Valley Gasket, Tin or Composite?

[AM400]

Need to change the valley gasket, the original is tin and rusting! any benefits in using the composite one other than no rust!
Also any pitfalls to look out for when removing the inlet? I take it it can be removed as a unit with injectors etc still in place once the plenum top has been removed.
Cheers

[pwd95]

The composite gasket I fitted to my wedge looked & felt very good quality. Stripping the top end is pretty straight forward as you say. A good opportunity to clean everything up & replace any worn pipes & dodgy jubilee clips.

[AM400]

Wyn,

Did you use any sealer with the composite gasket? or is it a good enough seal to start with.

[pwd95]

I used a little Blue Hylomar around the outer edges and under the valley gasket clamp rubbers. Just need to make sure no outside air gets in there. Be relatively generous with it under the trumpet base and the plenum. I didn't use enough 1st time & it was all over the shop when I started it. Had to re-seal it. Good luck.

[TVRleigh_BBWR]

I think composite is the way to go now.
The very early composite / rubber ones did have problems but that has now been sorted.

[Hormone]

AM400 said:

Need to change the valley gasket, the original is tin and rusting! any benefits in using the composite one other than no rust!
Also any pitfalls to look out for when removing the inlet? I take it it can be removed as a unit with injectors etc still in place once the plenum top has been removed.
Cheers

I have just done this on the 400Se. The head had to be skimmed and the manifold holes altered due to the increased thickness of the gasket so not as straight forward as first thought.

[djc1001]

Hormone said:

AM400 said:

Need to change the valley gasket, the original is tin and rusting! any benefits in using the composite one other than no rust!
Also any pitfalls to look out for when removing the inlet? I take it it can be removed as a unit with injectors etc still in place once the plenum top has been removed.
Cheers

I have just done this on the 400Se. The head had to be skimmed and the manifold holes altered due to the increased thickness of the gasket so not as straight forward as first thought.

Don't understand this ?
Took tin on off put composite on - no mods - I used a little grease on the faces to help it pull down into the V and goo around the clamps as previous post

david

Edited by djc1001 on Monday 26th May 12:17

[Boosted LS1]

^ Because the heads were skimmed they are nearer to eachother ie the 'V' has narrowed. Also, the bolt holes are now lower down, nearer the crank centreline due to the head having less height.

[stainless_steve]

djc1001 said:

Hormone said:

AM400 said:

Need to change the valley gasket, the original is tin and rusting! any benefits in using the composite one other than no rust!
Also any pitfalls to look out for when removing the inlet? I take it it can be removed as a unit with injectors etc still in place once the plenum top has been removed.
Cheers

I have just done this on the 400Se. The head had to be skimmed and the manifold holes altered due to the increased thickness of the gasket so not as straight forward as first thought.

Don't understand this ?
Took tin on off put composite on - no mods - I used a little grease on the faces to help it pull down into the V and goo around the clamps as previous post

david

Edited by djc1001 on Monday 26th May 12:17

Maybe mixed up with head gasket

[stainless_steve]

AM400 said:

Need to change the valley gasket, the original is tin and rusting! any benefits in using the composite one other than no rust!
Also any pitfalls to look out for when removing the inlet? I take it it can be removed as a unit with injectors etc still in place once the plenum top has been removed.
Cheers

How will you polish a composite gasket Andy

[GreenV8S]

AM400 said:

I take it it can be removed as a unit with injectors etc still in place once the plenum top has been removed.

You'll need to work down removing each layer in turn. Don't be put off, it's a relatively quick and easy job. For example you'll need to take the fuel rail off, but if you keep the injectors in the rail you can just move the whole thing out of the way and won't need to depressurize it. Just make sure you're absolutely paranoid about keeping tools and parts away from the intake system because if you drop anything in and notice it, it'll be a right pig to get out. And if you don't notice it, there is a real danger of lunching the engine when you come to start it up. I suggest you mask off the openings as you go to minimise the risk but still be on the lookout for anything that could potentially fall anywhere near the intake.

[AM400]

Thanks for the comments and tips, will be ordering composite gasket soon and hoping for the best when fitted!
And Steve, that had actually crossed my mind

Cheers

[stainless_steve]

I can believe it Andy