I just bought a JD 310D and can’t get the idle lower than 1500 RPM. I completely removed the adjustment screw and then took the cap off. I’m not familiar with the inside of this injection pump but it seems like there’s a spring missing or something as it does not move things back the whole way when letting off the throttle. This is a JD reman pump but I have no idea how many hours are on it. The machine has 3900 on it. Do you think a diesel shop can just fix whatever is going on or do you think it needs a new pump?
Try backing the adjustment screw out on top of the cap. It takes two 5/16'' wrenches. I'm not an injection pump expert but that does adjust the low idle speed. It looks like it's ran in farther than it should be. It may have been adjusted for a constant speed application.
That worked! Thank you very much!
The one u took out was the preload stop screw.. Put by it back in, run it down till it in increases the speed and back out 2 full turns.. That way, when u go from full speed to low idle, it won’t shut off on u..
Good, I Hope the machine does a good job for you!