Chain wont stop at idle even after adjusting

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The idle speed should be set just below the point where the clutch starts to grab so yours looks about right and since it accelerates quickly without bogging when the throttle is snapped open means the idle mixture (L screw) is set about right. When it is slow to return to idle after releasing the throttle it could be because the high speed (H screw) is set too lean, this is a whole different issue, have to make some cuts at full throttle to check this. Also make sure the throttle plate shaft in the carb is free to turn and not being sluggish to return to its idle stop. Don't know what's going on with the clutch cover, have to see some pics for that. When adjusting the chain, don't tighten the bar nuts more then light finger tight, then set the tension so that the chain just touches the bottom of the bar just like it does on the top with no sag. Tighten the nuts and check the tension by pulling the chain along the bar. It should move freely, if it doesn't the chain is TOO tight. Always do this check after any chain adjustment.
 
Make sure you lift up on the tip of the bar when setting the tension. If not, the chain may loosen quickly while cutting. also, you will have trouble setting chain tension with the wear on the sprocket. That saw incorporates a governor that closes the choke plate somewhat as the speed increases to control top end speed. Been a while since I set mine so someone else may need to chime in on this. I will see if I can find somethin in the manual.
 
thank you. Yes, I read that before and tried to tension as described in manual, but maybe I missed something. Will take the sprocket cover off again and retension the chain again as now it does not move at all when I try to move by hand.
Old2stroke what pictures do you need, so that I can take some. Will check that with the carb plate as well as soon as I get some time. BTW should I play a bit with the H screw, or leave it for now until tested on wood, which should happen soon as I have some trees to prune/cut. What should I observe about this issue to check if there is any at all.
 
I couldn't tell where the tensioning screw and pin is, but if you are able to adjust the tension with the cover off, it must be on the saw body. When you mount the bar and chain on the saw just make sure the tension adjusting pin fits into the hole in the bar, then put the cover on and secure it with nuts done up with very light finger pressure while making sure the adjusting pin stays in its hole, then go from there with the adjusting as described earlier. If you get it adjusted right and the chain is grabby to move or won't move at all it could be as mentioned that the worn sprocket is just not compatible with the new chain, in which case you should not run it at all. It helps to see what is going on by leaving the cover off and placing some spacers (washers) over the bar studs and setting chain tension without the cover, then as you pull the chain along the bar you might be able to see where the hang up is. Setting the H screw for proper high speed operation is the most important procedure for the longevity of the saw. Do a search for threads about tuning by ear, there are many good ones. When describing what you are doing, it is important that you indicate if it is the idle speed screw or the low speed mixture screw (L) that you are turning.
 
After looking at one of your previous pics, it looks like a lot of slop between the bar slot and the bolts. I need to compare to mine again - doesn't look right.
Also keep in mind that this saw uses a governor system that will limit top end speed. You pretty much have to tune it in the cut, not just running wot on the ground like modern saws. I'm trying to find the exact tuning method but it's not in the shop manual I have.

Good idea about checking with the clutch cover off but since the oil pump is in the cover, it won't oil with the cover off. Shouldn't be a problem for a short time and you couldn't cut anyway since the front handle will be off too.
 

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A couple other things to check. Did you clean all the crud out of the bar groves? If that is a sprocket nose bar, does the sprocket pitch match the pitch of the chain? That is a new chain and it comes in 2 different gages, it is possible it's the wrong one so check to see if the drive links fit right down into the bar grove without jamming.
 
In your photo, the bar is not on the wider area of the bar bolts - see my photo. That's what I was seeing.
Second photo shows the carb and governor set up - air vane on the flywheel that connects to the choke linkage. I would disconnect the choke linkage and set the high side until you hear it 4 stroking, then reattach the choke linkage and set the tension spring to allow max RPMs - I think the manual said 10K but that seems a little high for this saw. There are several holes in the choke arm to adjust the spring tension, but honestly, from your video, it sounded pretty good.
 

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I'm back. See photo. I disconnected the rod from the air vane and set the H screw to 1 turn out, then, while running wide open, I turned in until I hear a strong 4 cycle, about 3/4 out on mine. Tach read about 9000 rpm. I then hooked up the air vane rod and moved the spring to the top hole to reach about 8000 rpm with no load. You have to remove the plate to change spring position. More tension on the spring restricts the ability of the air vane to close the choke plate. Unfortunately it started to rain hard so I didn't get to try it in wood but based on the setting with the rod removed, I sure it will be fine. One other note - while my chain didn't stop quite as abruptly as yours, it did stop more quickly than I expected but then I had no bar oil in it. This is a restoration and I had drained it. That being said, your chain might be a little tight but as long as the clutch drum turns freely, it should be ok. I will try to shoot a video in a day or two when it stops raining.
Hope this helps.
 

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My dealer taught me like Andy says. Low speed screw in clockwise till it almost stalls it gets blubbery. Then turn counter clockwise 1/2 turn out. Done adjust your idle speed. This low speed setting works on most saws without the new stuff in them.
Next do the high speed like Andy says. Once the high speed screw is set the low speed screw may need turning to clear up the circuit.

You may need to do this more than once, that’s ok your learning it.
 
Thanks you all guys for the inputs. Need to say that this is the first forum on the internet, not just for saws, but in general, that guys are so helpful and really willing to help. I am impressed.
I do not have much time to play with the saw, as I am doing a total renovation, but had half an hour today to try re-tension the chain. So, I tried doing it without the cover, but as soon as the chain is almost tensioned without any sag on the underside, the bar comes off the tension pin. buzz sawyer the slop/space on my pic is because the bar fell off the pin. So, I put the cover on and screw the two nuts by hand. Then I started tensioning the chain. Once the underside of it touched the bar(no sag) I moved the chain by hand and it was moving quite easily, i then turned the two screws on the sprocket cover all the way using a wrench. Then tried to move the chain again, but it wouldn't. I then unscrew the two nuts and turned the tensioning screw out a bit so the chain was moving even easier. Then screwed the nuts on the cover with the wrench again and now the chain was moving by hand, but with a bit of force. What I mean is that it needs to be pulled just a little bit stronger to move, but it does move. Now seemed to stopped in a better manner.
To be honest, I am a bit worries about doing anything with the H and L screws, as never done that before and I am not sure if I have the "ear" for that. Is it really neccessary from what you hear in the video, or it is advisory. From what buzz sawyer says, I should first turn the H screw all the way in(clockwise) and then unscrew 1 full turn and then back by 1/4. BTW the guy who sold the chainsaw said it was recently serviced with the carb being tuned, but I am really not sure if this is true or was just a selling practice.

PS when saw is not running I noticed oil drips a bit. maybe a drop or two every now and then. As when I leave it in the storage there is a spot underneath. Is this normal?

PS2 not sure if I have mensioned this on the forum, but, there is a noise I can hear on idle, maybe not noticeable in video, but it is a rattle noise that some say it might be because of clutch problems(that is what I found before on here), but I think it comes from the sprocket. Do you think the wear in the sprocket causes it?
 
H&L screws should not have a large effect on the running of the saw. Just try some counter clockwise, or clockwise and remember how far you turned it so you can set if back to factory if you wish. Normally the low and idle is to get it to idle smoothly and rev properly. The H is use to tune the saw in the cut. Again if you never touch them, then you are in the 98% category of saw owners.

A few drops of oil is nothing to worry about. I had a saw dripping oil, and thought I would investigate it when the weather improved, but it went away on its own. If it something simple fix it, if not don't worry about it.
 
The carb setting sounded good to me in your video. I turned my H screw back in 1/4 turn because that's where it sounded best to me on my saw. This setting can vary in different saws but again, yours sounded good in the video. If you do turn the screws, Turn them in until they just bottom out and count the number of turns - so you can always go back to your starting point.

As for the chain, until you get a good sprocket on it, it will be difficult to adjust it properly but running it a little loose may confirm that it turns freely. Since it tightens up when the nuts are tightened, make sure the bar is mounted on the wide part of the mount bolts as seen in my photo. When you adjust the chain, turn it as you tighten the nuts to make sure it drops into the worn area of the sprocket.

The noise you hear could be coming from the clutch. Some saws I have do this and some do not. Is the air vane governor working? That could also be making a noise if not connected right. Oil drips are not unusual. Some saw drip more than others. When I put them in storage, I drain the oil from those that leak.
 
When the chain is loose, it moves completely freely with just a gentle pull. Only when tightened so that there is no sag on the underside, it requires some more force to get it moving.
Havent removed the bonnet above carb to inspect, so cant say about the air vane governor. Can this be checked without disassembly? Only reason asking is, that I am quite busy now, and only get time for the saw very rarely. Need to check if the sound appears when chain is removed, guess that will clear alot of guesses.
 
To remove the bonnet, remove the spark plug and three screws. To replace it, make sure the throttle arm is in the right position. You need to hold the throttle trigger in the idle position. If there is a shut off button, you may have to remove the retainer to lift the bonnet.
See your photo below - I took a closer look - there is an indentation at the bottom of the teeth - this means the drive links on the chain are bottoming out. This will cause the chain to bind when tightened. You won't be able to adjust the chain properly until you replace the sprocket.

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I see. Good you said that, as I was about to keep it, as not going to use the saw that often. Now, I know I will have to buy a new sprocket. How will I know what sprocket I need? The one like yours, with removable ring- will it be OK? And would it be OK to use the saw with that sprocket for the time being if need to, until new sprocket arrives?
Will try take the bonnet off as soon as I get some more time.
 
Just look for one for your model saw. There are several on ebay. You want .404, 7 teeth. Yes, I do recommend the rim sprocket. Hard to say it's ok to run it. Since the chain is bottoming out, it could damage the drive links if not already done. Look for mushrooming on the bottom of the drive link tangs. Post a photo of the front of your bar so we can see whether it's sprocket or hard nose.
 
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