This is what tank looks inside. There is a little "bucket/baffle" inside at the bottom. Return line has to feed into this. Otherwise, when going around a corner and fuel level is low, the "bucket" will be sucked dry if return line would exit elsewhere.
So i made this, and fitted it inside.
Basically the return line goes to the very top of tank, where it exit in a rectangular piece of square tubing. (Square tubing is welded shut on it's sides). From this "box", another pipe reaches downwards to exit into the "bucket/baffle". At the top, there is a small 1.5mm hole in the square-tubing box. This is also aimed at the bucket. If fuel supply stops, air will enter through this hole at top of "inverted U" inside tank. This will prevent fuel to be drawn out of return line.
An 8mm hole was drilled in tank near existing fuel inlet/outlet. Return line exits there. It was brazed there, and a washer was fitted around when brazing, for extra strength and good seal.
At the top, a nut was previously welded to upper square tubing part. A hole was drilled on top of tank. A 6mm bolt fixes upper part to top of tank, as a steady, for better vibration resistance.
Copper washer is used to seal.
Pipe used was 8mm metal, sourced from a donor 412 car.
Photo inside tank looks much worse than it is. A fluorescent "energy saver" lamp was passed through the filler, and photo taken through sender hole on top.
