Antifreeze leak......how?
Thread Starter
Melting Slicks
Joined: Jan 2003
Posts: 2,713
Likes: 31
From: Shreveport LA
LA Events Coordinator
Antifreeze leak......how? UPDATE UPDATE UPDATE!!!!
I have noticed lately that on my intake manifold, in the front, (driver's side) there's a very, very small puddle in the area where one of the bolts that hold down the intake (SEE PICTURE)....no where else, just in the area pointed to in the picture. When I say small, I mean small...but none the less, a leak. I've tighten the bolt to the manifold, tightened the upper radiator hose and the thermostat housing unit. I don't want to tighten anything too much and strip bolt, screw or anything. Any suggestions? Am I overlooking something...like I should tighten the left rear wheel lug nuts because they're connected..
Last edited by vetteguy75; Jan 29, 2012 at 09:09 PM.
Drifting
Joined: Jul 2002
Posts: 1,995
Likes: 110
From: Garland Texas
The oil is coming up thru the threads. Remove the bolt, clean the threads and put sealer on them. All the intake bolts are exposed to oil except the 4 corner bolts which are blind holes.
Mike
Mike
Le Mans Master
Joined: Mar 2008
Posts: 5,948
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From: Oxford MA-----You just lost the game!!!!
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
I can't see the picture, but the manifold coolant passages are at the front and rear of the heads. I expect you've got a leaking gasket right at that front cooling passage.
Time for a gasket change...and since you've got the intake off...cam upgrade?
Time for a gasket change...and since you've got the intake off...cam upgrade?
Burning Brakes
Joined: Jan 2012
Posts: 943
Likes: 73
If the water is actually pooling up on the intake manifold, sealant on the threads should stop the leak. If the water is leaking from the edge of the manifold and pooling on the cylinder head/edge of manifold, then I would replace the intake manifold gaskets. I can't tell from the photo if the water was sitting around where the head of the bolt is. Usually, if antifreeze has been sitting on an aluminum manifold for awhile, there is some dis-colorization.
Safety Car
Joined: Jun 2004
Posts: 4,372
Likes: 223
From: Beecher Illinois
I agree with the intake manifold water passages leaking....new gaskets.
I had one Vette with the rear passage/blockoff leaking, another with the front passage leaking, both got new gaskets.
Another I was tearing down things under the hood to do some detailing. As soon as I removed the front intake bolt that also holds the AIR bracket, water dripped. New gaskets.
Just tightening seldom helps.
I did notice the one that was leaking at the front passage only leaked after running the engine and shutting it off. As it cooled down it would drip a little.
If you have an aluminum manifold be prepared for the bolt(s) at the water passage to be seized to the manifold. A reaction between the steel, aluminum, and water. If it won't break loose and the head breaks off not really a big deal. Just carefully work the manifold off the broken remaining stud.
Shouldn't take much effort to then remove the remaining bolt.
I had one Vette with the rear passage/blockoff leaking, another with the front passage leaking, both got new gaskets.
Another I was tearing down things under the hood to do some detailing. As soon as I removed the front intake bolt that also holds the AIR bracket, water dripped. New gaskets.
Just tightening seldom helps.
I did notice the one that was leaking at the front passage only leaked after running the engine and shutting it off. As it cooled down it would drip a little.
If you have an aluminum manifold be prepared for the bolt(s) at the water passage to be seized to the manifold. A reaction between the steel, aluminum, and water. If it won't break loose and the head breaks off not really a big deal. Just carefully work the manifold off the broken remaining stud.
Shouldn't take much effort to then remove the remaining bolt.
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Verdad Gallardo
Team Owner
Joined: Jan 2006
Posts: 37,637
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From: Crossville TN
Well, the bolt shouldn't be exposed to coolant. But, casting porosity, little tear on the inside portion of a gasket next to the bolt...lots of 'funny' things can cause it to leak--oil or coolant.
Remove the bolt, clean it and put some #2 Permatex or black RTV on it (don't use general purpose silicone
), blow out the threads well and put it back together. Torque to about 22-24 ft-lbs [normally 30 ft-lbs 'dry'...but you have sealant on the threads which acts as a lubricant]. Let it set overnight (at least) to cure; if in cold environment, maybe longer. It needs to be fully cured before you throw pressure/heat/water/oil at it.
If that doesn't dry it up, then you can consider new gaskets.
Remove the bolt, clean it and put some #2 Permatex or black RTV on it (don't use general purpose silicone
), blow out the threads well and put it back together. Torque to about 22-24 ft-lbs [normally 30 ft-lbs 'dry'...but you have sealant on the threads which acts as a lubricant]. Let it set overnight (at least) to cure; if in cold environment, maybe longer. It needs to be fully cured before you throw pressure/heat/water/oil at it.If that doesn't dry it up, then you can consider new gaskets.
Intermediate
Joined: Jul 2010
Posts: 37
Likes: 0
From: Fowlerville Mi.
Is that a plug on the intake right below the letter "P" in your picture, if so my Edelbrock intake used to leak a little coolant right where yours does, only after the motor was hot, it was leaking from the plug.
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
I can't view the photo either, but I'll just say that water finds it's own level, and if you don't actually see the fluid leaking out, it could be leaking from any number of places.
Scott
Scott
Burning Brakes
Joined: Nov 2006
Posts: 893
Likes: 7
From: Orange Park Florida
Looks like the plug you are referring to is for a coolant temp sending unit. The leak is probably there. Drain a little antifreeze, remove the plug, add some sealant then reinstall.
Good luck
Good luck
Thread Starter
Melting Slicks
Joined: Jan 2003
Posts: 2,713
Likes: 31
From: Shreveport LA
LA Events Coordinator
Update*update*update!
Hey Guys,
I removed the intake manifold bolt where the leak was evident, cleaned the threads to the bolt with a wire brush (it was quite dirty & oily) and cleaned the intake manifold threads, put teflon (high temp) sealant on the bolt, reinstalled it and torqued it to 30ft/lbs. Went on a 45 mile cruise on the interstate (avg speed 78 mph/3500 rpms). Checked the intake and its DRY!!!It's fixed.... No coolant
Thanks for the info!!!!
I removed the intake manifold bolt where the leak was evident, cleaned the threads to the bolt with a wire brush (it was quite dirty & oily) and cleaned the intake manifold threads, put teflon (high temp) sealant on the bolt, reinstalled it and torqued it to 30ft/lbs. Went on a 45 mile cruise on the interstate (avg speed 78 mph/3500 rpms). Checked the intake and its DRY!!!It's fixed.... No coolant
Thanks for the info!!!!
