Bobcat 225NT won't idle up

[Rhino684]

Have a miller bobcat 225nt with onan performer 16 propane engine. The unit starts up fine but immediately goes into low idle regardless of position of selector switch. It also won't idle up to weld speed when I strike an arc. I can manually open the throttle and it will rev up fine but immediately drops into low idle when I let off. I have done the following already: changed oil and filter, cleaned propane vaporizer, cleaned air filter, and replaced the idle control module (red box on back of face plate) with no luck. Any help is appreciated.

[rizzo]

Having same Problem

I have a 1996 Miller Bobcat 250 With an Onan 16 Performer. It starts fine but doesn't idle up when the generator is being used or when you try to strike an arc. When started it revs up then when it becomes warm, after I think like a 10 sec timer It idles back down. Welds and generator works but only when in the rabbit position.I thought it maybe the five pin idle module, or the solenoid 2 speed governor. The two speed governer is a part on the Onan engine.

[rizzo]

did some more looking around on the site and found a thread that maybe helpful.

Thread: Bobcat 225G Plus - Won't Come Up To Weld Speed

[Rhino684]

I have a 1996 Miller Bobcat 250 With an Onan 16 Performer. It starts fine but doesn't idle up when the generator is being used or when you try to strike an arc. When started it revs up then when it becomes warm, after I think like a 10 sec timer It idles back down. Welds and generator works but only when in the rabbit position.I thought it maybe the five pin idle module, or the solenoid 2 speed governor. The two speed governer is a part on the Onan engine.

Sounds like the solenoid is working properly if it's idling down after 10-15 seconds. The device that detects a current (arc or using the generator) may be the problem. The solenoid works one way; meaning if there is no current or arc being used , it will tell the solenoid to engage and pull the engine down to a slow idle. When a current is detected, it releases and allows the engine to rev back up to full throttle. There's another thread on here that has a procedure for troubleshooting both the 5 pin module and the current sensing transformer (round red disc). I ended up buying both parts thinking they were my problem when it ended up being the throttle adjustment screw was loose and backing off on its own. I reset it to the recommended RPM's and it's working good now. If you end up needing either of those parts, just message me and I'll sell them cheap.