420 john deere tractor

[wayne norman]

i have a 420 that surges, new point plugs and rotor, rebuilt carb, new manifold gaskets. it surges at all rpms and under load or not. any sugestions?

 

[Anonymous-0]

Did you inspect the governor? It may have a broken spring.

 

[Jake Winn]

Check the throttle shaft as a possibility. I have seen the shaft come loose from the arm where the governor arm attaches. The arm stays on the shaft, but the butterfly will move on its own.

 

[Nick Renchen]

The only spring it has is one that is on the outside. might be wore out linkages