If you suspect there is water and bacteria in the fuel treat it with biocide the day before you want to start it. Otherwise I agree with the fellows above....nothing to fear except bacteria.

Once the bacteria is killed it should run through the filters, but if you suspected fuel issues four years ago probably would be good to start by changing the fuel and air filters.

Good luck!

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.