2555 not increasing rpm

[4020millj]

I got the 2555 put mostly together and it starts and runs great at a low rpm. With or without the linkage to the injection pump it will not increase rpm. I have checked fuel supply coming in and return line is not linked or pinched. I also don't have a tachometer working to know what rpm it is exactly. On the tachometer how to you figure out if the sensor magnet is bad? The tractor runs very smooth it just won't increase rpm with the pump linkage set at full throttle or at low idle. It has a cab and turbo. Thanks.

 

[JD Dave]

Sounds like an injection pump problem. Maybe something like a lever inside the pump is broken or out of adjustment.

 

[4020millj]

Sounds like an injection pump problem. Maybe something like a lever inside the pump is broken or out of adjustment.

I figured out more, after looking more at the parts book I am missing #3 lever. I bought the tractor in apart condition and am putting it together. Ordered it from Jd. Does anyone know the size of spring #12. Jd dealer is going to try to see if main Jd will give them any specs. I have a spring that looks correct just want to be sure.
I can increase rpm now by rotating the spot where #3 goes.
If anyone could put a picture of their pump/linkage I would appreciate it. The Jd books are too blurry.
Thank you much.