M923A1 won't shut down using switch

[Marine82]

Hello All,
I recently rebuilt the IP on the NHC 250 and put a new fuel solenoid on. I can no longer shut the engine down unless I use the knob on the solenoid itself, using the starter switch no longer works. Any help please!!

 

[simp5782]

Did you get a 12v or 24v solenoid? 12v one will burn out in minutes and will stick the magnet on

The knob should be out for normal operation and only used in a solenoid power failure

The knob in the switch will not shut it down

 

[Marine82]

It's supposed to be a 24v solenoid. If the magnet sticks on what would that do? It starts normally and obviously the knob on the solenoid does function.
It worked for a while shutting down with the switch. Not sure what you mean "the knob in the switch will not shut it down"

 

[simp5782]

It's supposed to be a 24v solenoid. If the magnet sticks on what would that do? It starts normally and obviously the knob on the solenoid does function.
It worked for a while shutting down with the switch. Not sure what you mean "the knob in the switch will not shut it down"

If the thumb screw is in this overrides the electric part of the solenoid so you have to screw the knob out to shut it down regardless.

You said screw it out to turn it off.

There is an issue with some of the interstate McBee and pai solenoids failing alot

 

[Marine82]

so apparently the electric part of the solenoid ain't working...anyone with ideas to troubleshoot?

 

[simp5782]

so apparently the electric part of the solenoid ain't working...anyone with ideas to troubleshoot?

Nope.

Verify you have 24v to it and no 24v with the switch off and if you do replace it.

Go with a cummins unit

 

[Marine82]

great, thanks very much to all!

 

[Marine82]

Anyone...
I replaced the original alternator with a delco and ran the wires from the alternator directly to the battery. I did a quick check on my 24v connection to the solenoid and could not get a voltage. I will do a more intensive investigation this afternoon to be certain. Is it possible the exchange of alternators could affect the wire to the solenoid and if there is in fact no voltage on that wire for shutdown, how could I rewire it so the solenoid will shut the truck down. Starts normally...Thanks!

 

[Crf450x]

Anyone...
I replaced the original alternator with a delco and ran the wires from the alternator directly to the battery. I did a quick check on my 24v connection to the solenoid and could not get a voltage. I will do a more intensive investigation this afternoon to be certain. Is it possible the exchange of alternators could affect the wire to the solenoid and if there is in fact no voltage on that wire for shutdown, how could I rewire it so the solenoid will shut the truck down. Starts normally...Thanks!

Switch on, the solenoid should have 24v. Switch off, there should be no power at the solenoid. If that's what you have, the solenoid is bad.

 

[Marine82]

Thanks very much!