Which head gasket set?

[JJDraper]

Why bother with all this technical stuff? What you all need is this...

Says it works in 99% of the time or your money back! No tools required (apart from the punter).



Jeremy

[el-saturn]

my highest measurement was/is 0.0015" = 0,038mm - the gasket is 1,2 thick an you compress to 1,0 sandy

[69S4]

Why bother with all this technical stuff? What you all need is this...

IMG_20190613_123615074.jpg

Says it works in 99% of the time or your money back! No tools required (apart from the punter).



Jeremy

I seem to remember from way back another snake oil product, a kind of paste that you squirted down the plug hole and it fixed a worn bore. Can't remember its name but a tube of that plus the head gasket stuff and the engine'd be perfect. No need for rebores or stripdowns.

Confession time - I actually bought some of the worn bore stuff when my Lambretta started losing compression. In my defence I was only 16 at the time and it was heavily marketed but, as the Specials sang, "it did nothing for me". (What it actually needed was a new set of rings)

[JonB]

Well this is all very interesting but I seem to be no closer to a definitive answer.

I do want to use an Ajusa gasket but I'm worried that the minimum size is, well, a bit too big. So I will end up with a "standard" copper gasket as we see in the Burtons catalogue. I recall that Miles says one should spread Wellseal on both sides before fitting, presumably like butter (awful messy job). What say you all?

[2cams70]

Well this is all very interesting but I seem to be no closer to a definitive answer.I do want to use an Ajusa gasket but I'm worried that the minimum size is, well, a bit too big. So I will end up with a "standard" copper gasket as we see in the Burtons catalogue. I recall that Miles says one should spread Wellseal on both sides before fitting, presumably like butter (awful messy job). What say you all?

I used a gasket from HJ in my engine. Small one man band making custom gaskets here in Australia but I think he's still in business. Topic has been discussed before:

viewtopic.php?f=15&t=15593&start=

Some good information about LTC history in the Miles book but some of the rebuild information is a bit out of date especially with regards to use of sealants. I think he has shares in Dow Corning. Use of sealants in a lot of situations is for "psychological benefit only" and can be detrimental. A good quality gasket material and having even level flanges are more important.

[lotusfan]

I have resurrected this thread because it may be relavent to my current issue.

When I recently took the toy out of hibernation I had to add about a pint of coolant which was puzzling because there was no puddle underneath. Engine oil appeared the usual black on the dipstick. Took it for a short run to warm the oil for an oil change and when I drained the oil it was brown, not black. Closer inspection showed mayonaise on the underside of the oil filler cap. Conclusion was that there was water in the engine oil and probably caused by a head gasket leak.

Having removed the head there were no obvious signs of leakage, the fire rings were good but maybe a suspicion of a coolant leak to a head bolt hole. A compression test a few hundred miles ago showed around 200 psi on all cylinders.

The head gasket that had been used was the original copper/steel type and reading this thread the recommendation is to use the Ajusta composite type which I will use in the rebuild. There is reference in this thread to coolant leaks being fixed by using the Ajusta gaskets but no indication of where the coolant leaks were.

So, since I have not found any solid evidence of coolant leakage I was intending to try and pressure test the block, it's still in the car and I would rather not remove it but if there is water pump leakage I will have to. I will also try and pressure test the head.

What other investigations should I do before I start the rebuild? I am concerned that I may not yet have found the cause.

[alanr]

In discussion with QED recently on the question of which head gasket to use on my Std bore engine their view was that an Ajusa gasket will not seal any better than a Payen copper one and it is just a question of choosing the right size gasket to use with the right size bore always assuming that the head itself is prefectly flat in all planes.
They have greater recent experience and knowledge than I have so bought the copper one. Time will tell I guess.

Alan.

[Pfreen]

When I rebuilt my tc, (.02” oversize), I ordered a head gasket from RD. When I got around to installing it, it measured something like .055” thick. I don’t know the Manufacturer. I had cc’d the head and carefully adjusted the chamber volumes to give a 10.3:1 cr in each chamber. This requires the original head gasket (Payen) which crushes to I believe 0.025”. The .055” head gasket would have reduced the cr to 9.5:1. RD did not carry the original copper/steel Payen gasket then. I then ordered a .030” thick Cometic gasket. The holes did not line up very well with the block and head. I sent it back. I then found that Dave Bean still sold the original Payen gasket. I put that in and it works fine. I have never had a head gasket problem on my Stromberg engine in the 34 years I have owned it. I think I have pulled the head four times in that time and always fitted the Payen gasket.

[JonB]

I used a bog standard copper gasket with Wellseal per St Wilkins and had zero problems.

[lotusfan]

Alan, Pfreen and Jon

Thank you for your comments, you all say use the standard copper/steel gasket. I have to fess up to not having retorqued the head bolts at 500 miles so may be mea culpa.