I replaced the auto idle control 268-0254 about 4 months ago. It worked fine until this afternoon, New operator complained of no power and would not run above idle. I shut down the machine, turned the throttle dial back to idle, turned the key until the buzzer quit, started the engine, turned the auto idle dile up and the engine turned up to speed but would not auto idle down. Do I need to disconnect the battery and wait 1-2 min and hope for reset? If so positive or negitive post first?
I don't think cycling battery power is going to help. Does the engine speed reduce when you turn the dial down and the only problem is with the auto idle? If so, the first thing I would check is the pilot pressure switch and its wiring. It's located on the top right of the main control valve. With the dial at 10, unplug the switch and bridge the contacts on the harness side. The engine should idle up.
Yes auto idle is the only issue. Throttle dial controls engine speed. I will check out the pilot pressure switch.
I have attached the parts drawing. If I understand correctly I should roll the throttle down, unplug the switch, and jumper the plug and see if the auto idle spools up. If it does I need a new pressure switch?
The pressure switch is what tells the auto idle system to idle up and down, so; Pressure switch - disconnected. Engine - on. Auto idle switch on the dash - on. Throttle dial - 10. Engine should go to high idle for a few seconds then idle down. Jump the terminals in the pressure switch harness plug and the engine should idle up. Remove the jumper and after a few seconds it should idle down. If all this is true then yes, faulty pressure switch. (Could also theoretically be a hydraulic problem with the logic that supplies pressure to the switch, but it's unlikely.)
Cmark, thank you for all your help. My oldest operator showed the rest of us the secret on/off rocker switch at the rear right of the operator seat. Funny how when you turn it on the auto idle works fine. How ever I now know how to trouble shoot for when the pressure switch does fail.
I love those types of repairs
And I bet there wil be nobody who will own up to having moved the switch in the first place .......
If all else fails, RTFM.
RTFB in my world. Same horse, different jockey.
Sounds like the little Detroit engine in a crane at another branch of the company I worked for. After dumping about a case of starting fluid through engine they called in the outfit that had rebuilt the engine a few moths before to "fix" it! After a quick couple checks guy reset the emergency shut-down flapper and it fired right up. But as i recall the starting fluid had done it's damage along with the water getting down the exhaust that the people who had rebuilt the engine had been told to "Don't worry about that we will handle that as soon as it get done with this job!"
The newest operator quit last night so we took a vote and blamed it on him.