The chain is already spinning...

maple1 said:

If your saw is working right, the chain won't be turning when you're not pulling the trigger

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...unless the fast idle is engaged, as it often will be when starting a saw.

maple1 said:

...and you can't pull the trigger without your hand fully around the trigger handle to first push down the trigger release thingy.

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...which helps, but doesn't absolutely prevent accidentally grabbing the throttle at an unfortunate moment. Chainsaw users do tend to grip that rear handle now and then, even when they aren't actively cutting.

Obviously the OP needs to get their saw fixed, but a little redundancy in safety measures is a good idea. Locking the brake is sort of like flossing your teeth, i.e. a habit that's hard to establish because it's not any fun, with benefits you never tangibly see no matter how statistically, demonstrably real they are.

Highbeam said:

I think it's a stupid rule that the chain brake ever be engaged as a matter of SOP.

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Agreed

Highbeam said:

The chain should not spin at idle regardless of the existence of a chain brake.

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Also agreed. I'm just being an @$$.

Bigg_Redd said:

Agreed




Also agreed. I'm just being an @$$.

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sometimes its hard to tell.....

Jon1270 said:

...unless the fast idle is engaged, as it often will be when starting a saw.



...which helps, but doesn't absolutely prevent accidentally grabbing the throttle at an unfortunate moment. Chainsaw users do tend to grip that rear handle now and then, even when they aren't actively cutting.

Obviously the OP needs to get their saw fixed, but a little redundancy in safety measures is a good idea. Locking the brake is sort of like flossing your teeth, i.e. a habit that's hard to establish because it's not any fun, with benefits you never tangibly see no matter how statistically, demonstrably real they are.

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All true, yes. Only relating what I have always done. Maybe it could be called bad habits - but everything I have ever done with a saw swings on utmost respect for the trigger. Some might argue that respect might diminish a bit, maybe, with constant reliance on the brake - but I won't.

Need to define a fork in the road: rpm or mechanical.

Is the engine idling faster then normal? Then find out cause of higher idle that engages clutch. Adjust carb or air leaks or switch in correct low idle position.

If idle rpm is normal, then mechanical problem in clutch. Grease bearing and check or replace springs.

Son's 180 was very nice fast lightweight saw.

K

I just took apart the MS290's clutch last night to clean the drum and grease the bearing, check the springs. All those springs being in place and clean is pretty important.

My 361 does this occasionally when the chain gets loose and needs adjustment.
After adjustment, all is well.

Hogwildz said:

My 361 does this occasionally when the chain gets loose and needs adjustment.
After adjustment, all is well.

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As Highbeam said check the needle bearing on the clutch. If the bearing gets dry it can stick and cause this condition. Put a little high temp grease on the bearing and re-assemble it.

All my saws seem to need this every few years so I've just gotten in the habit of doing it once a season before I put the saw up for the winter.

TMonter said:

As Highbeam said check the needle bearing on the clutch. If the bearing gets dry it can stick and cause this condition. Put a little high temp grease on the bearing and re-assemble it.

All my saws seem to need this every few years so I've just gotten in the habit of doing it once a season before I put the saw up for the winter.

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It's been bugging me and since the photo above shows it very well, there are indeed three springs and not just two as I mentioned earlier. If needed, replace them all at once.

i was watching a television show called ''AX-MEN'', and one kid after felling a pretty large pine, stepped back and up onto the stump end of a tree already felled, when the falling tree landed it hit the tree he was standing on and sent him head over toe while holding the saw, and squeezing the trigger....when he landed on his butt the bar landed on his leg then he tried pushing it away with his hand.....he stood up and asked the cameraman, '' you didn't get that did you''........VERY lucky not get cut......not wearing any eye or neck protection and not using the chain brake with those monster saws in those kind of cutting conditions is pretty,,,,,risky

Tighten your chain. Once tight learn the correct finding method. Probably a combination of idle speed and L adjustment.??

Or an air leak if this saw has some hours on it?