My first rebuild
Thread Starter
Drifting
Joined: Aug 2012
Posts: 1,650
Likes: 2
From: Tulsa Oklahoma
The video you see is at about 1000rpm when I hit the throttle and it idles down to about 650, is when you see the gush coming out. While idling, it flows up and down puking out smaller volumes.
Drifting
Joined: Apr 2007
Posts: 1,970
Likes: 45
From: Cameron Park CA
There should be a FULL mark on the side tank of the radiator. From the video it looks like you might have it filled above the mark. Just a thought.
Another think, Harbor Freight sells infared heat guns pretty cheaply. It never hurts to have one so you know exactly what temps your engine is running at. You might be chasing a problem that doesn't exist.
All comments you are receiving about blocking off the air flow around the radiator, and the air dam are right on the mark. When everthing is right, Corvettes don't overheat.
and good luck with this,
Pete
Another think, Harbor Freight sells infared heat guns pretty cheaply. It never hurts to have one so you know exactly what temps your engine is running at. You might be chasing a problem that doesn't exist.
All comments you are receiving about blocking off the air flow around the radiator, and the air dam are right on the mark. When everthing is right, Corvettes don't overheat.
and good luck with this,Pete
Thread Starter
Drifting
Joined: Aug 2012
Posts: 1,650
Likes: 2
From: Tulsa Oklahoma
There should be a FULL mark on the side tank of the radiator. From the video it looks like you might have it filled above the mark. Just a thought.
Another think, Harbor Freight sells infared heat guns pretty cheaply. It never hurts to have one so you know exactly what temps your engine is running at. You might be chasing a problem that doesn't exist.
All comments you are receiving about blocking off the air flow around the radiator, and the air dam are right on the mark. When everthing is right, Corvettes don't overheat.
and good luck with this,
Pete
Another think, Harbor Freight sells infared heat guns pretty cheaply. It never hurts to have one so you know exactly what temps your engine is running at. You might be chasing a problem that doesn't exist.
All comments you are receiving about blocking off the air flow around the radiator, and the air dam are right on the mark. When everthing is right, Corvettes don't overheat.
and good luck with this,Pete
Thanks!
Drifting
Joined: Apr 2007
Posts: 1,970
Likes: 45
From: Cameron Park CA
FULL is usually embossed on the side tank a couple of inches below the filler neck. I can't tell you on mine because I have an aluminum radiator with no side tank. Every genuine copperbrass Corvette I have looked at has the FULL mark. In strong sunlight or with a good flashlight, you should have no trouble seeing it if it there. If no FULL mark, I think you want the coolant about 2" below the filler neck when cold. Othere will chime in to verify or say I'm wrong.
Pete
Melting Slicks
Joined: Feb 2006
Posts: 3,428
Likes: 5
From: Japan
Normally, when you hit the throttle and the thermostat is open you'll be able to look down into the radiator and see water flowing 'across' the radiator...I can't help but think there's a head gasket issue that may have occurred when it was initially running so hot. It would be a good idea to do a pressure check on the cooling system...can you get hold of a pressure tester? That would be the thing to do before pulling the heads back off...
Thread Starter
Drifting
Joined: Aug 2012
Posts: 1,650
Likes: 2
From: Tulsa Oklahoma
Normally, when you hit the throttle and the thermostat is open you'll be able to look down into the radiator and see water flowing 'across' the radiator...I can't help but think there's a head gasket issue that may have occurred when it was initially running so hot. It would be a good idea to do a pressure check on the cooling system...can you get hold of a pressure tester? That would be the thing to do before pulling the heads back off...
Last edited by FatCat; Feb 8, 2013 at 11:42 PM.
Melting Slicks
Joined: Feb 2006
Posts: 3,428
Likes: 5
From: Japan
With the cap on and the engine hot it should be pretty firm when running with the thermostat open. You did have the block magged when it was apart, right? I can't help but think that sudden jump in coolant flow is because combustion pressure is getting into the cooling system either past a leaking/blown head gasket or through a cracked cylinder wall. The only way to ruke that out is to do a pressure check on the cooling system. Is is pushing coolant out when the system is capped?
Last edited by birdsmith; Feb 9, 2013 at 10:43 AM.
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Thread Starter
Drifting
Joined: Aug 2012
Posts: 1,650
Likes: 2
From: Tulsa Oklahoma
With the cap on and the engine hot it should be pretty firm when running with the thermostat open. You did gave the block magged when it was apart, right? I can't help but think that sudden jump in coolant flow is because combustion pressure is getting into the cooling system either past a leaking/blown head gasket or through a cracked cylinder wall. The only way to ruke that out is to do a pressure check on the cooling system. Is is pushing coolant out when the system is capped?
Melting Slicks
Joined: Aug 2012
Posts: 2,548
Likes: 379
From: Woodinville WA
Le Mans Master
Joined: Dec 2007
Posts: 6,422
Likes: 591
From: McHenry Illinois
You've still got air trapped in the cooling system, the big question is whether the engine is putting compression gasses into the coolant or if it's just trapped air from the original fill. The liquid isn't compressable, when you rev it the air is compressing, evidenced by the coolant level going down. The water pump is pumping more water and squeezing the air bubbles. When you let off, the air bubbles are expanding again and pushing coolant out. If you have small holes drilled in the thermostat, the air will eventually work itself out if it's trapped from the initial fill. If the air is from compression gasses, it will keep acting like this or get worse. You can get a cooling system tester and check to see if it makes pressure after it's warmed up, indicating a compression leak. You can also get a test kit to determine if it's compression gasses in the cooling system.
Melting Slicks
Joined: Feb 2006
Posts: 3,428
Likes: 5
From: Japan
You've still got air trapped in the cooling system, the big question is whether the engine is putting compression gasses into the coolant or if it's just trapped air from the original fill. The liquid isn't compressable, when you rev it the air is compressing, evidenced by the coolant level going down. The water pump is pumping more water and squeezing the air bubbles. When you let off, the air bubbles are expanding again and pushing coolant out. If you have small holes drilled in the thermostat, the air will eventually work itself out if it's trapped from the initial fill. If the air is from compression gasses, it will keep acting like this or get worse. You can get a cooling system tester and check to see if it makes pressure after it's warmed up, indicating a compression leak. You can also get a test kit to determine if it's compression gasses in the cooling system.
Melting Slicks
Joined: Feb 2006
Posts: 3,428
Likes: 5
From: Japan
My own experience with blown head gaskets is that if combustion gases are escaping into the cooling system it will easily push right past whatever cap you've got on the radiator, I had a 22 lb. cap on a motor with a blown head gasket and it was blowing coolant out of the radiator...that's a good sign. Get this thing tested just to be sure.
Melting Slicks
Joined: Aug 2012
Posts: 2,548
Likes: 379
From: Woodinville WA
why are you folks scaring him? while it's possible (as it's possible there are unicorns), that the surging could be a leaking/blown head gasket - in all likelihood it's not
blown head gaskets bubble - little bubbles, and lots of them. If you take the cap off when there's a blown head gasket - there's a geyser. Surging, is not a head gasket.... it's a restriction in the system, most times, 99.99999999% of the time, it's a normal issue.
I agree with the air diagnosis, but I'm also concerned that he radiator is partially plugged.
blown head gaskets bubble - little bubbles, and lots of them. If you take the cap off when there's a blown head gasket - there's a geyser. Surging, is not a head gasket.... it's a restriction in the system, most times, 99.99999999% of the time, it's a normal issue.
I agree with the air diagnosis, but I'm also concerned that he radiator is partially plugged.
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
You have a heat gun. Check each exhaust tube near the head when warmed up after a short drive. All 8 should be close, not exactly the same but in the ballpark.
Thread Starter
Drifting
Joined: Aug 2012
Posts: 1,650
Likes: 2
From: Tulsa Oklahoma
I was going to get a tool yesterday but they wanted $170 deposit. Hahaha after all the crap I buy from them you would think they would trust me for an hour. Oh well I will borrow them from my buddy this week. Sooooo waiting! Hahaha
Safety Car
Joined: Sep 2012
Posts: 4,688
Likes: 41
From: Palm Harbor, Florida
what's the tool? use your wife's credit card and they refund when you bring it back...