (inside or outside) or the timing is wrong. If the clutch fan were bad it would cool while driving, and adding the efan would help at idle neither of these happen.
Check these problems before you buy parts it will save you money and hassle in the long run.
I have a 406 in my car with uncoated headers and it would still cool down while driving WITHOUT the seals around the radiator and hood.
Check these problems before you buy parts it will save you money and hassle in the long run.
I have a 406 in my car with uncoated headers and it would still cool down while driving WITHOUT the seals around the radiator and hood.
Former Vendor
Joined: Jan 2000
Posts: 5,593
Likes: 631
From: Brighton
Water and antifreeze with a 15 psi cap boils at about 260F.
Are you using a IR gun to check the temperatures.
If the new engine has Vortec, heads you have a temperature sending unit that is not calibrated to the gage in your car?
Your new motor might have a 195F thermostat.
Are you using a IR gun to check the temperatures.
If the new engine has Vortec, heads you have a temperature sending unit that is not calibrated to the gage in your car?
Your new motor might have a 195F thermostat.
Best answer
Race Director
Joined: Mar 2003
Posts: 11,608
Likes: 778
From: Eustis ( Area 51 Bat Cave ) Fl
no you didn't...
Oddly the last thread about overheating the cat fixed it with a Champion radiator and new name brand fans...so that might be a sign one of the seven seals has broken....
yeah, one 12" wasn't gonna hack it in this threads case, I would want to be sure the gauge is correct and go from there....