Murphy Switches.

[canadianclimber]

Murphy Switches. I need a little education.

What's there purpose? How often do you guys go through them?

I'm about to replace my 3rd over 300 hours. So I'm averaging about 100 hours a switch. I've only seen it work when the engine gets too hot and shuts down. Any other things it protects? What about oil pressure?


Chipper would only run if I held the switch in. Engine wasn't hot and oil pressure seemed the same as always. Was running great apart from the switch. Pain in my ass.

Thanks

 

[sotc]

Never lost one yet. But Murphy switch... I could use one of those on this site...

 

[CurSedVoyce]

Like Minds

 

[MasterBlaster]

Lordy!

 

[flushcut]

A willow switch perhaps

 

[Altissimus]

Hehehe

 

[sotc]

😂😁

 

[canadianclimber]

Hmmm. This thread has gone in the wrong direction.

 

[sotc]

Sorry, I was being funny. I've never had an issue that I can recall with thousands of hours. Are you using the same brand of switch every time?

 

[canadianclimber]

Thanks. Same brand every time. Same that came with the chipper(morbark). To be honest I don't mind switching them out, just want to make sure I'm not missing another problem. That's why I was wonder what the switch all protects.

 

[FireFighterZero]

Could it be the vibration that is killing them?

Might move it.

 

[sotc]

The switch just bypasses your gauges. If you look inside your oil pressure and water temp gauges you'll see the needle and a short post. The post in the oil gauge is the main one. When you hold the button in the chipper will run when there is no oil pressure. As soon as the needle leaves the post you can let go of the button. The water post is on the high side of the needle, if the temp gets high enough for the needle to hit the post the engine shuts down. Good safety to have in place

 

[treebilly]

I've never had a problem with them either although I might need to replace the one on my 1250 bc so I can sell the thing.

 

[canadianclimber]

Heres a couple pics. I understand the Temp gauge and the pin that stops it from overheating. But don't see on for the oil gauge. On is of the gauges the other is where the oil pressure sits when running.

 

[sotc]

Hmm, I'd look in the back and see if there's a wire hanging. Someone may have replaced the gauge and that wire may be floating around sparking and shorting...

 

[sotc]

In the current format, there's no reason to push the button to start the machine. Murphy is running loose and outta control

 

[canadianclimber]

Switched it out. The old one didn't look to be functioning the same as the new one. Still a pain. See how long this one lasts. Thank for the help


As well just talked to a murphy switch dealer. Apparently I have the wrong switch. There is an anti vibration version switch. I just assumed morbark would have put the proper switch on when I bought it so I kept replacing it with the same one.