Chain wont stop at idle even after adjusting

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To close the idle screw, I will have to turn it clockwise, right? Meaning tightening it?
MAtt93eg, if it is the springs, I found new genuine one sold on their own, so wont need to change all, just the springs, just not sure how easily those can be removed and installed.
 
To close the idle screw, I will have to turn it clockwise, right? Meaning tightening it?
MAtt93eg, if it is the springs, I found new genuine one sold on their own, so wont need to change all, just the springs, just not sure how easily those can be removed and installed.
Yes clockwise gently till it stops. Then 1 full turn counter clockwise. Page 40? of the manual.
 
The clutch bell sits on the shaft of the motor. There is supposed to be a needle bearing between the shaft and the clutch bell. Without that bearing or a bad bearing, it is possible for there to be enough friction to keep the clutch spinning.
Can you spin the clutch bell easily with the saw not running?
 
The clutch bell sits on the shaft of the motor. There is supposed to be a needle bearing between the shaft and the clutch bell. Without that bearing or a bad bearing, it is possible for there to be enough friction to keep the clutch spinning.
Can you spin the clutch bell easily with the saw not running?

This is a once a year maintenance item for me. Supposedly the needle bearings are low duty and don't require lube, but I put a dab of 3-in-1 oil on it anyways. Something else to investigate...
 
To close the idle screw, I will have to turn it clockwise, right? Meaning tightening it?
MAtt93eg, if it is the springs, I found new genuine one sold on their own, so wont need to change all, just the springs, just not sure how easily those can be removed and installed.

Right, if you can find just the springs your good. I found a new clutch for a good price that was OEM for my 6401 so I just bought the whole thing.

It sure is nice that it is fixed. When the chain continues to spin it just pumps oil the whole time unless you hit the chain brake.
 
In manual it says that I should use the locking screw to stop the piston so that I can unscrew the nut holding the clutch. Problem is that I do not have such a locking nut. What else can i use to block the piston, so that it does not move in the cylinder and get the nut loosened.
 
I use a piece of 1/4" cotton rope to stop the piston - put a few inches in through the spark plug hole as the piston is coming up. Make sure the piston is above the exhaust port so the rope doesn't get stuck in the port. I had a similar problem with my Stihl trimmer. The clutch weights were sticking. Make sure the weights move freely. One other thing regarding carb setting, The 08s uses a governor for high speed control. It closes the choke plate to richen the mixture and limits speed.
 
In manual it says that I should use the locking screw to stop the piston so that I can unscrew the nut holding the clutch. Problem is that I do not have such a locking nut. What else can i use to block the piston, so that it does not move in the cylinder and get the nut loosened.

What ever you do, DO NOT use the locking screw/piston stop. What works for me is to just use an air impact driver. The rope in the cylinder also has success for many/most.
 
First see if the clutch drum spins freely with the chain off or if it's binding. I just had a saw on my bench that had a worn out washer (behind the clutch drum) so the clutch would only bind after the nut was tightened down. A new washer fixed it. Since the 08S has an outboard clutch, you could also use a cordless impact driver to remove the nut holding the drum on. Always pull the spark plug boot off so it can't start but leave the plug in for compression. Take everything off the crank and look for wear. Inspect the washer under the nut, the sleeve that the bearing rides on, and the washer under the clutch drum for wear. The sleeve can wear a groove in the washer so it pinches the drum when tightened down. Clean and grease the bearing. Replace it if it looks or feels damaged. Clean everything well. Once you have the drum off, the clutch shoes should feel tight on the hub. If they feel loose, you probably need new springs. Clean all the dust and oil out before you re-assemble it. Good luck!
 
Hi all,
have had some time to remove the sprocket and looked at it. I have posted two videos, please check and advice as I am not quite sure. First is about the play of the drum sprocket back and forth. It does spin freely when rotated by hand, just not sure for how long it has to spin freely when given a push. Is this spin normal that you can see on video. The play in the sprocket- Looks like the ring that the needle bearing is sitting on is about 1-2mm longer and the nut that locks the sprocket cannot be tightened enough, to lay against the sprocket
Another thing- I have ran the chainsaw for no longer than 5 mins since I bought it and I am almost sure the ware on the driver sprocket was not there. Is it pssible to appear that quick and what might have caused it.
In the second video I have tested again after assembly. I have only put some grease on the needle bearing and that was it. Springs on clutch looked ok to me, as when i tried to pull any of the three plates of the clutch, I couldn't even lightly move any of them, so I guess they are OK. Also, as you can see from images, clutch is covered in oil, is this normal or it should be clean?

This is how I mount the chain, guess it is correct.
20200106-095901.jpg

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The back of the plate that is between clutch and needle bearing. Actually what you seen on picture, is everything that is under the sprocket. Does it has to be something more? Sprocket seems to be genuine STIHL one, as I can see STIHL logo embed on it.
20200106-093310.jpg


20200106-093242.jpg

20200106-093222.jpg

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As you can see the chain does not stop immediately after releasing throttle.

 
The chain won't stop immediately but should also not stop abruptly as it does. I will open up my 08s for comparison. The clutch should not be coated with oil but that shouldn't br a big problem. On older gear drive saws, the clutch is soaked with oil. That amount of end play looks ok. The wear on the teeth is not new. IMO the sprocket needs replaced. Again, let me open up mine and I'll take some photos.
SEE MY NEXT POST WITH PHOTOS.
 
OK, see photos. The end play was about the same as yours - you can see how much of the inner bearing race is out past the bearing and the drum. The washer and nut tightens against the inner race. The drum should spin freely. You should be able to pry gently on the clutch shoes and they should move a little. The rust tells me they may be binding against the carrier or against the worn areas on the back plate. You may be able to turn the back plate around so a smooth surface is against the clutch shoes. I would clean the oil from the shoes - gently - these do have a lining vs newer clutches that are metal.

20200108_194028-1_resized.jpg 20200108_194112-1_resized.jpg 20200108_194156-1_resized.jpg
 
I just noticed something else. In your third pic, it looks like there is a backing plate behind the clutch shoes. This is not on mine. I haven't owned the saw since new but there is a much smaller plate on mine and I've run it for close to 50 years with no problems. I see now that the wear on the plate in your photo is on the outer plate - my bad.
Try to find a clutch drum with replaceable rim sprocket like mine.
https://www.ebay.com/itm/Clutch-Dru...688489?hash=item2cee9ae0a9:g:5kUAAOSwOMdZTgg7
 
You don't have a clutch problem. All you ever had was a lack of understanding about how to get the right idle setting and from the video, it seems about right now. That drive sprocket is BADLY worn and it looks like a new chain, that sprocket can damage the chain and should be replaced.
 
Thank you, guys. So, at least I know clutch is OK. Should I take it off and check that plate behind it, or not do that?
I was also thinking about the sprocket #buzz sawyer suggest, just was not sure if it fits mine, but now I know it does, and I will get one. It is for 404, right? Also, I see some that are sold by Chinese sellers for a lot lower price- any idea if worth, or better go for the more expensive ones.
#Old2stroke, should I play a bit more with the idle setting? I did as suggested earlier- have tighten the idle screw all the way and then started unscrewing it till chain stopped spinning at idle, and then quarter of a turn more. Also, is the way the chain stops after releasing throttle normal?
Yes, chain is new according to the guy who sold the chainsaw. So, I will get a new sprocket then in order to save the chain. The chain is mounted the right way though, isn't it?
 
If you plan to use the saw a lot, I would look for the rim sprocket. If not, the spur sprocket is fine. My concern with the chain stopping abruptly is at .015 and .045. Maybe tension is a little tight? Is it a sprocket nose bar or hard nose? Mine is .404.
 
No, it will be used maybe few times per year. to be honest, i was thinking to ask about chain tension, as I am not sure if I do it right. I fit the chain and then put the sprocket cover and tighten the two nuts by hand. Then I tension the chain and once tensioned, I tighten the nuts with the wrench. Maybe this is my mistake, as in manual it says I should tension it before I put the sprocket cover back. But I am only doing it so, as I am afraid that bar might come off without the cover as i find it really difficult to place the bar and chain and hold it in place before I mount the cover. As my concern now is more about the chain stopping too slow after throttle released.
It is hard nose I think, havent checked to be honest. It is Duromatic bar- model number 3002 000 9223
 
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