RE: Proper Fuel Line Size
The brass tube on a DuBro tank measures 3.22mm or just over 1/8 in. The line should be a bit snug but not overly tight. Only time I bother to barb the brass lines is on my YS engines. I do cut about 1/8 inch of fuel line and put it over the main lines then slide it back over the nipples and tank tubes. This just tightens the lines so they don't slide off.