I had the same problem - saw wouldn't shut off. The metal terminal on the end of the black wire had slid along the groove. Pushed it back with blade of screwdriver so that it now contacts with the spring on the kill switch and hey presto!
Carver
October 2013
I have the same problem with my ms180 - it won't stop unless I choke it. I have had a look inside the cover and the black lead with the ferrule crimped on it is firmly clipped into the top of the black plastic on/off lever.
But how can this possibly work? The plactic lever is obviously an insulator - is there another bit that makes contact with the earth when the switch is pushed up?
Dave J
February 2010
I had this on my MS180.
Take the top/rear orange cover off.
You will probably see a loose black wire with an end ferrule crimped on, this earths the coil to stop the motor.
it should be cliped into to the top of the black plastic off/on/choke lever, but the moulded in jaws that form the clip don't hold securely hence it comes adrift.
I've put araldite one mine and it's worked ok for the last year or so.
Rob Laird
September 2009
If you take off the top and left side covers, you'll see the plastic mechanism that earths out the coil, shutting off the motor. This has to be perfectly clean to work, but sometimes the electric wire gets chafed through. The mechanism is a bit iffy at the best of times and needs really careful assembly. The good bit though is that it only goes together one way! Tip? Keep a spare felt air filter element handy, and change it frequently - a crushed one lets the grot through.
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