Head Nuts on 1963 Mark 2

Hi all, l am looking to replace the rusty head nuts on my 1963 2.4 Jaguar Mark 2 Saloon. I was going to replace them one at a time with new Chrome nuts. If I tension each nut down to 54lbs as per the service manual, will i run into any problems that you can think of? By doing one at a time, will that in anyway cause me a problem with the head gasket?

I have done that with no problems, but I ensured they were all correctly tensioned before I started . The alternative is to remove all of them in sequence and fit the new set and retension in sequence, but I would do one at a time.

I had a problem with some of the replacement nuts in that the threads were not cut deep enough and though they gripped the washer, they bottomed on the studs before coming to tension on the head. The tension wrench tripped of course, but it was a false indication. I picked up the fault before starting the engine.

Run all the nuts down without the washers to check for thorough travel. Run a bottom tap down to cut the thread deeper where necessary and make sure they are free running by hand all the way.

For extended layup parking, I smear a coating of light grease on these parts and wipe it off before rolling out.

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That’s what I’d do too.

Consider buying a new washer set as well. You can get a complete set of hardware including cam cover nuts and washers.

There’s no absolute guarantee you won’t upset the head gasket but I think the risk should be small.

You could also repaint the head. Paint it first before removing the nuts.

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Thank you for the good advice. What is the original colour for the Head of a 1963 2.4 ?

Should be duck egg green . Some call it duck egg blue , but you get the idea .
New chrome is nothing like the original , deterioration will start to occur after a couple of years , though maybe not where you are . :sunny:

I had this issue as well, the new studs caps are not very good, or quite right in appearance either

I subsequently found out Hamilton Chrome charge $5 to re-chrome a stud, which is cheaper than a new one. Not practical if you do not have spare caps, but if you do, like me, I will have them re-chromed 14x $5, fit them one at a time

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I agree: only 1 nut at a time. Be sure you do them in the torquing sequence per the work shop manual. first one first, then the second, and so on. Only question I have is should you lightly oil the treads on the studs or re-torque with the studs dry. I think I’ve read to re-torque with dry studs, perhaps opinions differ…

A 2.4 should have no color, just plain aluminium.
3.4 were duck egg green.

I don’t think so .

2.4’s are silver or aluminium. Mine is for sure.

My 3.4 is duck egg green - original paint. The 3.8’s were a darker blue.