27 replies to this topic

[lionmod_boy]

Removed my head for the first time today as lost compression on 2&3. Head gasket failure (fibre gasket??). Anyways i was just wondering what is the prefered methothods of cleaning the pistons without removal an without any crap going down and damaging seals and also am i best changing the bolts?

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Edited by lionmod_boy, 25 June 2011 - 06:23 PM.

[bmcecosse]

My view - don't clean the pistons - leave well alone. DO clean the top of the block very well - without marking it in any way. Check the studs are firmly in the block - clean the head carefully and grind in all the valves of course. Refit with a lick of grease on both faces of the gasket and torque it to 44 ft lbf. Set the rocker gaps and it should be fine. Retorque after the first heat cycle!

[lionmod_boy]

all i am worried about not too visable in the pics but on the piston closest to where the heater valve is there is some ... the best i can describe it is like limescale in the bottom of a kettle on the top of it. should i oil the pistons? I have removed the studs from the block. Will the grease not heat and melt leaving a gap? or does this help to seal it?

Thanks for the advice really appriciate it. hope i am doing everything right. should i use solvent to clean block surface?

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Edited by lionmod_boy, 25 June 2011 - 06:38 PM.

[MiniLandy]

Refit with a lick of grease on both faces of the gasket...

...don't do that.

Your pistons actually look pretty good, the light brown colour indicates a correct mixture. Clean the mating faces (the top of the block and the bit of the head that it mates to) very well, being careful not to scratch or gouge them. A flat blade is best, i use a steel rule. Pay attention the clean up the head studs too, unless they're warped or bent you won't need new ones.

Make sure the mating faces and the NEW headgasket are free of any oils or grease, and place the headgasket, and then the head, in place. Put a SMALL drop of oil on the threads of the head nuts for when you torque them up. Torque them in the correct order, and as BMC said, torque them again after a heat cycle.

WD40's fine for cleaning up the mating faces, but make sure you wipe away all traces of this before reassembly, with a clean bit of kitchem roll or the like.

Don't oil the pistons.

Edited by MiniLandy, 25 June 2011 - 10:58 PM.

[bmcecosse]

I firmly believe in a lick of grease - have always done this and never had a problem, on some pretty lairy engines too! But you takes your chances....... The retorque should be after the FIRST heat cycle.

[Cooperman]

I firmly believe in a lick of grease - have always done this and never had a problem, on some pretty lairy engines too! But you takes your chances....... The retorque should be after the FIRST heat cycle.

Always lightly grease or lightly oil the copper-faced gaskets, but never grease the BK450 'black' gasket as it must be installed dry.
Never use those fibre gaskets if you want the gasket to last.

[MiniLandy]

I firmly believe in a lick of grease - have always done this and never had a problem, on some pretty lairy engines too! But you takes your chances....... The retorque should be after the FIRST heat cycle.

Fair enough, but the Haynes manual and everyone else i've spoken to on the subject, heartily disagree.

As for the heat cycle, you're quite right. I usually retorque mine a few times, after each cycle, but that's just because i'm paranoid. I'll edit my earlier post.

[bmcecosse]

Yes - copper face gasket every time.... If you believe in Haynes - do you also believe in Fairies ???

[nordicmini]

LM grease high melting never had a problem use on all gasget

[liam1288]

how did you get the head off without reoving the exhaust manifold completely? when i did mine i had to to get enough room...i was following haynes though. it was a bugger to get off and back on! if id have known you could leave it on wouldve saved ages! lol thinking of changing my head so please do tell

[jaydee]

A friend of mine who worked at rover for a long time told me it was standard procedure to fit copper gaskets WET.
(Fibre and composite gaskets always dry)

[1984mini25]

how did you get the head off without reoving the exhaust manifold completely? when i did mine i had to to get enough room...i was following haynes though. it was a bugger to get off and back on! if id have known you could leave it on wouldve saved ages! lol thinking of changing my head so please do tell

Simples, remove the bolt in the bottom engine steady near the sumps drain plug, then the two top ones on the steady on left hand side of the block and then under the mini remove the bolt for the manifold to diff.

That way with both the steadies and the exhaust manifold free from the engine, you can then rock it on the engine mounts.

Or if it’s a standard mini with the cast all in one inlet and exhaust manifold. I’ve always just undone the down pipe clamp, disconnected the fuel pipes and cables and lifted the head off with all the manifold and carb still attached.

[lionmod_boy]

how did you get the head off without reoving the exhaust manifold completely? when i did mine i had to to get enough room...i was following haynes though. it was a bugger to get off and back on! if id have known you could leave it on wouldve saved ages! lol thinking of changing my head so please do tell

I removed the studs... couldnt get the space to get over the studs so removed them.


I have ordered a copper gasket... dont know much on the gasket side maybe i should have got the bk 450??

Any advice on what the copper gaskets are like? place i ordered it sais they are good even with performance mods.

[lionmod_boy]

I have ordered a copper gasket... dont know much on the gasket side maybe i should have got the bk 450??

Any advice on what the copper gaskets are like? place i ordered it sais they are good even with performance mods.

[Retro_10s]

Of all the headgaskets I have ever used, copper, fibre and the payen type, I have had the same experience with all them.

I install them dry (That's not to say that putting the copper ones on wet isn't fine, I've just never done or heard that before) making sure the mating surfaces on the block and the head are spotless, straight and Dry. Then torqued up in 3 steps (the third round of tightening being the final torque down) Set valve clearances.

Then let the engine come up to temperature, then let it go stone cold again, And finally Re-torque the head bolts.

Never had one go yet

Could someone expand on the the 'grease helps' theory? A manufacturers recommendation or something of the like?