I have a cat 312b that runs strong, no sputtering or missing. Solid rpm. I track or move the controls and it starts to lose power. While under load, Using several stick functions can cause it to die. If I let off the controls it will recover immediately. I have found 1 banjo bolt and cleaned it, No help. Is there more than 1? Also emptied fuel tank, replaced fuel and hydraulic filters. Checked fuel lines all the way to the tank. Could it be the fuel injector pump? I don’t notice any black smoke when bogging down which seems to me it’s fuel related? I’ve been fighting this for a month. Thanks for any help!
Hi, Welcome to the HEF. If we think about things that should check from electric side regarding this issue there are few. 1.Engine speed sensor. 2.Pump Higher delivery pressure sensor. 3.PRV solenoide. These components together with controller will prevent the machine from stalling. So if you know how to enter the machine's data mode using monitor panel you can check whether rpm signal & Pressure sensor signal receive to the controller. If you do not know how to enter the data mode, disconnect the connectors at the component ends and measure the resistance of rpm sensor and PRV Solenoid and put the readings here and will see whether those with in the correct values. And mention your machine's serial number as well.