Bobcat 331 Won't shut off

[milkcreekconstruction]

Hi guys. I went to shut my 331 off the other day and when I shut the key off and pulled it out the engine kept running. Is that a faulty ignition switch? Finally the engine shut off after 30 minutes of messing around with different stuff. The 20amp fuse to the start circuit blew which appears to be what shut it down. Even though pulling the fuse earlier had no effect. That again points to a faulty ignition switch right? What is the best way to shut down a diesel when the key won't do it? I tried choking the intake but couldn't get a good enough seal to make it stop running. Any help would be greatly appreciated.

Thanks

 

[ruffdog]

Many of the fuel shut off solenoids are on when power is to them so maybe it was stuck? Here is some reading.
https://www.google.com/?gws_rd=ssl#q=bobcat+331+fuel+shut+off+solenoid

 

[milkcreekconstruction]

Good point! This machine had been sitting for four years. It has a few sticky parts. I'll check it out. Thanks.

 

[SSdoxie]

If dash lights or guages turned off with key, then problem not likley in ignition switch. The fuel solenoid is power on, spring loaded off. It uses 2 circuits for on. 1st is high amp pull that is only on for about 3/4 second this goes through a timer & relay, if timer or relay stick power is there continuosly and will eventually short the solenoid internally. 2nd circuit is low amps to hold solenoid after the high amp pull it to ON.
One possiblity is: Relay stuck on sending constant high amp to solenoid thrugh the Pull circuit, this eventually shorted out the solenoid and the fuse allowing it to shut off. The pull circuit takes voltage directly from battery power, through fuse, through the relay, and back to solenoid.

 

[Navasot]

To answer the question about shutting one down. just put it in the highest gear you got and dump the clutch... not ideal but hey neither is the key not working.

 

[milkcreekconstruction]

If dash lights or guages turned off with key, then problem not likley in ignition switch. The fuel solenoid is power on, spring loaded off. It uses 2 circuits for on. 1st is high amp pull that is only on for about 3/4 second this goes through a timer & relay, if timer or relay stick power is there continuosly and will eventually short the solenoid internally. 2nd circuit is low amps to hold solenoid after the high amp pull it to ON.
One possiblity is: Relay stuck on sending constant high amp to solenoid thrugh the Pull circuit, this eventually shorted out the solenoid and the fuse allowing it to shut off. The pull circuit takes voltage directly from battery power, through fuse, through the relay, and back to solenoid.

Thanks Dennis. That sounds right. Now if only my multimeter was working properly! Well off to the autoparts store for a new one. I'll let you know what I find.

 

[milkcreekconstruction]

So it looks like an intermitant problem now. I did find a few chaffed wires going to the fuel solenoid. I taped them up and haven't had a problem since but I haven't been running it much either. I did check the fuel solenoid and timer for resistance and it seems to have checked out ok. Hopefully it was just those wires...I'll write back if I start having problems again.

 

[ruffdog]

Alright! Good luck with it. :thumbsup: