Nissan/Merc have major issues with the Quest fuel system. There is a recall for some mid to late 90's model vent hose, but not the pump assembly.
The problem is not the Fuel Pump. There is a some kind of fuel stabilizer valve (with a FORD stamp on it!) attatched to the fuel pump in tank. You can just remove and replace it with fuel line. I went ahead and installed a Walbro 255 (with the 240SX install kit) on my wife's 96 Quest. This valve in my opion is the root of all hard start issues with the van.
Also, the butt dyno says it hauls serious *** (7 of them) with the 255 fuel pump
I will put it on our dynojet too one of the days....just have to figure out where to put those twin turbos :ylsuper