Worth it? Used one years ago but seemed a bit messy and was feart it may contaminate the oil ways. This engine has good surfaces and no warpage.

good/bad idea?

Bad idea
Not needed
Some OEM gaskets have a small bead but if faces are flat and clean no need

I wouldn't use any sealant with a head gasket, unless it was part of the required process.

it's an old landy's petrol head, a normal fiber gasket rather than the copper one

Modern Fibre gaskets glue themselves to the head and block faces. You don't want to put anything on them which will stop that happening. You also want to clean the faces of the Head and Block with something like brake cleaner to de-grease the surfaces just before assembly.

[Edited on 25/2/14 by DW100]

that's good point, ok I'll not use any sealent then

Thanks

Rolls Royce use weld seal on all there head gaskets...

we use a very fine layer of weldseal on all of our head gaskets on all our race engines we build at work.

its a mattter of opinion really. when i build engines i use weldseal to seal everything on engines rather than a silicone sealant apart from sumps i always seal sumps with a quite alot of silicone sealant as i know how much of a fucker they can be. weldseal only requires the tiniest amount to seal alot.