18 replies to this topic

[bobbym18]

Hi all,

I've asked a lot of questions recently about leaks and rough running etc.
I've come to the conclusion that I don't think my new copper head gasket is sitting or sealed correctly.

Firstly there's quite a bit of debate on here about which way up the gasket should go, mines a copper one from mini sport, so it should be copper side up? Right?

And I took my dad's advice and didn't put any gasket sealant on the head gasket, is this correct? If not what sealant should I use?

Thanks

Rob

[RooBoonix]

No sealant is correct, and I think Copper up is right too.. What makes you thing it's not seated properly?


Cam.

[bobbym18]

Well there's a small amount of leaking around the edge of the gasket, the little bit sticking out around the front of the head. At first it was water and now oil too.

I've read somewhere else that a sealant should be used?

[jime17]

Have you re-torqued the head nuts after 1 heat cycle?

[sonikk4]

There seems to be a bit of an issue with certain HGs, I had exactly the same problem. It did run ok still seeped fluids. Changed it over to a Payen gasket and problem solved.

The first gasket was torqued correctly on initial build and after one full heat cycle. Cylinder head face was flat and true and so was was the block deck.

[bobbym18]

I have had it running and retorqued but it's still leaking a bit.
would you recommend getting a new gasket?

[Mad Max]

I personally had horrible problems with copper head gaskets. Always used the composite ones since, recommend payen, not had a problem with these

[Spider]

Copper Head Gaskets are great BUT only if the Head and Block Decks are dead set perfect, polished, otherwise you'll be sorry you ever saw a Copper Head Gasket!

 

They are a bit harder than most other gaskets out there, and as they are harder, they don't conform well to regularities.

 

If the preparation is right, they stand up to heat and high combustion pressures better than any other gasket as well as better equalising the mating face temps between the head and block, and so will move less in service, making them more reliable.

 

Unless your Block and head have been fresh ground finished or at the very least Oil Stoned, fit a softer Gasket.

[bobbym18]

right i think i will treat myself to a payen gasket then. And its definitly no type of sealant on the gasket?

[jaydee]

Do not put any sealant, theres already a sealing compound over peyen gaskets.

Use a BK450 peyen gasket if engine is a 1275. If small bore either a rover or a peyen copper gasket will be fine.

Make sure block deck and head surface are spotless prior to fitting, in most cases a stone rub or even a clean up with grit (beware this require a bit of experience), followed by a good rub with thinner and rag is necessary.

Use tap water for first houndreds of miles, coolant wont allow the gasket to seal if leaks during the firsts miles.

[bobbym18]

ok nice one, i havent heard about the coolant being a problem before, maybe that hasn't helped then

[racingbob]

on the payen gasket 460 copper I was told to put
smear grease which seemed ok this was on race mini in the 90's

but yes the bk450 seems to be the one to use 1275

[bobbym18]

My engine is only 998, I was going to go for the black fibre performance gasket on mini spares

[bobbym18]

My engine is only 998, I was going to go for the black fibre performance gasket on mini spares

[jaydee]

The 'fit it wet' trick was to allow it to move in place when you put the head on and it slightly moves while doing the bolts, I now fit copper gaskets absoletely DRY and never had a problem with this.

Honestly i'd rather check the studs are true and that the gasket falls down without catching on them, that may give an indication of a possible failure once you fit the head and torque down the bolts

Also dont be tempted to over-do the head bolts, i know someone says 'it leaks, do the bolts tighter', thats totally hopeless unless you want to snap a stud or (if you're lucky to not snap it before) to remove the stud on from the head exactly like you were undoing it the two nuts way.