I have a 328 jd skid steer. I can not get the fuel pressure to stay up to start, i have changed the fuel filter an housing with the new hand pump. I took the duel lines off the tank and put the draw line in fuel then watch the return line flow freely in a can every time i pumped the primer. I can hold the return with my finger and it pumps up hard like it used to. I checked all the fuel line no leaks. is there some kind of check valve in the system? Any help would be a blessing.
Let's start easy... Does it have 2 filters in the fuel system? If so, does the filter closest to the tank have a water bowl spun on the bottom of the filter? If so, is the O-ring present between the black top of the bowl and the bottom of the filter? Next, when you pump the primer, and you say it pressurizes, are you checking for pressure at the primer outlet, after the mechanical lift pump, or after the filter closest to the injpressurize, Return line, you say. Where is that? Does the hand primer get difficult to push after priming a while? Could you have the system primed but have an issue with the stop solenoid?
Welcome to HEF Michael ! Serial number? There should be 2 filters. An in-line filter (p/n T257865) at the tank and of course the filter you replaced. Make sure the in-line is replaced as well. Do you hear a loud clack when you key on. That would indicate the fuel shutoff solenoid engaging. You should really install a fuel pressure gauge to be sure it is a fuel pressure issue and it would help with troubleshooting. Yes there is. On the fuel line side of the engine towards the flywheel end there is a fuel return fitting coming out of the block. That barbed nipple in that fitting is a check valve (p/n RE540179). That is a common issue with those engines.
RE540179
I’m not familiar with that set up but I am familiar with fuel systems.. If u can hold your finger on the outlet/return side and it’ll pump up, u have an overflow valve problem.. The overflow valve keeps pressure in the fuel gallery, allowing the pumping plungers to have enough fuel to pump.. & any excess will go back to the tank once it’s reached a certain pressure.. If the overflow valve is bad/broken, the fuel coming into the pump will go straight back to the tank..not filling the gallery..