Bar Sprocket Locked Up?

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

CutaLot

ArboristSite Lurker
Joined
Sep 23, 2009
Messages
16
Reaction score
1
Location
PA
Never had this happen before, in many years of running saws. 290 Stihl with 20" bar. One year old, not used hard. Chain is in good condition and was adjusted correctly, with plenty of bar oil.

Had just finished cutting down a 12" dead locust when the chain locked up on the bar. Checked all the normal causes and could not get it unlocked.

Took the chain off the bar and the nose sprocket would not turn. Took a firm rap on the handle of a screwdriver, with the blade resting on a sprocket tooth, to break it loose. Sprocket spun freely soon as it came loose.

Is there something going on here with bearings/bushings or whatever, that is going to cause me problems down the road? I did not think that wood chips stuck in the sprocket area would cause this.
 
I've had them split at the tip and the chain gets wedged between the sprocket and the side of the tip. Some bars have a place for you to grease the sprocket. Its just a small hole on the tip and you need a special greasing tool. The good thing about most bars is that the tips are replaceable.
 
Stihl bar has no hole for greasing. Everything looked good in bar tip area.

Wood chips lodged in the sprocket area was my first thought, even though that has never happened over many years of cutting.

Also, since the sprocket "broke loose" immediately after hitting it with the screwdriver, made me suspect wood chips were not the problem. Usually, with a chip blockage somewhere on the bar, the chain comes loose gradually.
 
I drug the chain across the dead locust many times. Always worked on chip dams before. Could not get the chain to budge. I do not think it was chip problem.

Thats why I suspect a problem with the bearings/bushing? in the sprocket. Just trying to avoid a mechanical problem in the future when I am out on a big wood cutting day.
 
I had an oregon get locked up so bad with chips bucking a big oak from both sides when it came apart wedged chips in it I had to take pliers and pull some of the chips out before I could get the sprocket broke loose.
 
The same problem MS 290

I thought I was the only one that had issues with a Stihl bar and sprocket. It seems like I can't even run through a tank of gas without pulling it apart and freeing up the sprocket. Mine always seems to have a bunch of real fine sawdust in it I have sprayed it with different stuff and still the same ole, BS.
My old Poulan 330 still out performs this thing and it's 15 years old and been thru hell and the Stihl is brand new.
Does Oregan make a bar for one of these Stihls?
 
I thought I was the only one that had issues with a Stihl bar and sprocket. It seems like I can't even run through a tank of gas without pulling it apart and freeing up the sprocket. Mine always seems to have a bunch of real fine sawdust in it I have sprayed it with different stuff and still the same ole, BS.
My old Poulan 330 still out performs this thing and it's 15 years old and been thru hell and the Stihl is brand new.
Does Oregan make a bar for one of these Stihls?

Try a duromatic bar instead,no sprockets to get jammed on them:greenchainsaw:
 
I had an older bar tip freeze up once. Broke it loose and it's been fine since. I never did find what was jammed in it.
 
You didn't get the tip pinched at all did ya? Even slightly?

That's what happened to Twinkle's bar. Then Faller Bob showed up and ran it back and forth on the road, after telling me not to be alarmed. Faller Bob said the sprocket needed gunk cleaned out. I have since spent some time in the shop, and got it so it spins easily.

I'll keep it for a spare, although the Oregon bar just doesn't look well on Twinkle.
 
.


Many times the nose sprocket getting jammed is the result of a dull chain. The fine dust finds its way into the groove, then packs into the tip. A sharp chain throws big chips that are harder to get under the chain.


.
 
i just bought a new oregon bar and chain for my poulan 3400 cut one branch and the chain poped off and messed up the drive teeth i filed them down and then ran the saw now the tip locked up solid there are no wood chips lodged is there any way to free it up or do i need to take it back and try to get my money back
 
i just bought a new oregon bar and chain for my poulan 3400 cut one branch and the chain poped off and messed up the drive teeth i filed them down and then ran the saw now the tip locked up solid there are no wood chips lodged is there any way to free it up or do i need to take it back and try to get my money back

You sure you have the same pitch chain and sprocket tip?
 
Easiest way to free them up is with the chain on the bar. Dig the chain teeth into a log and pull the saw backwards. Most likely there is something jammed in it even if you can't see it.
 
the bar and chain where in the same package and i tried that its so stiff it wont hardely move using a hammer and screw driver im no dummy when it comes to chainsaws i used to cut firewood and worked in the log woods running saws
 
Last edited:
the bar and chain where in the same package and i tried that its so stiff it wont hardely move using a hammer and screw driver im no dummy when it comes to chainsaws i used to cut firewood and worked in the log woods running saws
If you bought it at Lowe's or a similar 'big box store'...

Take it back for refund or at least exchange..!!
:cheers:
J2F
 
Back
Top