Does Bosch pump need a lift pump?

[meerkatmag]

Just a final update unless anyone else is having similar issues. I have been driving van with new lift pump fitted and the whistle has gradually got quieter and now is gone completely. So I don't know exactly how but it seems to have fixed it after all. Needed about 50miles of driving. Perhaps some air in the system has been gradually pushed out?

To answer the point that others have managed without a pump, my van is a massive a-class motorhome (imagine winnebago) and with 100l of water and 4 people and a very unaerodynamic shape I think the fuel demand might be higher on average than a usual van?

I did check the rest of the engine bay, exhaust etc all totally tight no sign of any loose bolts, I did find a tiny crack in my heater pipe but have sealed it and didn't fix the issue so assuming that wasn't it.

Thanks again for all the help, it's so important having this forum as most garages here won't go near an old transit.

Cheers

[Chug]

Glad it seems to have sorted itself out.
My tipper is regularly loaded to max weight and has no lift pump and it keeps up with the fuel demand so a lack of a lift pump shouldn't affect the running.

[meerkatmag]

I think there's clearly something else going on, as you say (and others have too) it should work without a pump. Maybe my fuel lines are blocked and reducing flow? One other thing I noticed was my cold start fuel reservoir has a vent on the top, and the whole unit was slightly slanted and had dropped the level of the vent close to the level of the fuel lines. So possibly a source of air getting into the lines?

Anyway, certainly a mystery but if it's working I'm going to leave it be for now.