copper headgasket

[chrisgriffiths]

Hi everyone
I'm in the process of renewing the headgasket on Mable. I've bought a copper gasket and I just want to know if it makes any difference which way up it goes on the block. One side is copper and the other is black on the gasket
Cheers
Chris

[bmcecosse]

I would fit it copper to head - thin wipe of grease over the faces. A 'real' copper gasket is copper on both faces....... Spotlessly clean surfaces - but don't use emery paper or anything like that..

[chrisgriffiths]

OK cheers
Is the grease just to hold it in place while fitting

[bmcecosse]

Helps it seal down - and stops it sticking when next it is next removed!

[IslipMinor]

Does the gasket have 'TOP' on either side of it?

[philthehill]

As bmc says do not use emery paper on the cylinder head of block faces.
The best material to use is a Heavy Duty 'Scotch Brite' scouring pad. Removes the crud without scratching the surface.
They are also good for removing the staining from lathe beds and other machinery with bright surfaces.
As regards head gasket marking they are usually marked 'TOP' & 'FRONT'. If not marked 'TOP' it usually means that they can be fitted either way up. Of course they can only be fitted one way round as the gasket is not asymmetrical i.e. the push rod holes are only on one side of the engine.
Again as bmc says grease the gasket faces to help bed the gasket in and to assist when removing the head in the future. Also grease the stems of the cylinder head studs but not the threads as that may allow over tightening. Unless specified threads should be torqued up dry.

[les]

I use emery paper on iron/steel but not aluminium why do you think this is wrong?

[philthehill]

les
To answer your question - if you use emery paper/cloth on the cylinder head/block gasket faces and it is a course grade and the user is enthusiastic in its use a low spot could be created which could lead to water loss or gasket failure; also lines could be created on the gasket faces again leading to water loss or gasket failure. So to me using emery paper/cloth on the head gasket faces is a no no.
As an aside emery paste/granules could get into the bores and that is not desirable.
The above does not mean that there is not a place for using emery paper/cloth in certain circumstances. If I have to clean/true up a gasket face and it is small enough to fit on my surface plate (a sheet of glass can be used instead) I will put a piece of emery paper (grade dependent upon application) on the plate and use the surface plate to maintain a true flat surface.
Phil

[les]

Ah, see what you mean, I thought you might have had a concern with the paper itself. I use a surface plate with a sheet of emery on it, or a large block, to avoid dips.

[bmcecosse]

Yes - as above -as long as the 'abrasive' paper is full supported by a flat surface - no harm is done. The problem comes if someone has a lump of paper in their hand and rubs away at the head - usually the narrow lands between the chambers - they wear a low spot - and then wonder why the gasket blows........ I tend to use a large flat file gently rubbed over the surface and held down absolutely flat on the surface. The aim really is to highlight any 'high' or 'low' spots for further investigation.