Mark IV 3.5L fuel line

I have to create a new line from the tank valve to the fuel pumps. Where can I find the fittings to attach to the fuel pumps, and connectors if the line must be spliced. Various sources sell a copper line for an XK 120. This could be cut and perhaps do the job, but I would rather use original materials.

I would buy new copper pipe as forming it hardens for changing it afterwards, i find wehavea comany specialising in brass, copper sales , or trying places selling copper tube for air con, the fittings are fairly standard, BSPF and from memory solder on olives.
You might try buying one of those springy pipe benders to avoid crushing thhe pipe when bending it.

My 2.5L SS has 5/16" diameter copper tubing, and my 3.5L Mark V has 3/8" diameter, as does my XK120. I suppose the bigger engines needed a larger supply line.
These sizes are readily available in the USA in 10 foot and 50 foot coils, so let us know if you want a few US suppliers contacts.
The Mark V and XK120 use a different fuel pump, SU LCS, located under the car, and I believe the end fittings that attach to it are different than for the smaller pumps used on Mark IV, so I don’t think an XK120 kit would really work for you.
Here is my favorite source for BSPP fittings.

Thank you for the info.


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Yes the MK V used bigger dia pipe. The 3 1/2 SS / MK IV had 5 /16" But for all that the ID of the fittings wasn’t bigger.Perhaps the bigger pipe had more surface area, the better to absorb heat from the engine compartment : >)
The suede green is very attractive on these cars.

Fuel line update,
I got a quick reply from They stated that I need Part ABF297 and AUC 1094. I presume that one is the olive and one is the cap. I have ordered these. If they are the correct size I should be able to find tubing too match.
My tubing is 5/16 on the outside and it is not clear to me whether tubing is measured on the ID or the OD.

Pipe is measured on the ID: tubing is measured on the OD.

But the confusing aspect is that on these cars the fuel line is called a petrol pipe in the literature. Nevertheless it is measured on the OD.