3120xp with 36" bar makes strange noise at the sprocket

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awhitaker

awhitaker

New Member
Joined
Aug 31, 2015
Messages
3
Location
Good Water, MO
Bought a fairly new 3120Xp with no bar at a good price to use as a milling saw. Got a 36" bar and chain put them on and tried to run the saw on the mill today. After getting the bar and chain on ran it and it has a strange whining sound coming from the sprocket/clutch. Spun the chain ok so I put it on the mill. Tried to do a cut and it wouldn't turn the chain in the wood. Took it out of the mill and it wouldn't turn the chain. Tension seemed ok, not too tight nor loose. Took the chain and bar off and it would run good and clutch/sprocket turned. Upon inspecting the chain and bar, the chain has a couple of drive links blued from heat and tips slightly upturned. The bar at the bottom end shows to have gotten hot. Question is, what is going on? Not adjusted correctly? Sprocket has 7 slots so I'm assuming .404 and that's the chain I'm using. Also have a new .404 sprocket that I can put on it. But the whining noise, any ideas? I'm not a novice at chainsaw use, but never used anything this big. I'll take any help you offer!
 
Sierradmax

Sierradmax

ArboristSite Operative
Joined
Mar 18, 2013
Messages
297
Location
RI
Are the bar and chain of the same gauge & pitch? Does the sprocket move freely? Does the saw run WOT when on wood but not turning the chain? Or does it bog down like it's restricted? Perhaps the "fins" on the clutch drum are worn out and the rim sprocket engages at idle but cannot under load.
 
nstueve

nstueve

Makita Freak!
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Oct 22, 2010
Messages
4,772
Location
Iowa
Are the bar and chain of the same gauge & pitch? Does the sprocket move freely? Does the saw run WOT when on wood but not turning the chain? Or does it bog down like it's restricted? Perhaps the spurs on the clutch drum are worn out and the rim sprocket engages at idle but cannot under load.

fixed that for you.
 
awhitaker

awhitaker

New Member
Joined
Aug 31, 2015
Messages
3
Location
Good Water, MO
Are the bar and chain of the same gauge & pitch? Does the sprocket move freely? Does the saw run WOT when on wood but not turning the chain? Or does it bog down like it's restricted? Perhaps the "fins" on the clutch drum are worn out and the rim sprocket engages at idle but cannot under load.
Yes, bar and chain same gauge and pit
Are the bar and chain of the same gauge & pitch? Does the sprocket move freely? Does the saw run WOT when on wood but not turning the chain? Or does it bog down like it's restricted? Perhaps the "fins" on the clutch drum are worn out and the rim sprocket engages at idle but cannot under load.
Same gauge and pitch. Sprocket moves freely. Didn't try on wood and the saw didn't act to bog down. I just put a new sprocket and drum on and tried it in wood and it worked but still makes the noise like the chain is too tight. Even with the chain loose, it still makes that noise. And it doesn't free-spin much when I release the throttle.
 
Marshy

Marshy

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Jan 19, 2014
Messages
6,306
Location
Mexico NY
Mount the bar and chain without the sprocket cover, just use the bar nuts directly on the bar. Set the chain tension and spin the chain by hand to check for binding of the chain. If there is none after rotating through the entire chain then start the saw and blip the saw and watch. You might need something to take up the space that the clutch cover would take...
 
tacomatrd98

tacomatrd98

ArboristSite Guru
Joined
Jan 17, 2008
Messages
675
Location
Newville, PA
Not trying to insult your intelligence but make sure the chain is actually on the sprocket and not down beside it between the rim and the drum. I have seen this quite a few times on used saws. It will spins the chain a little bit with no load but make a weird sound but it just slips if you would actually try to cut like that.
 
Marshy

Marshy

285 Killa
Joined
Jan 19, 2014
Messages
6,306
Location
Mexico NY
Not trying to insult your intelligence but make sure the chain is actually on the sprocket and not down beside it between the rim and the drum. I have seen this quite a few times on used saws. It will spins the chain a little bit with no load but make a weird sound but it just slips if you would actually try to cut like that.
And it would blue only a few links where it was slipping enough.
 
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