Thanks Baz, yeah I can hear the pump running, is it ok to run the pump while driving? I'll check it out. I've sent DB an email, just waiting to hear back from them
Yes I pretty much only run the pump / transfer while driving, its probably a 10 amp draw - or there abouts, so can suck a bit out of your BAT if stationary. Most pumps will burn out if left running accidently with no fuel to move... so I also monitor the transfer.
check with BD on the flow rate of the pump too, this way you can set a timer if you want to move only as much fuel as you want.
Its easy to forget its pumping when driving etc.... done that before.... hahaha ...
If the pump is running, then it sounds more like a vent issue... slowing down the transfer rate as it fights to push the fuel over to the main tank.
did you put a breather line between the two tanks, to equalise pressure as much as anything ?
as fuel goes into the main, it pushes air back out to the aux, and the aux vents back up to the filler cap...type thing, will also help when filling tanks...allows the air out.... across both tanks