1.3 fuelling questions

Hi all iv got some issues/potential issues with fuelling on my 1.3 55 plate piaggio porter camper convention.

First of all I bought the camper not running the fuel pump had packed in and the previous owner was planning on fitting an in-line pump off a land rover freelander (this came with it) so last week I set to work and fitted the new pump leaving the old one in the tank , new inline fuel filter before the pump and replaced all the fuel lines with rubber as they looked abit rotten , camper fires up and runs nicely idles and revs up nicely for a couple of minutes then it starts leaking fuel from the purge can under the drivers seat after much fibbing I just added a straight connection on the fuel return so it when straight into the tank
*so I’m now not using purge valve is this okay ? I should also add that the tank breather is not connected to the filler neck as the neck has been modified for the conversion it’s just running along side into open air.

Anyway at the weekend camper is running and passes an mot , so I head to the coast 250mile round trip. Drives fine hills are a struggle but sits at 45-50 mph fine, when you stop at a junction or traffic you can hear the fuel pump whining even though it’s brand new ? this is after say 10mins of driving not on start up. It also seams to every now and then when pulling off junctions jump and lurch for maybe 5 seconds then carry on as normal . Anyway it made the trip but would like to sort these issues before theyleave me stranded.

Thanks
Joel