Replacing cylinderhead

[Paul Nott]

Thanks for the advise, the vehicle prior to me purchasing 14 months ago had been standing for a number of years.
Since then I've added around 500 trouble free miles in between a long list of repairs or improvements, the cylinder head was one of the last jobs to do (although the list has a tendency to grow).
I'm also in the process of replacing the various bulbs to L E D- a great improvement, have a mad idea of competing in next years Measham rally if I ever get it finished !
The head was supplied by Dave Dye, haven't ordered the gasket as yet but was going to order a Ricardo unless anyone knows better.
Tempted to decoke and rebuild and wait and see how she performs .

[Alan]

The thing is, if it’s done 500 trouble free miles, it’s probably going to do a good few more. If you pull it apart and rebuild it it’s going to cost and may not achieve much in the way of increased reliability. Unless you have a burning need to work on engines remember that a new crank, rods and pistons with the block bored to suit will cost you over 2 grand. Like I said, if it’s not broke .......

[Davemayle]

I would agree with the above Paul but having just done the same with mine I would take a good look at the threads on the head studs. A pain to change and can cause tears before bedtime, but a real pain when they give out fitting the new head. I noticed one in the picture that looked liked mine!

[Ian Williams]

Those marks are typical in a seven engine that has a seeping head gasket which was been allowing water into the bores, sadly all too common with modern head gaskets. With regular use they do often seal, however the problem seems to come when they just get the occasional short run after a gasket replacement, especially when surfaces and water transfer holes are not in perfect condition. I have said it before but my belief is that the modern asbestos replacement used in current gasket manufacture is too hard for our modest torque settings.

[Bob Culver]

On my own car over the decades the traditional cu asbestos head gasket was  reused repeatedly and no apparent leakage. Old books like Nicholson assume re usage. Similarly on a Javelin car I ran for 20 years and which involved very many head removals.  (Although on both cars gasket did not remain bright cu all over.) Many Javelins were originally prone to gasket problems because of settled liners but the problem has recently re emerged significantly despite rigid seals (seriously compromising the reliability of the vehcles). As per Ian, the modern gasket material seems to be the common weakness. Also the fact that single sided gaskets cannot be reused represents a significant cost.
The users are mostly little fish and the chain of manufacture and supply is tenuous so any feedback may not get far. Would expect in this day and age something reliable to be producable.

[Colin Wilks]

A couple of years ago the availability of HC gaskets was not good. I approached a local firm (Dobsons Gaskets in Keighley) to get a price for making a solid copper item as a one off or short run. I cannot recall the price now, but it was not silly. Ian, what is your ideal spec for a gasket please? If it is solid copper, which can be annealed as necessary, I imagine many people might be interested in paying the same or a bit more for a reusable item.

[JonE]

I'm presuming, having now been given an original new 1940s HG so I can SEE/feel the difference in materials, that if modern HGs are now essentially seen as single use for safety, then that suggests that the coppersilicone type sealant becomes a necessity on unrestored engines. When I used the coppersealant, it just seemed something which meant it was more difficult to get the HG off when you had to do a head removal - but it seemed from feedback that people didn't seem to decoke anymore with modern fuels.

[Ian Williams]

I have used solid copper gaskets but don't think they are the answer for the average seven, they handle high compressions and on a dry decked racing block would be good but they are very difficult to seal if you have water ways passing through. I never had a problem with old stock gaskets when I first started playing around with sevens as a 19 year old, now almost 40 years later I see a lot of engines where the gasket has been seeping. The old copper asbestos gaskets compressed much more than the current product and as I said earlier this is I believe the issue.

[Chris KC]

To rebuild or not rebuild is a difficult question. I'm inclined to agree with Alan that something running well is best left alone.
But on an 'unknown' engine I want to get inside and see that everything is in order. They are at their best when they have been running dependably for several thousand miles and a rebuild takes you back to square one again.

[Paul Nott]

Just getting ready to fit my new alloy head and was wondering if the headgasket should be coated with grease or gasket sealer prior to fitting.
What do you use on a modern copper gasket?