Could be simply sawdust in the trigger area. The trigger switch, itself, is likely enclosed, but junk and gunk could be holding the trigger on. Before ripping into the handle to replace a possibly defective trigger, try blowing it all out in that area with an air hose while working the trigger on and off. (unplugged, of course)
gotta disagree with you on this one willie, i just replaced the switch on my CM saw recently. the switch is sealed, and the handle is sealed pretty tight too. more than likely it needs a new switch. i ordered one from toolbarn.com for about 20 bux.
(be sure to check the wiring order on the new switch! the one they sent was wired different than the original!)
i'm not saying cleaning it won't work, of course, that COULD be all it needs. but if you click it on and off a few times and it still does that, most likely it'll need a new switch, or keep plugging it in when you need it. if it won't move/click, then a buildup of gunk could be keeping it from shutting off, though i think it'd be easy to tell the difference. but i'm merely voicing my own experience. let us know what happens?
heck, i'm HOPING i'm wrong on this one guys, it'd certainly be easier and cheaper for the OP! (you know me, cheap and easy... hehehehe)
but if he has to get a new switch, here's the difference i ran across with the new switch's wiring pattern. be sure to look closely!
I had the same problem with my Hitachi C10FCH miter saw. I replaced the trigger switch in 2011 (part 322-913) for about $10. In August 2020, I had the same problem but now I found that the part was discontinued -- with no substitute part # given. With some research, I found a part that worked: A "Premium Mini switch, 25A, SPDT, Pin Plunger" from Grainger (part 24A273) for $3 (with me picking it up in the store).
NOTE: This part seems to work in my case...It is NOT an official replacement, but for 3 bucks, it is worth a try. (FYI, the pin-outs were exactly the same as for the failed micro switch).
NOTE2 - I am aware that the discussion is old, but this thread was the only one I found that helped.
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