Intake manifold leaks oil at china wall seals

[ezcruisn71]

Well I have an oil leak at my front and back "china wall" area on the block between the intake and the engine block.
I have been working on these engines for a while now and there seems to be a lot of discrepancy on whether to use the rubber seals on this area or to use RTV this area.
Last time I installed this intake I used RTV and now it leaks in the front and back?
This time I am going to try the rubber seals and RTV.
Anybody have anything that has worked good for them?
I am tired of dealing with this.

[1BADAIR]

breathers on both valve covers? or pcv?
most people wont use the gaskets. only rtv

[ezcruisn71]

I run a PCV on the Right side and I breather in the Left side.
The wife complained to much about the oily smell inside the car when I ran the 2 breathers,
so I installed the PCV valve.

[Kwazrollinz28]

I was blowing the rear intake seal out all the time, pissed me off, i was tired of burning oil on my Long tubes, so i installed 2 breathers one on each side and then re-did the intake silicon and now it doesnt leak at all, and i made damn sure to use the whole tube hahahah. i am sick of removing the LT1 intake manifold pain in the ass

And on a side note this time i went to lowes and bought brand new bolts and Lock nut washers and followed the bolt down sequence. Also i never smell any oil smells...

[ezcruisn71]

Are you using the Black RTV from GE?

[Kwazrollinz28]

Im using the ULTRA black silicon. what i do is make 1 big bead across, then put another big bead on top of that bead and smother it together. so its gauranteed no leaks, just let the car sit for 40hours unless you want silicon in your oil pickup lol

[JoeliusZ28]

I used Permatex "Right Stuff" instant gasket as recommended by people on cz28.com and it held up perfectly for 2 years. But recently it has started leaking like a siv

[WMCCjames]

Those are the number 1 leak spots for all SBC's. No matter what you do, it will develope a leak over time. I've done every combination possible and no matter what, they always develope a leak. The best method I have had to date was to clean both surfaces with lacquer thinner and prick punch little dimples in the sealing surfaces. Then apply RTV of choice. Let that sit for about 15 minutes then install and torque down properly. Let the car sit for a couple days before firing.

[ezcruisn71]

Sounds like someone needs to come up with a good way of sealing these intakes? Someone could make some good money on this fix.

[white97z28]

Those are the number 1 leak spots for all SBC's. No matter what you do, it will develope a leak over time. I've done every combination possible and no matter what, they always develope a leak. The best method I have had to date was to clean both surfaces with lacquer thinner and prick punch little dimples in the sealing surfaces. Then apply RTV of choice. Let that sit for about 15 minutes then install and torque down properly. Let the car sit for a couple days before firing.

I wondered what the dimples on my block where my intake bolts down were for haha

[Fbomb]

Gotta let the rtv cure a bit before you bolt it on so that you'll have a tight seal vs. the rtv squishing out of the groove.

[white97z28]

I also only use Ultra Black not rtv because ultra black is made for use with places where oil is present

[WMCCjames]

I also only use Ultra Black not rtv because ultra black is made for use with places where oil is present

Ultra Black is RTV...RTV stands for Room Temperature Vulcanization....that's how it cures.

[ezcruisn71]

Well, I let the intake manifold set over night and I leak checked it yesterday and so far I don't have any leaks!
Now let's just hope it stays that way!

[ThreeHonks]

I always use "The Right Stuff" and I dimple only the intake manifold with a punch. I spend a lot of time putting dimples on it, im not talking 1 or 2... like 80