A10 fuel tank question

[chaz]

on the A10 tank I have a problem, fuel was feeding from a 1/4BSP outlet on the left side at the front of the tank, on the right side is another outlet, also seems 1/4BSP but someone has fitted something in and plugged it. I had a length of fuel pipe on it but that has eaten away the pipe and on removing the pipe from the tank was plugged. this is now leaking. Presumably the second outlet provides a feed from both sides.
I need to find a tap that will fit on the 0.320" tube exiting the tank otherwise its a length of pipe and a tee piece to the other fuel pipe but will only be able to shut off one side.
the other question is... at the rear of the tank underside there is a 1/8BSP plugged hole. I can understand two but what would the third be for?

[JulianS]

Thought the usual setup for A10 was a 3/8 BSP bosse either side towards rear of the tank?

[chaz]

this has two 1/4 outlets at the front and a 1/8 at the rear, the 1/8 is plugged off with a taper plug from work and Ive itted a brass 1/4 so know the sizes, the tank is a round badged one ,centre fixing, offset filler cap, the bike is /was a 1950's

[idie]

Your tank sound like the one on my 1949 M33. This has a copper link pipe to join the two halves of the tank. There is only one outlet for fuel to the carb at the rear.

[chaz]

idie
that sounds plausible, the left hand 1/4 now has a fuel tap, the right hand seems to be sealed in as large grips have not been able to move the fitting, and could possibly link both halves to get all the fuel out of the tank (forgot about the link).
. might have to re install the link then.

[chaz]

 now sorted, bull by the horns moment and drilled the right hand tube out, surprise surprise I got it dead centre, ran a 1/4 BSP tap down the hole and now have a new pair of brass taps linked to the pipe and a filter in the line. rear 1/8 BSP hole plugged up