Exhaust manifold gaskets, Which sealant is best.

[gas mart 1]

Can anyone advise me on which exhaust manifold gasket sealant is best. The one I have goes off like concrete very quickly , not giving enough time to get things in place and tightened up,
cheers
martin

[Number 7]

Assuming that you mean for the joint between the manifolds and the centre box branches where the olives are, I used to use exhaust assembly paste, but for the past couple of years have used Granville High Temperature red instant gasket, which works very well and stays flexible.

[gas mart 1]

Thanks for replying, I was reading in the bible that its advisable to use sealant on the Manifold to head gaskets, or is this not really needed. I have some assembley paste for the other joints.

[adam quantrill]

I use a bit of white flue/exhaust paste but if it starts going off quick just wet the surfaces you apply it to, and/or add a little water.

[Number 7]

gas mart 1 said:

Thanks for replying, I was reading in the bible that its advisable to use sealant on the Manifold to head gaskets, or is this not really needed. I have some assembley paste for the other joints.

I've never used anything on these gaskets - apart from anything else, its difficult to get everything aligned and bolted up quickly enough. Just make sure you get good quality composite gaskets.

[Hamish400]

I had trouble with failing exhaust manifold gaskets many years ago. Sorted by building up some spots on manifold flange where there was a very narrow area of gasket contact width with the face of the manifold flange, plus using wire reinforced gaskets (from RT Racing).
Hamish

[TVRleigh_BBWR]

I think the advice is given due to most of them not being very flat, but if you have manifolds off, make sur they are flat and have no pits or missing edges, you may need to flatten them all off and level with a file, or build with weld and then file / grind.
If this is done you won't need sealant just gaskets.

I had a history of my car having gasket sealing problems, but once I took them off and looked it was obvious why. 20% was missing on about 3 of 8, so bad I had to build up with weld and re-grind. but since then they have been perfect. I welded up some of the holes also

[adam quantrill]

I am going over to copper gaskets of my own manufacture.... they will last forever.

[TVRleigh_BBWR]

I can mill some up for you if you want to share.