RE: Cylinder Head Gasket Compounds.

[Mike Wattam <101714.1343@domain.elided>]

NEVER use sealing compounds on Stag cylinder head gaskets.  They are
located purely by the positioning of the inlet manifold and their
relationship to the head, so as you tighten down the heads and inlet
manifold the heads have to 'creep' on the block surface.  It is correct to
lightly grease the gaskets all over immediately before fitting to
facilitate the 'creep', and also allows the gasket to move to fill any
irrelguarities in the head surface. 

I have used this method on several Stag head gaskets over the years
including my own car and some other vehicles, and no failure yet.

If a cylinder head gasket fails, it will always be from the flame ring and
there just isn't a sealant which will stand those temperatures, not even
Loctite!

Note, Stag head gaskets can also fail from the waterways and up the head
studs (woe, woe, woe), so the integrity of the flame rings may still be
intact and the only visible symptom slight water loss.  This is most likely
to occur after using a gasket sealant as it is impossible to get it on flat
and even, so local high and low pressures exist.  It also reduces the
pressure load on the flame rings, so they are more prone to fail.

Oh, and just to finish off the head gasket sermon, if the head gaskets were
originally fitted greased, not only can the heads be removed easily, but if
there is a SLIGHT leak it is possible to wind off the nuts slightly and
re-torque them to make the head gaskets seal again.

Mike Wattam
Triumph Stag Register