I'm sure this has been discussed on the forum before, but I can't find the relevant post.

Should a head gasket be fitted with the rolled edges on top or underneath, or does it matter?

Thanks
John

Location: Flat Norfolk

Hello John,
I was always told to fit a head gasket rolled edges down, but for the life of me I don't know why!
J

Location: As far east in Kent as you can get

Given that it is to be clamped between two supposedly flat pieces of cast iron, what possible difference can it make??

Ian Mc.

Location: Shropshire

I was going to say UP but I thought I would see what Woodrow says "Crimped side down" . I think Ian as the right idea.

Location: Oakley ,Hants

Interestingly, a couple of old magazine articles on the Cornwall A7 site, and a 1950s copy of The Motor Repair Manual make no mention of which way up, but a new gasket that I have has the writing on the face with the folded up edges implying that this should be put on with the edges uppermost, i.e. next to the head.
Personally, I'm with Ian; what difference could it make?

Location: Near M1 Jtn 28

The reasoning behind having the rolled section uppermost is if there is any Fretting ie movement between head and block,it is much more easily repaired on the head than the Block.
This generally applys to most Head Gaskets

Hi John.

My Austin handbook 1316A says the side stamped "Austin Cooper Gasket" should be downward.

Pitman's says "If the original gasket is used again, see that the marked side is uppermost".

Nicholson (always good for a smile) insists on calling it a "joint washer", which should be "metal face downwards".

So take your pick.

I wonder if the smooth side up / rolled side down advice for Copper/Asbestos type gaskets applies to OHV engines with wet liners, where the pressure of the liner top might give a better seal onto the rolled edge ? Perhaps this advice has expanded beyond its original application.

For the A7 engine I can't see any reason why it matters which way it goes

John Cornforth

Location: New Forest

I think a thin smear of Loctite goo and tightening down the head correctly is the most important thing.

Payens told me that you put the printed (crimped) side upwards. Don't think you can argue with that!

David

When I did my apprenticeship, I was told crimped side up.
Done that all my life.

Location: Wet and windy Wales

I believe Ian has the right idea in that it makes no difference, although I was told by many experienced mechanics it's crimped side up. Perhaps they were used to more modern engines where the cyl. head could be softer, especially aluminium? Incidentally, John Cornforth is correct in quoting a 1935 H'book (says crimped side down), but most earlier H'books say copper side down. A change of policy, or yet another Handbook error? Cheers, Bill in Oz

Apologies, but left a bit out of above. The May 1936 H'book makes it clear what Austin required. It not only says "beaded edges upwards", but includes a drawing which makes it doubly clear, with similar caption. Probably all academic? Cheers again, Bill in Oz

And to add to the confusion- Austin 7 Handbooks 1400B and 1400D both show 'Replace the Gasket beaded edges downwards'

Tony.

Thanks Tony. I had a memory of a discrepancy, but at the time couldn't locate the two H'books to which you referred. Have now found them, can confirm more confusion. Cheers, Bill

Thanks to all for suggestions.

Need to stock up with "coppaslip" before re-assembly and also investigate the Ruby's leaking radiator drain tap

John

Location: Flat Norfolk, (crimped side down)

Location: Shropshire

Thanks for clarifying that, Ian. I can never remember numbers! It is available at Halfords and is invaluable. It seems to be particularly good on cylinder heads and importantly is easy to remove.
When fitting a cylinder head I always run a drill through the stud holes to remove any rust or crud. I like the head to be able to lower onto the block without any difficulty. In some cases I have opened out the stud holes by a 64th inch to compensate for slightly misaligned studs.

I can agree with the stud clearing message, worth also checking that the nuts actually are tightening down onto the head. I had an engine a few years ago that would blow head gaskets quite regularly (15k miles from memory?). I fitted another head, which made the problem a bit worse, so I had it skimmed and it was much worse. Eventually, I found that the nuts were bottoming on the (old) head studs and not quite tightening the head down. The replacement head was probably a bit thinner, hence it aggravated the problem, which was made critical by the skimming operation.

Had to replace all the head studs (there's another story), after which...no further problems.

BTW, crimp side up for me!

Location: North Wiltshire

Thick hardened washers Allen makes nice ones

I've just replaced a head gasket and now find that two of the nuts won't tighten properly, probably because the stud is moving in the block. All the other nuts tighten to the correct amount using a torque wrench. Do you think I can get away with this?

Location: South Shropshire

Hello Robin,
In a word no!
Even if it doesn't leek it will let go eventually, get it right now and you won't have to
worry about it later.
J

Location: As far east in Kent as you can get

The moral of all this is that when you tighten the head nuts, it is important that you are actually tightening the head down. There is no use tightening a nut to the recommended torque if it is bottoming on the thread or acting on a bent stud.

If the head has not been checked for loose debris it may decide to deposit it's rusty contents all over the place as you fit it.

Just an observation. Hope it's not just teaching Granny...

As it happens, I am with those who put the gasket crimped side up for the reason given that any damage caused by fretting is easier repaired if found on the head. How relevant this is in reality, I don't know.

Location: Derby