Hi can anyone tell me if a silver bosch fuel pump from a injected sierra will suck fuel . As pump is looking like it will be mounted half way up the tank side externaly

Sucking fuel is a bad idea in warm weather you could get vapour locks and also could shorten the life of the pump.

However a couple of inches above the bottom of the tank is ok.

Sierra's have the pump below the tank for a reason.

Once fuel is flowing its not an issue, however the pump cannot prime itself by drawing fuel so unless you start with more than 1/2 tank full you may have problems. An EFI pump drawing air will ruin itself in a short time.

There is a way out, use a low pressure diapham pump (which can draw air) to circulate fuel to a swirl pot up front, then mount this above your EFI pump and have a superior setup.

Regards Mark

Cheers Mark
I was hopeing to get away from having to have 2 pumps
the feed pipe is 15 mm so there is a fair amount of fuel head i will just have to get the pump as low as i can