bsamot69
Well-Known Member
Our CAT 480f backhoe will not start. It cranks. The machine has been operating pretty flawlessly since I replace the transfer pump some months ago. One morning I tried to start it and the battery was dead. I removed battery and recharged it. Now, it will crank but not start. When the key is turned on the fuel pump runs and keeps running. The machine does not start. I believe the fuel pump initiates for a few seconds then turns off prior to charging battery. I have an inline clear fuel filter installed and it showed barely a trickle of flow. The tank is near full. I noticed the fuel line from tank to pump had a small tear so was pulling air. I repaired that and pulled the filters, which had fuel in them, then reinstalled them. Turned key on and filters filled up but the ful pump continues to run until key is turned off. The machine still cranks and does not start. I checked all the fuses and none were blown. I should mention that before I replaced the fuel pump months ago I had filled the filter and seperator with fuel so machine would run so I could move it to the repair area. Now, it will not start with fuel filters filled. The return line into tank has good flow. I am not sure the direction to go to diagnose problem. On this machine, does the fuel controller turn on and off the pump? Is there a sensor or other input to check? Is there a wiring diagram available so I can check the controller input/output? The power and grounds? I'm waiting on replacement fuel filters just in case it is a plugged filter. Any advice or suggestions are greatly appreciated. The serial number JWJ01898