fuel lift pump, when is it needed

[simonfraser]

been looking on the net, looks like the main fuel injector pump can suck the fuel in from the tank as long as there is no air in the line ?
and the fuel lift pump is mainly needed if there is air in the line or possibly the fuel height in the main tank is very low ?
in my set up the head of the tank is just above the primary filter and high pressure fuel pump.
depth of the tank 60cm max.

how do i know the lift pump is even working ?

its on a KAD 44 EDC

 

[omega2]

maybe when you need to bleed the system??

 

[volvopaul]

been looking on the net, looks like the main fuel injector pump can suck the fuel in from the tank as long as there is no air in the line ?
and the fuel lift pump is mainly needed if there is air in the line or possibly the fuel height in the main tank is very low ?
in my set up the head of the tank is just above the primary filter and high pressure fuel pump.
depth of the tank 60cm max.

how do i know the lift pump is even working ?

its on a KAD 44 EDC

The pump is always needed to stabilise a pressure of fuel inside the injector pump .
Your theory of the tank supply is wrong , liguid cannot make its own way uphil unless it’s syphoned , the pipe at the top of the tank goes Tom the bottom of the tank , unless your tank have a bottom outlet which on a boat is totally wrong.

 

[simonfraser]

tnx Paul, as its all working my lift pump must be ok at the moment.
no bottom outlet.