3 Cylinder Tractor Running Wide Open Only

[AndrewCrisp]

This is a 2001 jd 430 with a yanmar 3tne84-ejts 3 cylinder and we replaced the leaky o rings on the fuel delivery valves on the injection pump, and now after replacing and putting everything back the tractor will start right up and run wide open with no way to kill it other than to clamp the fuel line shut. It is smoking a bit white when running and it cannot be shutoff with the key, we took the inspection plate off and the rack seems to be moving back and forth freely with the solenoid from the key switch, the throttle lever is moving, but has no effect when the engine’s running. I have read that it may be possible for the plungers to get out of wack when removing the tops of delivery valves but I’m unsure how to address this. I have searched many other forums but have yet to find a solution. Any help would be greatly appreciated.

 

[ponytug]

This is a 2001 jd 430 with a yanmar 3tne84-ejts 3 cylinder and we replaced the leaky o rings on the fuel delivery valves on the injection pump, and now after replacing and putting everything back the tractor will start right up and run wide open with no way to kill it other than to clamp the fuel line shut. It is smoking a bit white when running and it cannot be shutoff with the key, we took the inspection plate off and the rack seems to be moving back and forth freely with the solenoid from the key switch, the throttle lever is moving, but has no effect when the engine’s running. I have read that it may be possible for the plungers to get out of wack when removing the tops of delivery valves but I’m unsure how to address this. I have searched many other forums but have yet to find a solution. Any help would be greatly appreciated.

Welcome to TBN! Where are you located? Updating your profile can help folks give you better advice.

As you were replacing o-rings, I would be inclined to suspect that you have air leaking into the fuel line. Do you have any fuel weeps? How hot is the exhaust getting? Any smoke?

Photos might help.

All the best,

Peter

 

[AndrewCrisp]

Welcome to TBN! Where are you located? Updating your profile can help folks give you better advice.

As you were replacing o-rings, I would be inclined to suspect that you have air leaking into the fuel line. Do you have any fuel weeps? How hot is the exhaust getting? Any smoke?

Photos might help.

All the best,

Peter

I did my best to tighten everything back down tight, I haven’t noticed any air getting into the lines it’s just getting way too much fuel.

 

[ponytug]

Well, I've run into air leaks in a number of diesel engines, and it is usually not pretty. That you were replacing o-rings makes me suspicious, but you are right, something might have gotten knocked while the plungers were being worked on. Is it possible that the lines weren't fully bled of air?

All the best,

Peter