ohiobrushcontrol
New Member
Hello guys! This is my first time posting so bear with me. ENGINE SERIAL #44407550 - I have a 2010 caterpillar 4.4L that is kicking my butt. Engine is in a brush bandit 250xp woodchipper. The engine currently is a crank no start. I have no codes. Engine WILL run on starter fluid, so I know my base engine is good. I have some sort of fuel problem. I have the common rail system, with a 320d injection pump. I have replaced both fuel filters. My low side fuel pressure, while cranking is 10 PSI (it should be 50-70psi). My low side pressure is leaking passed my fuel metering valve (solenoid on top of injection pump). I know this, because I pulled the fuel return line off the injection pump and while cranking, watched fuel come out of the port. If I block off the fuel return line port, on my injection pump (Dead head my low side pump). MY low side fuel pressure jumps up to 60psi. I have replaced my fuel metering valve (solenoid only), but the concern is still present. I LOAD tested the metering valve circuits (both test good). I found I am getting a pulsed ground signal from the ecm while cranking (I believe is normal) but on the power side I am only getting 1-1.2V with key on or cranking. I though i might have another sensor pulling the voltage down so i unplugged EOP, MAP, ECT, FRP and both timing sensor, one at a time but is still only have 1-1.2V. I pulled the metering valve off and plugged it into the harness and I am not getting any movement. Based on this I replaced the ECM and had cat flash it. My concern is still present. I have checked my pressure relief valve (attached to my fuel rail) no fuel coming out. I don't understand why my pressure jumps up to where it should be when I block the return port. I feel like I should have movement and more than 1.2v going to the metering valve. maybe a weak low side pump? I am at my wits/wallets end with this thing. Any help would be appreciated.
I have attached pictures of the metering valve and injection pump
Thank you.
I have attached pictures of the metering valve and injection pump
Thank you.