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Head Gasket - Best Practices

mjobrien

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OK, So I'm going to have to reattach the Head now that the Valves guides have been inspected and redone.

Any advice or best practices on making sure the Head Gasket seals?

Thanks,
Michael.
 
I used some Permatex copper spray gasket sealer, which you should be able to get at pretty much any auto parts store, when I put my head on my 100, I know I had the head of at least three times, never any problems.

I told a car buddy this and he said that product was "old school" don't know if he was teasing or if in fact something newer and better has come along?
 
Assuming you are talking about the Hundred Four. The headbolt pattern/spacing is not ideal under the best of circumstances.

I have used the copper-asbestos-copper sandwich gaskets plus copper sealer, with "near" success. When I pulled the head after a couple of years running there were signs of beginning leakage between cylinders. No actual measurable compression changes yet. This with the DWR high tensile head studs, & hardened washers. Continued running would have resulted in progressive failure.

Looking for a better solution, I used the DWR multi layer steel gasket. This gasket is the latest technology & works very well on difficult to seal engines such as the Four. Again with the DWR head studs & hardened washers. I have checked bolt torque several times, no changes from original. Absolutely NO coolant, oil, or compression leaks.

A quote on MLS gaskets,
-----MLS head gaskets are made of several layers of embossed stainless steel. A thin coating (0.001- to 0.0015-inch) of nitrile rubber or Viton is used on the external surfaces as well as between the layers to provide maximum sealing. MLS gaskets are almost bullet-proof - but also more expensive than conventional soft-faced gaskets. Even so, if you want to fix the problem once and for all, MLS is the way to go in this application.

Requires a smooth surface finish. 20 RA. Very smooth. Head & block flat to less than .002".------

The theory is that the mating parts always move a bit with expansion-contraction of the parts. The MLS permits this slight movement without compromising the seal. A rougher surface finish would bite into the gasket surfaces & prevent part of this movement.

The standard procedures for installation should be followed.
1- Clean all stud threaded holes with a tap.
2- Countersink/chamfer threaded block holes to prevent lifting the top thread
3- Use sealer on all stud threads that extend into water or oil passages
4- Install studs into block only finger tight, not torqued
5- Use lubrication on the top stud threads & washers, torque to 75 lb/ft in stages
6- Loosen & re-torque several times before final tightening to bed & smooth the threads into the mating surfaces.

You might get by with compromises along the way & maybe not. Why take the chance.

I guess you already know about the rocker oil feed stand to shaft pre-alignment before assembly.
D
 
I too will vouch for the MLS head gasket, though I haven't needed one yet for my Healey 6-cylinder engine(s).

I was having trouble with my supercharged M Rdstr pressurizing the cooling system. Compression & leak-down tests would all yield xlnt results, but the problem persisted (including trace amounts of sodium in the oil analysis samples).

I pulled the head and had it resurfaced for the MLS gskt, installed ARP head studs (cycled like Dave's DWR studs) and haven't over-pressured my cooling system since.

Use no sealants on the mating surfaces of an MLS gskt; clean & dry. Exceptions being a dab of sealant at the mating joint of the block/timing case.
 
I noticed that denis Welch sells these MLS gaskets, any other stateside sources?

Thanks,
Michael.
 
No other sources that I know of. There is so little call for such gaskets, that DW likely had a special run of them made. I certainly won't fit much else except a few A90's. There could be another UK source but I doubt it would be any cheaper.

The price IS outrageous but they certainly do the job.
D
 
I believe a company called "Cometic Gaskets" in the midwest of the usa makes these to order, maybe a bulk order from forum people might work pricewise
 
Dave Russell said:
No other sources that I know of. There is so little call for such gaskets, that DW likely had a special run of them made. I certainly won't fit much else except a few A90's. There could be another UK source but I doubt it would be any cheaper.

The price IS outrageous but they certainly do the job.
D
I pay just a tick under $200.00 for a BMW 6-cyl MLS gskt, and you know how many of those engines are in circulation!

The same BMW gskt is available in a range of bore diameters to cover 2.0 to 3.2 Ltr engines, and thicknesses from .070" (stock) to .140" for cut heads to turbo/supercharger applications.
 
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