hey hef this is what i know so far. fuel pressure at idle taped into feed line into injection pump 25 psi at idle only 15 wide open. Tank was cleaned all new fuel lines filters injection pump with new lift pump installed.
Sucking air, kinked or restricted supply line. Debris jammed up in a fitting. These are e few things to look for.
Good day It could be the component illustrated, hope it helps Kind regards Uffex
It's a totally mechanical fuel system. there's no restriction on suction side of lift / transfer pump. Fuel flow is a steady stream 3/8 in diameter. I will double check for a air leaks. Customer put his own fuel injection pump on so I'm going to call dealer for timing procedure. It seems odd to me that fuel pressure will drop like that but I know a 3406 will drop fuel pressure at wide open throttle. Customer complaint is low engine power
Check to see if it has an "overflow valve" in the outlet side of the inj. pump.. THATS a very common reading if the valve has a weak spring.. it holds at low idle & drops at HI..
Have you got pictures of the fuel pump?
I did not snap pic of pump it looks similar to one off of a Volvo a25c with drive coupling.
The pressure change is totally rpm related. Every click on throttle dial drops fuel pressure evenly .
Have u tried running it out of a separate container.. STRAIGHT into the supply pump.?? I still say check that overflow valve,,
I didn't spend much time Will be back later in week