Having trouble with fuel system. Backhoe would start at 1st runn for about 3 seconds then die. Ether it and starts up and runs fine. Set still for 15 minutes and does the same thing. Bought new fuel pump because primer lever would flop all over on old one. Put new one on and primed fuel all the way to the injector pump. Went to start it a day later and the primer lever feels like there is nothing there. Took back off and primer lever has lots of vaccum. Any help would be great!
The primer lever pulls the diaphram in the transfer pump. If the cam is pulling the diaphram, the lever will flop. The cure is to bump crank the engine to get the pump oiff the lobe then reprime. The problem you are having is usually a air leak on the suction side of the fuel lines, this allows fuel to drain back in to the tank. If you have any dampness in the lines or filters that is a sign of a leak. Since air is thinner than fuel, a miniscule leak will cause a problem. I've had problems with steel filters that have a plastic screw on water bowl. These sometimes will allow air to enter but not cause a visible fuel leak.
Also check for a antidrin back valve on the return line at the tank. If it is stuck open it could be siphoning the fuel through the return. Also does it do this with a full tank of fuel?
Hello, I´m having the same problem as fasstang65 in my case 580k. Problem dissapears if fuel tank is half capacity. I´ve put a new inline until pump but problem persists. where could be the clue?? thanks
Like Goose said there is a anti-drain back fitting at the tank on the return line. This is just a check valve that holds back fuel when the level is low, but should not be a issue if the tank is 3/4 to full. Also said the cam has to be released against the pump so it can stroke the diaphram with the lever and prime the system by hand, 12 volt at the pump shut off with the key switch on, bad coil or plunger in the shutoff, low engine rpm adjustment, fix areas that look wet and may be causing air leaks. Some machines also have the inline filter at the frame also that may need to be changed out.
Thank you for your answer Goose, I've already chequed 12v in the shutoff solenoid. I'll try with the check valve. Didn't knew it was present and in all the machines. It's an annoying problem, my batery and starter motor are suffering and will die. Thanks again
I just went through this this past fall.
Just wanted to thank for your help. Finally changed fuel pump and now all correct.