Silicone lines good for diesel and Bio-diesel?
 

I have to lengthen my fuel lines a little on my truck, and instead of purchasing completely new lines (pump and return), I was thinking about sectioning them out and adding some flex line. I only need 6" more of line.

My question is, with plans already in the works to go to WVO, I know that my engine (97) has the viton seals, and that rubber is not good to use for fuel lines with this. So would silicone be a safer and better alternative? If not, what else, and where to get them?

It is my understanding silicone should not be used in fuel/oil lines, (let alone biodiesel) as it will degrade from the inside out showing no signs of weakening until it fails completely. Viton, as expensive as it is, is the only way to go for biodiesel fuel line. McMaster Carr (link: McMaster-Carr#) is one place I know of which carries Viton lines. Not too bad price-wise by the foot, i.e. 3/8"ID is about $5/ft, but they only sell minimums. (IIRC, 25 foot coils). Surely there's someone else out there that sells smaller quantites. I just haven't had the need to research it for myself. Hope this helps.