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By Conny
#87333
I have always had a problem with blowing head gaskets on my Constellation. I am using the standard copper gaskets. The heads are true and nuts correctly torqued.

What sealant do other owners use and any suggestions?
Thanks
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By Presto
#87334
Have you considered using the composite type gasket? With problem engines these are often a better option than the solid type.

I don’t think the gasket compound is that vital. Wellseal is one regular choice.
By Jools G
#87335
Blowing head gaskets on Constellations are a feature! Nevertheless, there are ways to avoid the problem.
It goes without saying that you check the heads AND barrels for warpage/damage before fitting the gaskets. Lap them both on plate glass if necessary to achieve the correct flat surfaces.

1). Don't use the 'thin' type of copper head gasket (around .012" thickness). Whilst this gives the correct compression ratio, they're simply not good enough (especially the c**p ones found in modern gasket sets); use the Super Meteor type instead (around .025").
2). If you're using copper gaskets, anneal them before use (heat to cherry red and plunge into cold water).
3). When torquing down the heads, ensure that the 2 inner nuts are tightened down first, i.e. don't use the traditional 'diagonal sequence'; this may seem counter-intuitive, but is in fact the method suggested by RE themselves.
4). Run the engine up to get it warm, shut it down and allow it to go cold. Re-torque the head nuts. Ride gently for the first 50 miles and then re-torque again (don't forget to check the valve clearances at the same time).

As has been suggested, you could try the composite type, though I've never needed them myself (and I believe they're quite expensive too!).
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By Conny
#87348
Thanks for the replies. I have been using the thicker head gaskets and have done most of what Jools has said other than a 3rd tighten. What are the composite gaskets? If it helps solves the problem an extra cost (within reason) is immaterial.
By Jools G
#87350
I believe that the composite type are made from high-temperature-resistant reinforced gasket 'paper' which is fitted with a flame-proof ring of copper shim at the combustion chamber interface - not the best description I'll admit, but about as close as I can get!

Many years ago, I spoke to (Andy Hunt?) who used to race a Super Meteor outfit in classic racing (maybe he still does?). I mentioned the head gasket problem and he was the first person I'd met who was using the composite type; he told me that it had cured the problem, though expensive at £14 each in those days.

The composite type are far more compressible than the copper types, and are thus rather more adept at conforming to any irregularities I imagine . If they can withstand racing conditions, they certainly ought to be able to cope with road use.

I've always used 18ft/lbs as my torque value, though I believe that the RE recommended value is higher at 22ft/lbs. Having seen the crushed alloy on the inner 2 cylinder head stud holes on several on my spare heads, I'm a bit reluctant to use more than 18lbs.
By Jools G
#87351
As this forum doesn't allow editing of posts (even though it's supposed to), here's something I meant to add, so apologies for the ommission;

Composite head gaskets (x 1 pair) part no. 38636A - available from our hosts.
By Marko
#87356
Hi, on my Connie i'm using the thicker copper Meteor head gaskets which I annealed. As for "sealant" I've used a product called "heldite"; its similar to wellseal only much better. I did the job last summer & touch wood so far so good ;)

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