Where is this coolant coming from?
Thread Starter
Instructor
Joined: Jun 2008
Posts: 233
Likes: 9
From: Marietta Ga
Where is this coolant coming from?
I have been dealing with a coolant "weep" for a couple years that is so small it dries up when I drive but it bugs the daylights out of me and I can't pinpoint it to fix it.
Location is drivers side head, just below the valve cover and above exhaust manifold connection. No.7 plug location and just below the valve cover bolt. Green spot right on the casting ridge. It never seems to turn into anything but always comes back after the car sits.
My intake seems dry up above at the joint. Anybody see or hear of this before? (73 L82)
Location is drivers side head, just below the valve cover and above exhaust manifold connection. No.7 plug location and just below the valve cover bolt. Green spot right on the casting ridge. It never seems to turn into anything but always comes back after the car sits.
My intake seems dry up above at the joint. Anybody see or hear of this before? (73 L82)
Team Owner
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
I have been dealing with a coolant "weep" for a couple years that is so small it dries up when I drive but it bugs the daylights out of me and I can't pinpoint it to fix it.
Location is drivers side head, just below the valve cover and above exhaust manifold connection. No.7 plug location and just below the valve cover bolt. Green spot right on the casting ridge. It never seems to turn into anything but always comes back after the car sits.
My intake seems dry up above at the joint. Anybody see or hear of this before? (73 L82)
Location is drivers side head, just below the valve cover and above exhaust manifold connection. No.7 plug location and just below the valve cover bolt. Green spot right on the casting ridge. It never seems to turn into anything but always comes back after the car sits.
My intake seems dry up above at the joint. Anybody see or hear of this before? (73 L82)
where the coolant crossover is?
most mani bolts need sealant for oil weep, I can't remember if the one over 7 goes into coolant?
Burning Brakes
Joined: Oct 2001
Posts: 1,241
Likes: 4
From: Okinawa Okinawa
May have to pull the manifold and reseat it. I think 7 goes into oil but it is worth a try to take it out, put sealant on it and retorque the bolts down. That would be easier than taking the entire thing off.
Any issues with a vacuum leak?
Any issues with a vacuum leak?
Thread Starter
Instructor
Joined: Jun 2008
Posts: 233
Likes: 9
From: Marietta Ga
I do only have 15" at idle with all intake manifold connections isolated....which has always seemed low. The weep seems to be above the exhaust manifold but below the valve cover. ...under the back valve cover bolt hole location.
Team Owner
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
is your coolant temp sensor on that side?
head bolts also need sealer
one thing about coolant, it can be blown back and collect a long way from the leak.
lets see, freeze plug?
Racer
Joined: Nov 2004
Posts: 485
Likes: 1
From: Oakville ON
different opinion
I think you have 2 unrelated issues.
The small coolant leak: add some sealant pellets (GM sells them, as do Prestone and Barr's). I have read that GM added it at the factory for some cars. It will not plug your heater core or rad. I have used it on several cars in the past and never had a problem (I prefer to grind them up in coolant and add to the rad as a slurry, then drive the car right away.
The manifold vacuum does seem low, but that is probably just a leak in one of the vac hoses or attachments. Best to find and fix that. I have an L-82 clone and get 17" - 18" at idle. My old DD with an LG4 had 20" at idle because of the mild factory cam.
The small coolant leak: add some sealant pellets (GM sells them, as do Prestone and Barr's). I have read that GM added it at the factory for some cars. It will not plug your heater core or rad. I have used it on several cars in the past and never had a problem (I prefer to grind them up in coolant and add to the rad as a slurry, then drive the car right away.
The manifold vacuum does seem low, but that is probably just a leak in one of the vac hoses or attachments. Best to find and fix that. I have an L-82 clone and get 17" - 18" at idle. My old DD with an LG4 had 20" at idle because of the mild factory cam.
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 99
From: Ontario
I think you have 2 unrelated issues.
The small coolant leak: add some sealant pellets (GM sells them, as do Prestone and Barr's). I have read that GM added it at the factory for some cars. It will not plug your heater core or rad. I have used it on several cars in the past and never had a problem (I prefer to grind them up in coolant and add to the rad as a slurry, then drive the car right away.
The manifold vacuum does seem low, but that is probably just a leak in one of the vac hoses or attachments. Best to find and fix that. I have an L-82 clone and get 17" - 18" at idle. My old DD with an LG4 had 20" at idle because of the mild factory cam.
The small coolant leak: add some sealant pellets (GM sells them, as do Prestone and Barr's). I have read that GM added it at the factory for some cars. It will not plug your heater core or rad. I have used it on several cars in the past and never had a problem (I prefer to grind them up in coolant and add to the rad as a slurry, then drive the car right away.
The manifold vacuum does seem low, but that is probably just a leak in one of the vac hoses or attachments. Best to find and fix that. I have an L-82 clone and get 17" - 18" at idle. My old DD with an LG4 had 20" at idle because of the mild factory cam.
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Racer
Joined: Dec 2009
Posts: 415
Likes: 10
From: Richmond Va
Head bolts go through to coolant valleys. Make sure they have sealant on them. I had the same problem once and one of my bolts had sealant, but just not enough. One tube of RTV and she was fixed.
I was thinking freeze plug too, but if it is that high, I would count that out. Good luck.
I was thinking freeze plug too, but if it is that high, I would count that out. Good luck.
Racer
Joined: Dec 2009
Posts: 415
Likes: 10
From: Richmond Va
