Hi all,
I got a Relieve Valve Body C.1088/C from @Roger_McWilliams and I have now made measurements and a 3D CAD model of it, plus I have made a modified version of it (slightly longer body to accept a modern seal as the original fibre seal is completely NLA, C.1710 Washer (Fibre) between Relief Valve and Housing. The original washer is 1.5mm thick and a modern substitute I was able to get is 2.5mm thick. I am not sure how well it will seal, but it feels really tight and has a rubber double “lip” inside metal casing and is intended for hydraylic systems so I think it should be good.
I can e-mail if someone wants the file (please state in which format, SAT, STEP etc.) and in case I manage to get a workshop to use their CNC machine to mill some for me out of brass I can let you know in case someone would like a spare. AFAIK it’s about the same cost regardless if they make one, ten or twenty for me. 
And I am thinking of having them make also new oil pump shafts as mine did survive ok, but I think the end that drives the oil pump has taken quite a hit (as it jumped) so I thought that as long as I have it at hand, why not also make a model and see if someone would make new ones at reasonable cost, as it is a very simple shaft after all.
BTW mine is from the 1947 MKIV engine #SL2199 so I read from an older Jag-Lovers Pre-XK thread (with Ed) that apparently the later MKV version did not have the oil groove in the bottom part anymore. Maybe that one got mine going with cold oil?
And what is that groove in the middle for? (the horizontal one, I know the vertical ones are the keyways for the two keys. Again for oil or something? (I think it sits just above the bush that has one 'thou clearance, just like the rocker shaft and rocker bushes.)
Cheers!
PS. I have never ever used inches and fractions in drawing before, PLUS I have worked as an architect, NOT engineer, so my dimensioning is probably very funny for mechanical engineers, BUT the 3D model and the dimensions should be pretty accurate.
relief-valve-body.pdf (52.3 KB)
relief valve body-2021.pdf (50.3 KB)
