Bobcat 250 blowing f1 fuse

[Posty23]

Ok I will check that thanks.

[J-Mo]

You might check for a voltage drop on the oil pressure switch... my 225nt did this very thing and I learned that I was only getting 9vdc from the oil pressure switch. Replaced the switch and she started idling again! Good luck!

[Posty23]

Solenoid is attached to the linkage.

[duaneb55]

Hour meter has nothing to do with the auto idler.

Is the "solenoid near the carb" on the carb or attached to the liinkage?

Power to the idler solenoid comes from terminal "C" on the idler module and not the ignition switch.

Power to the hour meter comes initially from the START signal and then thru the oil pressure switch from the RUN circuit.

[Posty23]

So I thought my troubles were over cause unit is running well. But now when I switch to low idle the darn thing doesn't idle down. It was working before but I would have to switch it back and forth to idle twice then it would idle down. Had a spare key switch and out it in, not the proble. Traced wiring from key switch to hour meter read out, then back to the solenoid near the carb. Solenoid has high resistance at 30ohms, but I'm also not getting any voltage to the solenoid when switched to idle. Does the hour meter control that? And is it looking for another input before it allows voltage to the solenoid? I also put 12 volts to the solenoid from the battery just to see if it would pull in, won't even move the linkage. But I want to make sure I can get voltage at solenoid before I replace it. Anyone got anything?

[ryanjones2150]

Huh, what a catchy name they have for their app.

[Posty23]

Strobe tachometer/ timing light.

[ryanjones2150]

What's the app called?

[Posty23]

Yah it's pretty cool.

[duaneb55]

Awesome job on the troubleshooting and fix.

Thanks for reporting back.


A tachometer app on your phone? Strobe? Have to look into that.

[Aeronca41]

Fantastic! Success is good!

[Posty23]

Ok so I went through the wiring again at the diodes and traced all the paths per the wiring diagram. Found that I had actually crossed two wires in the diode blocks, now no more blown fuses. I cleaned the slip rings with coarse then fine grit. One of then was a lot rougher than the other. Once those were good I was getting almost 4 ohms between the two. Then I got a tachometer app on my phone. Measured the engine speed and it was way off. Adjusted to the speed the manual recommends and checked my voltages and low and behold I'm getting my correct voltages at the outlets again! Thanks for all your help, I'm great full that the welding community is willing and able to help others.

[duaneb55]

Some VOM meters aren't that accurate down low but try cleaning the slip rings with some 320grit sand paper and recheck.

Go to Home Depot, Lowes or Harbor Freight and pick up a Kill-A-Watt meter that you can use to check the frequency of the auxiliary power output. Should have 62-62.5Hz for the correct no-load RPM. Adjust governor speed spring as needed.

[Posty23]

I'm getting 7 ohms across slip rings.

[Posty23]

My reading was putting my leads on the wire connection points that go to the brushes. I will take one on the rings with brushes lifted.