sunbeamtiger.co.uk

I have a stop cock and hose connector brazed onto the top of the offside fuel tank. It doesn't look like it is supposed to be there and serves no possible use. I've had the tap turned off and a cork wedged over the end for the past few years.

Anyone know what it's for?

It may have been used at sometime in the past to pressurise the tank in order to check for leaks by immersing it in water and looking for bubbles.

is the balance pipe still connected that links the 2 tanks to let the air out

Yes, the balance pipe is fitted, I changed that about 2 years ago.

I may look to replace the pipe from the filler cap that the balance pipe is connected onto and possibly replace the rest of the old rubber connections with some silicone petrol pipe. Winter job methinks.

I think I may have found out what that tap was for on my O/S fuel tank.

I recently met up with the guy who I thought was the second owner of my Tiger. He told me that the chap that he bought the car from wasn't the original owner and that the car was initially owned by a guy who used it a lot for long journeys in France. It had a temporary additional fuel tank fitted just behind the front seats, on the rear parcel shelf. The tap may have been how the existing tanks were linked to the auxiliary tank. Not something you'd get away with these days.

At that time the car was on a private plate which was sold off in the late 90's. The original plate wasn't re-used.

I've contacted the DVLA to see if I can trace the original owner and get some pictures of that fuel tank.

Would be very hand for a return to tank line to recirculate the fuel if your having any hot running problems with modern Ethanol based fuel, basically reducing the time the fuel is sat in the hot engine bay.
About to do something similar on the GT but using the fuel filler neck for the return point.