Problem with chain binding up on new Jonsered

JJ · March 22, 2009, 05:44:37 PM

Hi,
I have been running my Jonsered 2051 for 15 years, and needing 20" bar went saw shopping.

Come home with brand new Jonsered 2165, and really happy how it eats 20" logs (My wood this year is larger than average).

But it keeps binding up on bottom of bar. Usually when saw cuts through log, and gets little pinched by the log. Is sawdust causing it, or is this from the torque of larger saw?

I never have this problem with the smaller 2051.

Will it help to make chain tighter? I usually tighten it until I cannot lift and clear the bar with the chain guide in the middle of the bar.

Since it is 20" bar, I think I am making the chain tighter than the older saw, which has 18" bar.

JJ

ladylake · March 22, 2009, 05:58:50 PM

I have touble with sawdust getting between the chain and bar sometimes, most times on larger softwood. Try and keep the chain turning a little after the cut helps. Steve

Rocky_J · March 22, 2009, 08:07:11 PM

Sounds like either the chain is too tight, the oiler isn't turned up enough or both. The rule of thumb for chain tension is "No sag, no drag". You should be able to spin the chain on the bar by hand without it dragging, and it should be snug enough not to sag down off the bar. If it isn't sagging and it isn't dragging, then it's correct. Anything more involved than that is overcomplicating matters.

John Mc · March 22, 2009, 09:19:08 PM

Quote from: JJ on March 22, 2009, 05:44:37 PM
But it keeps binding up on bottom of bar. Usually when saw cuts through log, and gets little pinched by the log.

I'm not sure I'm following your description here.

Does the saw cut OK when you are just starting the cut, but then get bound up or pinched when the back side of the bar enters the log? If so, this can be due to a bent bar or unevenly worn rails.

John Mc

isawlogs · March 23, 2009, 04:56:41 PM

This being a new saw , I am assuming it is a recently bought new saw , bring it back to the dealer and have them fix the issue , it could be the bar , could be lacking oil could be you are over tentionning the chain. If the bar is straight , and chain is not over tightened .. then either you have the wrong bar or chain , or you have not enough oil going on the bar , both should be taken care of by the seller .

JJ · March 23, 2009, 08:25:32 PM

Hi,
Last times it binds up is with cutting big log, and top of saw chain gets pinched by log. Bottom cuts through without pinching, but when log falls, it gets kitty cornered by other loose log; pinching top of saw.

Slicing through big log is no problem. I also see no evidence of excessive sawdust or heat in bar.
I think that the falling log pinching top of bar (cutting near snow level) gives chain a snap @ full throttle and torque; and locks up chain along bottom of bar.
After bind-up, I can pickup chain on top of bar, but on bottom I have to pry out of guide with screwench

from comments which are very helpful, I am defiantly over-tightening chain.
And I will talk to dealer if keeps happening (2 year warranty)

JJ

Kevin · March 23, 2009, 09:40:41 PM

You might try a full skip chain.
Just a note of caution, if you tighten the chain while it's hot when it cools it could damage the shaft/seals because it will be considerably tighter.

thecfarm · March 24, 2009, 07:43:52 AM

I'm no expect,but I would like to be beside you when that happens.
One of your comments has never happened to me,

Quote from: JJ on March 23, 2009, 08:25:32 PM
After bind-up, I can pickup chain on top of bar, but on bottom I have to pry out of guide with screwench

Can you take the saw into the dealer the way it is in the quote above.I know he would like to see it like that.I do have the pinching problem as you have,but never had a chain do that to me.I would go back to the dealer to make sure things are right with the saw.You mentioned you had a Jonsered for 15 years so you must know how to run a saw.I can't see how it can be the bigger saw fault.You say it keeps binding up on the bottom of the bar.I feel there is something wrong that is not your doing.Take it back and have him help you.Let us know what happens.I sure would like to know.

John Mc · March 24, 2009, 09:40:05 AM

If it's a laminated bar, is it possible the laminations are coming apart (or rivets working loose) and the two side rails are spreading, allowing the chain to suck up in between the side rails?

Just guessing here... I've never experienced anything like what JJ describes.

Rocky_J · March 24, 2009, 05:39:29 PM

No, it sounds like just the opposite. I suspect the bottom rail has been smashed or squeezed and it's too narrow for the chain drivers to fit. Find the narrow spot in the bar groove and use your scrench to widen it back out straight. It will be where the purple spot is on the bar (from the heat).

This isn't warranty, it is user error. Although a good dealer may just help you out in order to make you happy. We all get pinched once in a while but it still isn't the saw's fault.

Al_Smith · March 24, 2009, 08:01:47 PM

The easiest way I've found to find a pinch in a bar is to put the bar in a vise and run the chain around to find the spot .Then open it up .If it tossed a chain it could have a few bent drivers also .

cheyenne · March 24, 2009, 10:29:37 PM

Imho it's probley a pinched bar or your drivers are booggered. I would also check the drive sprocket it may be booggering your chain. I would also check the gap in the bar to the width of your drive links to make sure their the same same.If everything checks out OK take it back....Cheyenne

SawTroll · March 25, 2009, 09:10:27 AM

Quote from: Rocky_J on March 24, 2009, 05:39:29 PM
No, it sounds like just the opposite. I suspect the bottom rail has been smashed or squeezed and it's too narrow for the chain drivers to fit. Find the narrow spot in the bar groove and use your scrench to widen it back out straight. It will be where the purple spot is on the bar (from the heat).

This isn't warranty, it is user error. Although a good dealer may just help you out in order to make you happy. We all get pinched once in a while but it still isn't the saw's fault.

I think you nailed it!!

JJ · March 29, 2009, 11:30:24 AM

Hi All,
This is brand new saw, never pinched.
I inspect whole bar and chain and driver, and cannot find any problem.

Bar is perfect; no pinch spots, no burns, no burrs.
Chain, spur, and bar are correctly matched.
Bar 20" with 3/8"-72 right from Jonsered factory with Oregon 73x72 chain (I have several chains).

Anyway it only binds up on large (18-20") beach logs, and is definitely the sawdust causing the bindup.
I find it (saw chips) jammed under chain on top and bottom of bar. Chain on bottom of bar is snapped tightly to bar by saw torque.

To free the chain, I loosen the bar and pick the chain out of grove until I can move it by hand to clear the chips.

I am cutting up just as large oak logs, and saw has not binded up on the oak (?).

What happens (and I am the one holding the saw) is as chain exits bottom of log, the chain on top of bar grabs wood, and I think gets lifted from bar; allowing sawdust to fill the bar groove, which then travels around the bar at full throttle, being pushed by the drivers. The bindup happens almost instantly.

I do not know how the dealer can help, as I cannot find any problem with the saw.
Lately I have been slowing down at the end of my cuts on the large logs (to about 1/2 throttle) and so far have been avoiding the binding.

JJ

arojay · March 29, 2009, 12:12:56 PM

Flip the bar over and see what happens.

beenthere · March 29, 2009, 01:47:09 PM

I suspect you will discover the problem, as you use it more. I'd make a guess that it is "technique" more than any problem with the saw or bar/chain design. Don't get discouraged, and experiment a bit so you can let us know what is happening.

I've experienced the same (at least from your description) thing with my MS361 - 20" bar Stihl. I now know what I do to clog it up.

Kevin · March 29, 2009, 02:51:01 PM

You might try a full skip chain

Rick Alger · March 29, 2009, 04:46:40 PM

Check the viscosity of the bar oil.

JJ · March 30, 2009, 09:32:33 PM

Hi Kevin,
Will full skip chain slow me down?
Only reason for the bigger saw is to get-er-done quick.

JJ

Kevin · March 31, 2009, 07:25:07 AM

Full skip won't slow you down, it clears the sawdust better than standard chain.
It's the best for the bucking you are doing but be careful limbing with it because the potential for kick back is greater .

arojay · March 31, 2009, 12:32:12 PM

I don't know if you have flipped the bar yet, but there is no cheaper way to diagnose the bar. I have been told that skip is only recommended for bars over 24". I only use it that way and I have to add that skip is noticably slower when bucking dry wood, as in seasoned or standing dry. I use it for felling green and there are advantages as noted. I'm not sure that I agree with buying a skip chain to solve your problem without some further investigation into what's causing the binding.

beenthere · March 31, 2009, 01:34:26 PM

Quote from: JJ on March 29, 2009, 11:30:24 AM
Hi All,
.................
Anyway it only binds up on large (18-20") beach logs, and is definitely the sawdust causing the bindup.
I find it (saw chips) jammed under chain on top and bottom of bar. Chain on bottom of bar is snapped tightly to bar by saw torque.

To free the chain, I loosen the bar and pick the chain out of grove until I can move it by hand to clear the chips.

I am cutting up just as large oak logs, and saw has not binded up on the oak (?).

What happens (and I am the one holding the saw) is as chain exits bottom of log, the chain on top of bar grabs wood, and I think gets lifted from bar; allowing sawdust to fill the bar groove, which then travels around the bar at full throttle, being pushed by the drivers. The bindup happens almost instantly.
......
JJ

That helps to know that the binding is caused by saw/chip dust plugging the groove. Rules out a lot of the suspected problems.

ladylake · March 31, 2009, 03:20:50 PM

As I mentioned above, keep the chain turning for a second or so after you stop making chips if you need to stop in the middle of a log. That give chips a chance to clear. Steve

Kevin · March 31, 2009, 06:54:05 PM

QuoteI have been told that skip is only recommended for bars over 24".

If the bar is buried in wood it doesn't matter how long it is, the chain can't clear the sawdust although longer will be worse.

John Woodworth · April 03, 2009, 05:55:47 AM

Iv'e scratched my head on this one and if the bar is not damaged in any way I wonder about your filing of the chain, I assume you are using full comp. are you taking the rakers down as you file, if you file the cutters and don't thouch the rakers you start getting more of powder than chips as well as slower cutting.
Try using 30 degree tooth angle and lower your rakers a even number of strokes to each raker with a slight downward angle to the front of bar.
Once you try full skip you will never go back to full comp. more chain speed, faster cutting, fewer teeth to sharpen, just be carefull getting adjusted to it as they do buck especially when boring with tip.
I run full skip on the 026 with 20'' bar that I carry in back of skidder and it's a cutting fool for a saw it's size, try it you'll like it.