I have a Gehl 5635 & while working it one day it began to idle fast. I pull back on the idle lever & it does not change, I pulled up on the fuel peddle & no change. Idling about 300 rpms higher than normal. What would cause this ? Thank You.
Could be external binding between the foot pedal/hand lever cables and the injection pump. If not that, then it could be inside the injection pump from crap in the fuel, or a sticking fuel rail. I forget if you can see the end of the fuel rack on that motor from taking out the shut-off solenoid, but if you can, you can gently work it back and forth to see if that helps. Or throw some Seafoam in the fuel.
I have removed the skid plates and cleaned out lots of soil build up, checked for binding at the foot/throttle lever ( working fine ) and just added some sea foam to fuel. It is a Deutz engine with 1200 hrs so not a ton of hours. Will try and locate fuel rail next. So far, no change in high idle. Thanks
300 rpms is not a lot. Is the stop bracket hitting the idle adjustment screw (if there is one)? I had a 5640 that had mud silt in the bottom pan underneath the motor, dried extremely dense like mortar about an inch thick all underneath the motor mounts. After I got it removed the engine didn't vibrate like it had before. Had another Gehl that sat for ten years with two digit hours on it, the owner couldn't get it started so they took the shut off solenoid out of the IP and took a screwdriver and hammer to the fuel rail.
Yea, it is bottoming out on the idle stop. I had already checked that. And everything is tight on the idle screw as far as it vibrating open some and allowing the higher idle. I said 300 but it maybe as much as 5 or 600 rpms higher. I was moving a pile of top soil from where a pool had been installed in a yard one day and after about 30 minutes into the work it just began to idle faster. Just so you know how it happened. Wasn't shut off and just started up and began to do this. And when I go backwards it seems to idle up just a tad faster ? Probably a simple fix. Thanks for your input !