773G fuel problem

[Les773G]

I'm having issues with my 773G with about 1790 hours. Used machine in April, parked in garage, went to use it and it started and died. Wouldn't re start, so I started diagnosing. Fuel pickup in tank broke so I replaced it. Charged the battery, started up, used for 3 hours, shut machine off with key and wouldn't start...started diagnosis again...Replaced fuel pickup tube, fuel lines and clamps, primer bulb, transfer pump, still no start. Put a clear hose from transfer pump to fuel pump, primed fuel system, and started engine...runs and stops after a few minutes. Fuel eventually runs back down hose and it quits running. Removed injectors and had tested at dealer shop. #1 was not spraying right, and all injectors didn't pass pressure check. #1 was missing heat shield and copper seal...had injectors rebuilt and tested and reinstalled. Did compression test before and have 540-550 psi in all cylinders. I installed an electric lift pump in the system as well. Started machine and it ran for 15 minutes and stalled when I tried to move it. Machine still doing the same thing! Won't keep prime and stalls after a few minutes....fuel runs back down towards transfer pump....I'm stuck and need help!

 

[foton]

may be if you left the mechanical fuel pump in the fuel circuit (if it has one) and its diaphragm has a hole in it, it is getting a vacuum leak there , make sure you put the new primer bulb in correctly it has a arrow to show flow direction.

 

[flyerdan]

may be if you left the mechanical fuel pump in the fuel circuit (if it has one) and its diaphragm has a hole in it, it is getting a vacuum leak there , make sure you put the new primer bulb in correctly it has a arrow to show flow direction.

If the mechanical fuel pump has a rip in the diaphragm, it can also let diesel into the crankcase, so pull the dipstick and see if it's over full and smells of fuel.

 

[Les773G]

may be if you left the mechanical fuel pump in the fuel circuit (if it has one) and its diaphragm has a hole in it, it is getting a vacuum leak there , make sure you put the new primer bulb in correctly it has a arrow to show flow direction.

I totally removed the transfer pump and blocked off the hole and it still happens...by passed it first, leaving the pump on the engine. Still no luck...primer bulb installed correctly.

 

[Les773G]

I totally removed the transfer pump and blocked off the hole and it still happens...by passed it first, leaving the pump on the engine. Still no luck...primer bulb installed correctly.

I was advised to use an electric pump, inlet in a clean can of fuel, outlet hooked directly to the injection pump fitting, bleed the system and try to start it. Started engine, runs about a minute, and the fuel bubbles up in the hose and the engine dies....am I looking at an injection pump problem now? Nothing I do solves this fuel delivery problem....help!!