I have a 1982 John Deere 350-c it has a 3 cylinder John Deere diesel in it. it will start and idle fine, however when you idle it up it starts surging. The rpms will drop almost like it stalled, but before it shuts off it will throttle back up. it will do this several times a min and it is getting worse. Any help is greatly appreciated. I know this forum is mostly about trucks, but I thought people on here will know just how to fix my issue.

 

what is your fuel pressure
last time you changed the fuel filters
is there any leaks
sounds like it is getting air into the system, not sure, need more info.

 

we wound up replacing the fuel filter, fuel lines, and fuel. we also checked all the seals around the injection pump, and injectors. through all that we were able to eliminate most of the surging, however it is not entirely gone so we believe we will replace the injectors, and check the timing on the injection pump.
Weigels gave us a bad batch of fuel. a lot of the people around us were also having similar problems after using Weigles fuel.