Why will bobcat run when I prime for about 15 seconds and die but if I hang fuel supply to injectors it will keep running

WELL MOST BOBCATS NOW HAVE ELECTRIC FUEL PUMPS NOW , SO REPRIMEING FILTER IS EASY YOU JUST KEEP CYCLING KEY (NOT TO START) WHEN FILTER IS PRIMED (NOTED IN PITCH CHANGE OF FUEL PUMP SOUND) THEN YOU CAN LOOSEN ONE INJECTOR SUPPLY PIPE (NOT REMOVE) TILL A HINT OF FUEL DRIPS OUT OF IT , CRANK ENGINE TILL IT TRYS TO START , THEN STOP AND TIGHTEN THE INJECTOR PIPE , THEN START NORMALLY ALLOW TO RUN FOR A FEW MINUTES BEFORE RESTORING TO SEVERVACE EVERYTHING
CAUTION : AS WITH ANY DIESEL THEY USE VERY HIGH PRESSURE PUMPS TO INJECT FUEL INTO ENGINE ALLWAYS KEEP EXPOSED SKIN AWAY AND SHIELD FACE/EYES WHEN WORKING ON THIS FUEL CAN AN WILL ENTER YOUR SKIN AND CAUSE YOU FATAL PROBLEMS !!!! SEEK MEDICAL HELP RIGHT AWAY IF FUEL ENTERS YOUR BODY !!!

either on the pump or fuel filter case there will be a small hand pump that you pump the fuel to the fuel pump. there are small bleed screws at the filter or on the pump that you open partially and as you pump you will see air and fuel come out. keep pumping until you get solid fuel then close off. The pump may be round so you will have to unscrew the top and that will allow the pump plunger to move . When finished do up the plunger again. Once the air is out of the system, crack the injector line nuts at each injector and crank the engine until there are drops of fuel at the nut, tighten up the nuts and it should start.

if the bobcat starts and then runs for a short time then dies the first place to look is the fuel system.fuel filters are the most common problems that i see replace those first.i have also found some junk inside the pickup tube inside the tank.there is probably a ball type hand pump to prime the fuel system.give that a squeeze and see if its hard.if thats the case there shoud be a small screw on top of the fuel filter.loosen that screw and see if fuel comes out when you sqeeze the ball.if your changing fuel filters this is also where you blead air from the system,keep pumping untill there is only fuel and no air.if you still get air after pumping for a long time then your sucking air into the system between the tank and pump.after you get fuel there close the screw,loosen the injector lines going to the injectors,crank the engine,and tighten when fuel comes out (keep clear because that is high pressure fuel).after you get fuel at all injectors and they are all tightened it should start.

filling the filters before installing will make priming go more quickly.
once the pump is primed crack open the fuse line at the injector while cranking until you have fuel pulsing out, close it then move on to the next injector.
keep doing this until the engine runs smoothly.
it may start running before all the injectors have been purged so keep clear of all moving parts and a fire extinguisher handy would be a good idea.

first check the fuse and relay for fuel pump. heres how to check the pump. get under car and put hand on bottom of fuel tank, then have a person turn key to on . if pump is ok. you will feel a vibration in tank. you may have to do this a few times because a fuel pump only runs a few seconds to get fuel pressure to engine then shuts off. but when vehicle is running its on all the time to supply fuel to engine.

why did you replace the filter and pump?
did something get in the fuel?

check the injectors and spark plugs

in my car someone put flour in the fuel tank and the fuel pump, pumped it into the injectors where it cloged them up

so i had to replace injectors pump filter now it is good

The anti thieft system is keeping it from running.

check fuel pump possible going bad, fuel pump doesnt give a trouble code

Was gasoline left in the tank during off season? Sometimes gas will break down and clog the jets in the carb. The priming bypasses the carb so when you put fuel in by pumping the bulb it runs, but dies becasue no additional fuel is coming through the carb after the primed fuel is burned off. Sounds like you need to clean the jets in the carb and in the future, use Stabil in gasoline to keep it from breaking down.

Did you change the fuel presure regulator located in the throttle body?