Hi
I am currently rebuilding the engine of my XK 120 ots and have found considerable corrosion in the waterways. I am in Central Florida and am seeking a welder/ engineer who is capable of repairing waterways and replacing valves and guides. I am willing to drive for competence. Thanks in advance for any help.
Cheers
Tony
If you are looking for a good shop to do the work I’d suggest Coventry West in Lithonia, just east of Atlanta Georgia.
The subject has come up a number of times on these forums.
Search the archives for cylinder head corrosion welding.
I can see no reason to assume that corrosion has confined itself to places you can see.
Some SS models had alloy heads and we sectioned one to see what it was like inside the water jacket.
As you can in the pics it was bad, And curiously very bad in localised placed and not in others. A particular problem was shown where corrosion had eaten through one of the pillars that surround the head stud… So all that was retaining coolant was the washer on the top
. But also the weakened pillar meant that when tensioning the head, the pillar would start to collapse rather than transmit the tension down to the head gasket.
The other issue with welding is what type of rod is used
The cylinder heads were of an alloy with particular properties among which were resistance to corrosion and heat treatability.
Rods can be bought in particular alloys but when I asked a local specialised welder about that , he pointed out that minimum quantities applied , from memory 100 sticks and he wasn’t prepared to buy it in that quantities for jobs that were not common.
Then the weld itself will be soft [ like cheese] until the alloy is heat treated
The head can be re heat treated but that involves removing all ferrous parts first … studs, guides, valve seats.
A local specialist maker and repairer of cranks and alloy blocks and head told me that about 1/3 of jaguar heads that come in are soft [ and fail the hardness test]
The hardness test is very quick , at its simplest , I saw a drop ball tester the other day . A ball in glass tube, allowed to drop into the surface being tested . If it bounces up the the specified marking it’s OK .
I know this all sounds tedious but would we be happy if Jaguar made cars without quality control to this extent.
Hi,
You could try BMC classics in New Smyrna Beach. Very capable engineer/mechanic. Speak to Harold… Cheers. Bernard