coolant leak
Thread Starter
Burning Brakes
Joined: Nov 2004
Posts: 1,028
Likes: 0
From: San Antonio Texas
coolant leak
getting a slight "weeping" of coolant out of the front of the intake manifold gasket. doesn't run out. doesn't drip, doesn't do it all the time. occasionally shows enough to feel wet to the touch. i've drained coolant and engine oil and examined both. no evidence of coolant in oil or oil in coolant. engine runs fine. no smoke or unusual smell from exhaust. how concerned should i be about this? aluminum (GM) low profile manifold. i've been told these manifolds are know for doing this.
Le Mans Master
Joined: Jun 2003
Posts: 5,446
Likes: 2
From: Not Correctly Restored Stingray Fla.
Check around your thermostast housing. Or if you have a heater hose connected up front there, check that. Otherwise I can not think of anything else other than a cracked intake manifold.
Thread Starter
Burning Brakes
Joined: Nov 2004
Posts: 1,028
Likes: 0
From: San Antonio Texas
shouldn't i be able to see that? or at least see coolant seeping out of a crack? it shows on the "extruded" part of the RTV gasket. no where else. like it must be coming out between the manifold and the gasket. unless it is coming down from the thermostat or hose and not leaving any evidence up there???
Instructor
Joined: Nov 2001
Posts: 175
Likes: 0
From: St Louis MO
You could go to your local AutoZone and use their pressure tester and do a leak check on your cooling system. If you are not getting any anti-freeze in the oil, and you don't want to take out the intake manifold to reseal it, then I would use a couple of those sealing tabs that GM sells.
Instructor
Joined: Nov 2001
Posts: 175
Likes: 0
From: St Louis MO
They are pellets that they grind up and put in the radiator to eliminate any seepage that might occur from the cooling system. You can get them from GM, a couple of bucks for half a dozen. You should only need to put one in.
Melting Slicks
Joined: Jul 2004
Posts: 2,577
Likes: 2
From: Long Island New York
I would pull the intake and reseal it, I would not use the pellets that GM sells. My daughter had a small coolant leak in her '02 Grand Am, and the Dealer threw in these pellets to seal it. The leak did not stop and they had to pull the intake manifold and replace the intake gasket anyway. The pellets clogged up her cooling system and they had to power flush her car in order to get the circulation in the sytem back to normal. Lucky for her the job was under the manufactuers warranty. 
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Thread Starter
Burning Brakes
Joined: Nov 2004
Posts: 1,028
Likes: 0
From: San Antonio Texas
yeah, i thought about that. what's the proper sequence on a 350. i don't ever see a sequence for manifolds, only heads. how much torque? aluminum manifold and heads. thanks.
Le Mans Master
Joined: Jun 2003
Posts: 5,446
Likes: 2
From: Not Correctly Restored Stingray Fla.
Originally Posted by greyghost79
yeah, i thought about that. what's the proper sequence on a 350. i don't ever see a sequence for manifolds, only heads. how much torque? aluminum manifold and heads. thanks.
35lbs and start with the center bolts, criss-cross side to side and work your way to the end bolts.
I would do a pressure check. If you do not have the tool, rent one. Do not let those guys at any of those "auto parts" stores go near your car or even try to help. Do NOT use any sealant tabs!!! Find the leak first.
