john deere 870 with yanmar injection pump throttle inoperable

bbpb9146 · Oct 11, 2015

i have an jd 870 that has been sitting for about 4 years and had the injection pump pistons freed and now can't control the throttle what could be the problem as soon as it turns in it idles up to about 2500-3000 rpm but won't idle down or up with the throttle and fuel shut off on pump doesn't work either upon tear down the slots on the pistons are all off and don't know if they need to ben in a specific order for everything to work properly. When i first got it, i was able to get it on and it would run away, i got the governor freed and now it turns on and just goes to 2500-3000 rpm and can get it to come down but it doesn't run away anymore. any suggestion would be helpful. and now really wanting to take it to a shop because the wanna charge me 100+/hr min. 3 hrs just to look at it thanks

super55 · Oct 12, 2015

When you say "you can get it to come down" do you mean you can drop the RPMs by manually manipulating the linkage??

I'm not familiar how the pump/governor works on with diesels but with a couple of my old gas tractors that were having similar issue. It was an issue with worn parts usually being the return spring. I've fixed a couple by just using the lightest spring possible to get the linkage to return to idle position and still allow the governor to allow more fuel when needed.