A quick YSE12 question........

[Scaffi S28]

When I took the head off my YSE12 a few months back, it was a major battle involving chisels and a heavy lump hammer. There was very severe rust between the studs and the head, which was the main problem, but also the head itself was firmly rusted onto the block despite the presence of a standard head gasket.

So I'm now at the re-assembly stage, and my plan, to avoid the same thing happening to the next unfortunate sod to pull the head off (hopefully not me !) is to apply silver anti-sieze grease to the studs in the hope that it'll prevent a new corrosion growth.

My question is: it is a good idea to apply some kind of grease to the face of the head and the block (i.e. either side of the head gasket) I have a vague recollection of greasing head gaskets on car engines somewhere in the dim dark past, where there's been cast iron head on a cast iron block.....

Any thoughts on the subject ?

Cheers,

Martin

[jimbunyard]

No grease or sealant on the sealing surfaces, the manual says nothing about oiling the threads of the head bolts, which I would take to mean not to oil them. In practice, I would chase the threads in the block with the appropriate size bottom tap, clean and lightly oil the head bolts, and use some type of 'never seize' on the part of the bolt in the head, and tighten to 12.4 Kg/m. For studs, same thing except for use of a die on the threaded part of the stud. Don't put much on the shaft of the stud, because when you put the head over them, it will push a clump of it down between the head and the block on top of the head gasket, which could cause sealing problems later on. If it were me and I could get the studs out I would remove them all, clean them up, and when reinstalling the head put two in dry temporarily to align the head and the gasket, and then neverseize (or whatever) the other two and install them, remove the ones used for alignment and never seize and install them, then tighten the head nuts to 12.4. Detroit used to have something called (I think) International Compound #2 specifically for this, but I don't know if they still do or if it is available in a non-proprietary form.


Lot easier to do it than to write it down...

[Scaffi S28]

Thanks Jim,
I think if you saw how crap the access was to the engine in my boat, you wouldn't be saying "easier to do than to write down"........ :-) It's a flippin' nightmare of bodily contortion just to see the studs, let along run a die over them !

But I'll see what I can do to clean up the studs (and of course the mating surface of the block which is probably as pokmarked and corroded as was the head before it was skimmed) I've heard that there's a Hylomar sprayon stuff for headgaskets in situations where the surface is less than ideal. Perhaps I'll chase up some of that. With the diesel being such high compresion, it'd be disappointing to have the head gasket leak.

Cheers,

Martin

[shakey doug]

Have been using very dense silver paint on block head decks showing signs of corrosion for 45 years some may need a couple of applications.

[Scaffi S28]

Originally Posted by shakey doug

Have been using very dense silver paint on block head decks showing signs of corrosion for 45 years some may need a couple of applications.

Hi Doug,
What sort of silver paint are you talking about ? And do you mean using it on the joint between the head gasket surface on the block ?

And what do you mean about some needing a couple of applications ? Do you mean the head has to come off again to re-do it ?
Thanks,
Martin

[jimbunyard]

Sorry, I should have said 'if you have the engine out and on a bench or stand, then it's easier done than written'. I wish I had the confidence(?) of these designers/builders in the capabilities of their designated product selections...


Anyway, 45 years ago I was 11, and so missed out on the silver paint fix for pitted sealing surfaces. I looked at all the non-hardening sealants on the Hylomar website and didn't see any specifically listed for this application. Can you advise which you were considering?


A normal head gasket has a reasonable amount of gap filling ability on its own. If you've had the head shaved it should be flat, and if you get all the old gasket and rust off the block, paying close attention to the area around the studs, the head gasket itself normally does a good job of sealing without any need of additional sealant or gap filling products.


It is more important to have all the studs in the same condition (hence the suggestion of running a die down the threads), so that when you torque the head down the clamping pressure is evenly distributed. If the clamping pressure is uneven, it will eventually lead to leaks.

[sfnz]

Originally Posted by Scaffi S28

When I took the head off my YSE12 a few months back, it was a major battle involving chisels and a heavy lump hammer. There was very severe rust between the studs and the head, which was the main problem, but also the head itself was firmly rusted onto the block despite the presence of a standard head gasket.

So I'm now at the re-assembly stage, and my plan, to avoid the same thing happening to the next unfortunate sod to pull the head off (hopefully not me !) is to apply silver anti-sieze grease to the studs in the hope that it'll prevent a new corrosion growth.

My question is: it is a good idea to apply some kind of grease to the face of the head and the block (i.e. either side of the head gasket) I have a vague recollection of greasing head gaskets on car engines somewhere in the dim dark past, where there's been cast iron head on a cast iron block.....

Any thoughts on the subject ?

Cheers,

Martin

Lanacote is your friend here, actually you've got 2 head studs and 2 long head bolts on these, pull em out and clean threads etc etc ( bench mounted grinder with wire brush wheel) Coat all in lanacoat and reassemble, torque, run and retorque. To get the head studs out you'll need both nuts on the same stud as a lock nut setup, replace if rust/ pitting is excessive