Hello experts, we have a JD670CH which has about 3000 hours on rebuilt engine, fuel injector system etc. It has developed a problem where it briefly drops power under load; engine will "flutter" and revs run up and down of their own accord while idling. Have checked electric connections on injector pump and am chasing anywhere that air can enter the intake side of the fuel system. Has anyone got any other ideas we should look at? thanks in advance.
What kind of fuel injection pump? If there's more than one wire, I don't touch it, but somebody else might be able to help you with that. The only thing I'd check is the fuel supply pressure, assuming this uses a transfer pump and a traditional pump-line-injector system, with an inline or rotary fuel injection pump. Tee into the fuel line between the filter and the injection pump, run a line to a gauge in the cab, and you can see what the pressure is when it's running smooth vs when it's hunting.
Hello Demler, we went over the fuel system and finally discovered that when we moved the wiring loom that controls the electric throttle, the revs jumped about. Untangled it, cleaned and taped it up and the problem has gone. thank you for your help.