John Deere 4020 diesel wanders, unable to override throttle

pmarkel · Oct 7, 2017

Yesterday while chisel plowing, my father noticed that the rpms we're wandering greatly on my 4020. As soon as load would drop off on the tractor, it would speed up dangerously high and the throttle control would not override to stop the engine when moved counter clockwise. In other words, he could not control the speed of the engine. As I am new to diesels, should I be thinking throttle linkage issue, governor issue, or something wrong with the injection system? Thanks,

Pete

fdt860 · Oct 7, 2017

Weight retainer ring broken.
Remove injection pump and rebuilt it.

David from Kansas · Oct 7, 2017

Several years ago my 4020 engine started running erratically so had son rebuild injection pump and all was fine.

Dieseltech · Oct 7, 2017

Injection pump needs serviced NOW! BEFORE the broken parts inside seize the hydraulic head and break the drive shaft..

larryanderson · Oct 7, 2017

The injection pump needs rebuilt.The last one I had done was $600 exchange for a completely rebuilt pump or you can have yours done and it will cost about the same.If it is a 69/70 they have the short pump which parts can be limited.

pmarkel · Oct 8, 2017

(quoted from post at 06:28:12 10/07/17) The injection pump needs rebuilt.The last one I had done was $600 exchange for a completely rebuilt pump or you can have yours done and it will cost about the same.If it is a 69/70 they have the short pump which parts can be limited.

thanks all for the advice, I will pull the pump. Any particular tricks to doing so? From the service manual, it seems installing the injection pump is much more difficult than removing it.

John Deere 4020 diesel wanders, unable to override throttle

pmarkel

Member

fdt860

Well-known Member

David from Kansas

Well-known Member

Dieseltech

Well-known Member

larryanderson

Well-known Member

pmarkel

Member

Similar threads