Intake Manifold Coolant Leak
Thread Starter
Instructor
Joined: Sep 2017
Posts: 134
Likes: 6
From: Noblesville Indiana
Intake Manifold Coolant Leak
When I built my engine I put the intake manifold gaskets in without the use of RTV. The coolant leaked from cylinders 7 and 8. I removed the carb, distributor, intake, etc and put new gaskets on using both RTV black and water pump gasket maker around the coolant passages to seal it better. I am still getting (albeit minor and far better than before) a coolant leak over cylinder 8. I am at a loss at this point and don't know how to seal it any better. Any suggestions would be greatly appreciated.
Thread Starter
Instructor
Joined: Sep 2017
Posts: 134
Likes: 6
From: Noblesville Indiana
Sorry about that Gold, I should've included those details in my post. It's a small block. The heads are new Edelbrock aluminum heads and the intake is an aluminum one off an 80 L-82.
Burning Brakes
Joined: Jan 2017
Posts: 1,096
Likes: 213
From: The Buckle of the Bible Belt. Joplin Mo
The Intake manifold sounds cool. I love retro parts, but that could be part of the issue. Its probably seen plenty of miles. Maybe some RTV is in order in this case. Doesn't sound like its off by much. FWIW. When I was looking into aluminum heads, my machinist advised me to bring the new heads in when they arrived so they could be checked. I asked why
Apparently they are far from perfect right out of the box.
Apparently they are far from perfect right out of the box.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
Start over ... again .
Maybe you're not getting bolts tightened equally; they can be hard to get to.
Try these ... small 12-point heads
https://www.summitracing.com/parts/a...7010/overview/
OR
https://www.summitracing.com/parts/sum-g1491
Maybe you're not getting bolts tightened equally; they can be hard to get to.
Try these ... small 12-point heads
https://www.summitracing.com/parts/a...7010/overview/
OR
https://www.summitracing.com/parts/sum-g1491
Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
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If you're married to that intake, I would check the heads and intake with a machinist flat edge or square. If you cant see the problem that way, then unbolt the heads and take it all to a machinist
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
A wise, old house painter once told me that the prep work was 90% of a successful paint job. You are not painting but the prep work for laying an intake is about the same.
Never use metal to remove old gasket material. Use a plastic scraper.
Always wipe down BOTH mating surfaces with Acetone. Or the best sealant in the world will never adhere.
Torque the bolts in the proper sequence. Skip trying to use universals and sockets in some places.
Use Edelbrocks Gastinich (sp?) on the bottom of the gasket, let it set-up-tacky. Then apply to the top side of gasket.
The Right Stuff on the china walls.
Should be good to go.
Never use metal to remove old gasket material. Use a plastic scraper.
Always wipe down BOTH mating surfaces with Acetone. Or the best sealant in the world will never adhere.
Torque the bolts in the proper sequence. Skip trying to use universals and sockets in some places.
Use Edelbrocks Gastinich (sp?) on the bottom of the gasket, let it set-up-tacky. Then apply to the top side of gasket.
The Right Stuff on the china walls.
Should be good to go.
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,209
Likes: 9,347
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
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Thread Starter
Instructor
Joined: Sep 2017
Posts: 134
Likes: 6
From: Noblesville Indiana
Hey guys, thank you all for your words. I pulled the intake this weekend and sent it to the guy who machined my block. I should have it back for when I get back home this weekend.
I have used RTV and water pump gasket maker in the past and did this time but it still leaked, which led me to the conclusion that the intake was warped. I removed the gasket and RTV with a plastic scraper and wiped it clean with Brake Clean and isopropyl alcohol so it'll be nice and clean for when the intake goes back in.
I'll keep you all posted!
I have used RTV and water pump gasket maker in the past and did this time but it still leaked, which led me to the conclusion that the intake was warped. I removed the gasket and RTV with a plastic scraper and wiped it clean with Brake Clean and isopropyl alcohol so it'll be nice and clean for when the intake goes back in.
I'll keep you all posted!
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Depending on what the machine shop does and how much milling, this may be a scenario where the thicker gasket is used. FelPro has both the 0.060 thick and the 0.120 thick which is # 1255. Ask your machinist which gasket they recommend regarding the milling / metal removal and alignment of not only the ports but the bolt holes too.
You will have to port match the gasket after obtaining measurements of the port on the cyl head. Then look at Summit for the correct size and thickness you need.
You will have to port match the gasket after obtaining measurements of the port on the cyl head. Then look at Summit for the correct size and thickness you need.