discovery

i'm new to this forum,ive got a 94 discovery 300tdi i,m about to order a cambelt and i think 2 pulleys ? never done a belt on a landrover before so may need a little advise off you knowlegable owners.iv'e been running it for the last 18 months on my home made fuel but have had problems with the naff lift pumps .does anybody know if you there is a heater system for the fuel?and have any of you fitted a kenlowe electric fan ?does that save fuel