So I now have all the parts required to do this job except for the exhaust gaskets. Will I need to replace them after having dropped the exhaust to do the sway bar bushes etc or do they usually survive this process? Our very good friends at Italian Automotive Spares don't carry them in stock.
If the exhaust flange gasket or the manifold gasket is still in reasonable condition (not falling apart, no bits missing), I've had success painting the old gasket with a thickish layer of 'silver frost' paint (an oil based paint containing particles of aluminium). Obtain a tin of this paint, open it, pour off as much off the clear liquid laying on top of the thick 'sediment' as you can, then mix in the remaining fluid into the sediment with a stick (whatever) to make a uniform paste. The 'paint' basically consists of aluminium particles held together with a binding medium (ie. the liquid component of the paint, whatever that actually is). Now clean the old gasket and surfaces of the components being 'gasketed' as well as you can.
Paint the gasket with a brush and allow to dry (which should take half an hour or so). Repeat. You want a thickish layer of the 'silver frost' paint, but it doesn't have to be a completely even layer (but as even as reasonably possible). The thickish dried paint layer won't be completely hard, but somewhat 'malleable'. When the gasket is squeezed by the clamping pressure (of the flange or manifold fasteners) the paint gets squashed 'flat', and the thickness evens out. The aluminium particles move and fill any voids in the gasket itself and / or in the metal sufaces (some of the 'paint' will be squeezed out at the edges of the gasket). The paint cures / hardens / sets with engine and manifold heat in use. I've used the paint successfully even if it has become a bit lumpy over time (since the last time I opened the tin). It has never failed to work for me, and I have even used it on head gaskets both new and re-used.
This method of sealing suspect gaskets was told to me many years ago, by an old bloke who made custom gaskets for a living (gaskets for anything from racing car engines, vintage cars, to massive ship diesels etc. etc.). His business ('Universal Gaskets' from memory, but I could easily have that wrong) was a charming ancient establishment located in Balmain or pehaps Rozelle, in a rust coloured tin shed, time having stripped it of any remnant galvanising. No longer there, a lost gem...
Regards,
John.
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