_lewisgboone@gmail.com_ (mailto:lewisgboone@gmail.com) writes: I would like to drill a hole in the top of my diesel fuel tank to add > a fuel pickup for an espar heater. I am concerned about the risk of an > explosion when drilling the steel. Comment; When I installed my Webasto diesel heater, I had the mechanic do one thing for me: tap into the genny supply and return lines to "feed" the Webasto when he did some genny work for me. These lines ran within about three feet of the Webasto, so routing was easy. They work fine, individually and together. The diesel heaters pull only a relatively small quantity of fuel. If you do decide to drill into the tank, use some of 3 in 1 oil,or lube oil, to cool the drill bit and don't press to hard; the drill will become hot to the touch but won't be a danger. The more often you stop and the less hard you press, the cooler the drill will stay. And likely the tank metal will dissipate most of the heat anyway. You can always run a return line (if the ESPAR requires one) into another existing line. Rob Brueckner 1972 Hatteras Yachtfisherman