Re occurring head gasket failure - ideas?

[super trimbo]

Just been through mg third h gasket set in as many months, head has been skimmed ans always been put back as per Haynes manual instructions. Any ideas why this keeps happening ?

[autolycus]

How flat is the surface of the block?

What re-torquing regime have you followed each time?

Has the engine overheated since the head was last skimmed?

Kevin

[lambrettalad]

does it always blow in the same place? Which replacement gaskets are you using? recent or old problem?

[bmcecosse]

What engine is it? And as above - where does it blow. Are nyou using a torque wrench - and are you syre the calibration is reasonably correct? Be sure to get a COPPER gasket - local Autoparts place usually has them for a few £s. No need to buy a gasket set!!

[super trimbo]

In reply to the posts so far:

- The block itself is free from pitting but I have no idea if it's true along the length of its surface
- Head has been skimmed
- Always blows between 2 and 3
- Torqued down to 55 ft lbs, in the order mentioned as per haynes manual

It's totally doing my head (excuse the pun) in now.

[bmcecosse]

I guess the block is erroded then between 2 and 3 - due to being run with blown gasket. It is ESSENTIAL to switch off immediately if/when the gasket blows.. Remove the studs and clean it all thoroughly - then use a steel rule on edge with a light source behind to see if the block is flat. If not - it's a complete engine strip down to bare block - to get it skimmed flat.

[lambrettalad]

do you retighten after first heat cycle ?

[IslipMinor]

55 ft lb is much too high for standard studs - they could be stretching and not clamping properly.

What studs are you using? If they are standard they should be replaced and torqued to standard settings - 40 ft lb or a maximum of 44 ft lb.,