Leaking Head Gasket?
Thread Starter
Burning Brakes
Joined: Mar 2006
Posts: 793
Likes: 1
From: Houston Texas
Leaking Head Gasket?
What would be the best, easiest, simplest method of determining if a head gasket were bleeding compression into the coolant/waterjacket? Maybe a compression check? Or pressurize the coolant system for a leak check?
Some other way I haven't thought of?
Thanks!
Some other way I haven't thought of?
Thanks!
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Pull the radiator cap and start the engine- if compression is getting into the cooling system, it'll blow bubbles in the fill neck.
Are you losing coolant? Water in the oil? Oil in the water? Sweet smelling white smoke out the exhaust?
Coolant loss can be a crack in a head, bad intake gasket, bad head gasket. Even a loose or seeping head bolt.
Are you losing coolant? Water in the oil? Oil in the water? Sweet smelling white smoke out the exhaust?
Coolant loss can be a crack in a head, bad intake gasket, bad head gasket. Even a loose or seeping head bolt.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
If you have a leaky head gasket, the compression stroke might put some bubbles in the coolant, but the intake stroke should suck some coolant into the fuel charge and produce white smoke [steam] in your exhaust...only on one side (unless you don't have separated dual exhaust tubes).
Racer
Joined: Apr 2006
Posts: 340
Likes: 0
From: Warrensburg MO
What is happening to make you ask this question?
Thread Starter
Burning Brakes
Joined: Mar 2006
Posts: 793
Likes: 1
From: Houston Texas
Had the car out yesterday and after 20 minutes or so it began to lose coolant through the over-flow off the surge tank. Probably lost a gallon of coolant. Has been running flawlessly since last July when I got it back on the road.
Surge tank is almost empty this morning. Pulled the plugs and all look similar, appear as they did last November when I had them out for an inspection. Nothing that looks like one plug may have been exposed to coolant. No smoke through the pipes. Thermostat, fan clutch, radiator are all recent, quality parts. Lower hose coil is intact. Nothing obvious, save for what might be more foaming in the tank than I have previously seen. Am trying to adhere to the KISS principal, and may replace the thermostat this morning.
Surge tank is almost empty this morning. Pulled the plugs and all look similar, appear as they did last November when I had them out for an inspection. Nothing that looks like one plug may have been exposed to coolant. No smoke through the pipes. Thermostat, fan clutch, radiator are all recent, quality parts. Lower hose coil is intact. Nothing obvious, save for what might be more foaming in the tank than I have previously seen. Am trying to adhere to the KISS principal, and may replace the thermostat this morning.
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
Frm your last post, it seems pretty clear that you have either a gasket or head problem.
Pretty common symptoms here in S Florida.
Have done 3 last year like this and have another one right now.
Sometimes it's hard to diagnose because you won't have consistant symptoms. The key is you are blowing over the pressure cap, losing coolant and no smoke or coolant in oil which means you are only pushing it.
Sometimes you can use an exhaust gas sniffer (simplest) in the rad cap neck, fluid tester or even test each cylinder with valves closed with high pressure air. Sometimes the leak will be when cold, other times hot and sometimes you will not be able to test for it conclusively.
With the corvette rad neck opening being below the uppermost tube, it's almost impossible to see bubbles.
So if your observations are correct, then simply thru elimination, you have found the problem. But first, try known good rad cap, since you didn't mention that.
Have the heads pressure checked and/or fluxed while they're off and use good gaskets, and I preferr ARP bolts.
Be happy this is all it is.
Forgot to mention that this assumes your cooling system is clean internally.
Pretty common symptoms here in S Florida.
Have done 3 last year like this and have another one right now.
Sometimes it's hard to diagnose because you won't have consistant symptoms. The key is you are blowing over the pressure cap, losing coolant and no smoke or coolant in oil which means you are only pushing it.
Sometimes you can use an exhaust gas sniffer (simplest) in the rad cap neck, fluid tester or even test each cylinder with valves closed with high pressure air. Sometimes the leak will be when cold, other times hot and sometimes you will not be able to test for it conclusively.
With the corvette rad neck opening being below the uppermost tube, it's almost impossible to see bubbles.
So if your observations are correct, then simply thru elimination, you have found the problem. But first, try known good rad cap, since you didn't mention that.
Have the heads pressure checked and/or fluxed while they're off and use good gaskets, and I preferr ARP bolts.
Be happy this is all it is.
Forgot to mention that this assumes your cooling system is clean internally.
Last edited by noonie; Mar 27, 2010 at 12:45 PM.
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Thread Starter
Burning Brakes
Joined: Mar 2006
Posts: 793
Likes: 1
From: Houston Texas
Well, first, thanks to all you guys for the replies. Helps to have the ideas thrown around to make you think. I picked up the sniffer kit to check the coolant for hydrocarbons. Tested negative, good news. So I had to stop and think again. Lo and behold, there's the answer staring me in the face.
OK, confession time. Few days ago I got some original clamps and other stuff for the car. Yesterday morning I went out to put a bunch of it on. Short version is, in swapping the radiator bypass hose clamps and putting on the overflow hose from Doc R., I put the bypass hose where the overflow goes and vice versa.
I'm not the most experienced mechanic on CF, but I do have a whole lot of experience. 35 years worth. I certainly should know better. The good news is I don't have to tear down that expensive motor.
So, I'm getting old and stupid. There you have it. Thank God for looking after me.
PS. Tonight I'm gonna take that dude out and let the world know once again the sound of the Generals triple deuces and factory side pipes.
Dan
OK, confession time. Few days ago I got some original clamps and other stuff for the car. Yesterday morning I went out to put a bunch of it on. Short version is, in swapping the radiator bypass hose clamps and putting on the overflow hose from Doc R., I put the bypass hose where the overflow goes and vice versa.
I'm not the most experienced mechanic on CF, but I do have a whole lot of experience. 35 years worth. I certainly should know better. The good news is I don't have to tear down that expensive motor.
So, I'm getting old and stupid. There you have it. Thank God for looking after me.
PS. Tonight I'm gonna take that dude out and let the world know once again the sound of the Generals triple deuces and factory side pipes.
Dan
Thread Starter
Burning Brakes
Joined: Mar 2006
Posts: 793
Likes: 1
From: Houston Texas