Hi guys,

I finally got finished putting new intake gaskets on my 94 460. Unfortunately the China wall seals leaked once I started it up.

I am prepared to do this again, but I wanted to get all my facts straight so I don’t have to do it a third time.

1. I’ve ruled out using the provided fel-pro rubber seals, and instead opted to use silicone. Is this the right thing to do?

2. How thick of a bead should I be using? And does it have to be a consistent bead?

3. I previously had put just a thick beat of RTV on the block side. But I heard it suggested to put a bead on both the intake and the block is correct or will one bead on the block suffice?

4. Should I use the right stuff, ultra black or something else?

5. I really don’t want to have to do this again so any tips or pointers would be great

Thanks!!

 

When you use the rubber seals, did you put RTV on them? You should only use RTV on the 4 corners to seal them to the gasket. If you put it on the sealing surface, it makes them slippery and then they push out when you torque the intake down. Is this perhaps what happened?

 

When I did my intake I researched and everyone said to just RTV the corners. I used the rubber Fel-Pro gaskets Right Stuff in the corners only and the proper torque sequence/procedure and that was 50k miles ago and I havent had a leak.

 

I seldom use the factory rubber seals included in a gasket set
I use clear silicone and have for years and years
No need to glom it all over, just a 1/4 inch bead on both is sufficient
A good visual inspection as you torque it down is key
You want to see that silicone get mashed out, all the way along the sealing surfaces, and out both corners
Let dry for 24 hours before returning to service
If the PCV system has an issue or is plugged up, the crankcase pressure can blow the end seals out
Verify the PCV valve and system operation with a piece of paper held over the vent
If you need to know how to do that, I can explain

 

I ditch the end seals and just use silicone.

First I cut some threaded rod and screwed them into the 4 corner bolt that are straight up and down. This allows you to install the side gaskets without them sliding around and it guides the intake down more evenly onto the silicone.

Next, clean the block, intake, bolt holes and bolts with Brakeclean or something similar to remove all oil residue.

Install your 4 temporary corner studs. Test fit the intake on so you can see the gap on the ends so you can get an idea on how much of a bead of silicone that you need. Make sure your side gaskets are in place as it will raise the height of the intake.


Lift the intake back off and remove the side gaskets. Lay down your bead of silicone. I use the Ultra Black but the Right Stuff works too. When laying down the silicone, also go up the head surface about a 1/4” so it will be under the corner of the gaskets. Install the side gaskets. Add a little silicon on the gasket corner again.

Install the intake, lightly and evenly tighten the four corners with your temporary studs. Wait 45-60 minutes. Your letting the silicone set a little bit.

Coat all your bolts with your favorite thread sealer. I like the Loctite 567 anaerobic Teflon paste. Install all your bolts and lightly tighten. Remove your temporary studs and install those bolts.

Torque your bolts down in the proper sequence in 2-3 stages until you get to your final torque.

Let it sit for 24 hours before adding coolant, you want your bolt sealant to set up.

 

i use black rtv only,build up a good bead on the rails drop the intake down

 

Black is unsightly
I use clear
I do use ultra grey on rear end cover plates
That ultra black is about the best there is, but is so messy, I leave it at the parts store
Same with the ultra grey, good stuff but messy as hell
You can use just about anything but plumbers white

 

Lately I use the Ultra Black in the cheese whizz cans. It’s like a Cutis-Mathis TV, expensive but darn well worth it.

 

i tried the clear a few times, not very oil and gas resistant, caused leaks, last engine i built was a 406 nail head where i used the right stuff gasket maker , amazing product .