I've got a leak at the fuel filter adapter. There's a sensor(?) at the top, beside where you open the bleed. It's got 2 wires going into it, and when the engine is running, it leaks and begins to smoke! I though this might be a fuel heater, but am not sure. The local parts idiots haven't got a clue and can't order it if I don't know what it is.

Thanks

I think your right, that is the fuel heater, water sensor is near the bottom.

Fairly common problem, I see it mostly on the 7.3s but I've heard it happens with the 6.2s.