It had a new PQ circuit board from hindley electronics just before I bought it a few years ago. The reason I ask is when I'm up in the air I have some trouble with my swing control moving to fast and it would be nice if the engine would be at a lower RPM so it wouldn't be so sensative. Is mine supposed to be that way as well or is it working properly when it throttles up as soon as you step on the deadman's switch? When working properly it currently idles (quite low but smooth) when off the switch, when you step on the switch it throttles up pretty high, when you flip on the high engine switch and move the machine it throttles up just a hair more. On another note, I read in a different post when I tried searching about this subject about a different model jlg lift that sounded like it is supposed to stay at the lower idle setting except when it is being driven.

Sounds like the high engine relays might be sticking (engine at high throttle) and when I start to move the machine it pulls the engine down slightly under load. when in the high position it tends to bog the engine down a little bit unless I'm on perfectly flat and solid ground.īack to the original topic, when I use the high engine switch while I'm having the problem with it staying at high throttle it actually seems like the RPM drops slightly when I start to move. Obviously the engine speed controls the throttle, seems like the drive high/low acts like a 2 speed gear switch but I'm not sure how it works, and the motor high low acts like a high or low range for the motors. how exactly do these three switches work? sometimes I get in some soft ground conditions and have trouble spinning a wheel out and have found that certain positions of the switches seem to work better in tough situations. While on the subject it also has, if I remember them right, a 'drive speed high/low' switch and a 'drive motor' high low switch. This machine does have the high engine switch for when driving the machine. any ideas where that is? I've tried tapping on everything I can find to see if something is sticking but haven't had any luck. Sounds to me like possibly a sticking solenoid somewhere that controls the throttle setting. also doesn't seem to be related to any certain activity. This doesn't seem to be consistent as sometimes it will work and other times it won't. When it sticks it just stays in high idle and doesn't allow any of the control functions so that would sound to me like it is working alright between the basket and the main frame. Let up off the switch and it idles back down and you none of the controls work. Normally when you press on the switch it revs the engine up and allows hydraulic control. Biggest problem right now is that sometimes it gets stuck in its' high idle position even when I take my foot off the dead mans switch in the basket. I've got an old JLG 50HT boom lift I use around the farm and it's started having some issues I'd like to resolve.

Jlg boom lift motor