i would put a pump on demand electric pump in line with the mechanical pump .FRB

FRB
FRB Model Unique Features:
For applications where battery life, low noise and best
durability are important and fuel quality is questionable

· Flow: to 225 lph (60 gph)
· Ampere hours: up to 70% less than FRA & FRC
· Continuous duty life (diesel fuel): &gt18000 hrs
· &nbspWeight: 0.83 kg (1.83 lbs)
· &nbspPump cycles only when fuel is demanded
· &nbspReplaceable filt