I don't recall any accumulators at all. It's a straightforward Piper.
The fuel system, at least on the Chieftain, uses two fuel valves at the base of the center pedestal, where you select the main or aux tanks. There are two tanks per wing. Use the mains for takeoff, switch to aux for cruise, back to mains for landing. As with other Pipers, there is an electric boost pump for each side, and a mechanical pump on the engines.
Did you have a specific concern?
Oh, one more thing. Speaking of fuel...
Line guys routinely mistake this piston plane for a turbine, since Piper made a turbine based on this design, called a Cheyenne. One of the Chieftains I used to fly was down for several weeks with an engine replacement when one of the other pilots took off with a load of Jet A, having not supervised the fueling during a trip. As the engines began to run rough after takeoff, he made it back to the field, but the engines were toast. So was he, gone that week.
Watch the fuel truck!!!!!