Stihl 029, chain catching in the bar on the underside

[blthomas]

I'm by no means a total newb, but I'm pretty darn far from a pro too.

I've got a Stihl, like in the title above. Had it since 1998. God knows how much wood she's cut for us and family over the years.

I just picked up a new Rollermatic bar for it as the old bar was worn out.

The chain is pretty new, couple months old, but barely used.

I set this chain up the only way I ever have, and it catches right at the end of the bar, behind the toothed wheel on the underside.

Almost every other cut. Pretty dang irritating when your trying to get something done and you gotta keep dropping the bar to get the chain out.

I looked at the runner teeth to see if they were burred, maybe one or two were and might be catching in the channel.

Doesn't seem so.

Am I running the chain too loose?

Or too tight?

I certainly haven't changed the ways I do things. Not wild or anything while running her.

The bar doesn't appear to be defective, crimped or whatever.

As far as tensioning the chain, here is my procedure, call me on whatever needs to change:

Unset chain brake.

Loosen bar retaining nuts.

Hold up the end of the bar with my freehand, watching the chain, screw in adjustor screw taking slack out until the runner teeth are just about 100% in the bar groove on the bottom.

While still holding up the bar by the end, I tighten the bar retaingin nuts.

Done?????

Any insight would be great. This is my favorite time of year to be out cutting........

 

[ChrisN]

Are you sure that the new bar and the drive links on your old chain match?

 

[blthomas]

Are you sure that the new bar and the drive links on your old chain match?

I haven't the knowledge to really know to be honest.

Can I check visually for a specific thing? It looks OK at a glance.

The shop will close before I can get there today, so I'll have to see about it on my own.

 

[Roospike]

Are you sure that the new bar and the drive links on your old chain match?

That was going to be my question .

Sounds like your doing it right with readjusting the bar.
one thing i didnt here you mention was how you tighten the barn nuts , as a good rule of thumb one should hold up on the end of the bar and hand tighten both nuts to seat them , when you use your wrench to tighten the nuts wile still holding the bar tighten the bar nut towards the engine (the one all the way back ) first and then tighten the barn nut on the right away from the engine.

Normally if your not getting the bar and chain tightly mounted your chain will go loose quickly but that dont seem to be the case.

#1 I would call your Stihl dealer with the #'s on your chain to make sure they match the new bar.

Chains , bars & sprockets are a funy thing , when all new that match correct and after useing them together they all make there own ware together. Now add a new chain,bar or sprocket and it dont always match the others very well.

See what your Stihl dealer says about the bar and chain match first.
clean out the groves in your bar with a thin blade or flat head screw drive to make sure the rail is clear of any junk.

Good luck.

 

[Eric Johnson]

Good advice from Roo. Sounds to me like maybe you're using the wrong bar for that saw. Very little standardization in this industry, which makes it easy to buy parts that don't match up. If you're running .325 pitch, 50-gauge chain, then a bar designed for 72-gauge or 3/8 pitch chain is not going to work.

 

[blthomas]

I talked to my dealer and he may have shed some light.

After a brief discussion and description of what is happening, he asked had my chain ever jumped the bar before I switched the bar out yesterday.

I had stated yes, it had done it a couple times, but I thought it was due to me doing alot of cutting on smaller stuff and being slow to tension the new chain more often like your supposed to.

He said the runners are more than likely beat up a little, and I can file both sides of each and every one, or get a new chain.

I have another decent chain in my toolbox, but I think that one jumped once on me too.

I'm going to see how it does and go from there.

If it binds again, I'm taking the whole saw to a my guy and see what gives. This was the most trouble I've ever had with the saw in almost eight years.

 

[blthomas]

Good advice from Roo. Sounds to me like maybe you're using the wrong bar for that saw. Very little standardization in this industry, which makes it easy to buy parts that don't match up. If you're running .325 pitch, 50-gauge chain, then a bar designed for 72-gauge or 3/8 pitch chain is not going to work.

My last response was mostly on Roo, but I will definintely double check my parts after testing my backup chain.

At my dealer, they are old school, but whenever you make a purchase, they log you into the computer. They pulled my last chain and the new bar off the shelf for me.

But it would make sense if I just got a 18" bar on my own and didn't pay attendtion.

I'll post back after I run it.

Thanks for the help,
Blair

 

[Roospike]

Definitely a good call by the dealer. I had a brand new bar and chain and was stumping a log ( cutting a stump at ground level ) and about 1/4 the way through the chain jumped the bar. I went to put the chain back on and it didnt fit in the rails ......... 4 guides on the chain had burs on from throwing the chain. I had to take my grinder to the guides and tho they worked in the bar they were still tight around the sprocket nose of the bar , took a fine file to them and it fixed the problem .

Throwing the chain is definitely not good on a chain. Hope you found your issue.

 

[MALogger]

If the chain jumped off the bar that usually puts some burrs on the drivers. I have an easy way to fix that, instead of filing both sides of each driver. Loosen the chain so it hangs off the bottom of the bar, not too much but make sure it is loose. Then start the saw and run it wide open for a few seconds. Then tighten the chain back up and test it.

Craig

 

[Roospike]

If the chain jumped off the bar that usually puts some burrs on the drivers. I have an easy way to fix that, instead of filing both sides of each driver. Loosen the chain so it hangs off the bottom of the bar, not too much but make sure it is loose. Then start the saw and run it wide open for a few seconds. Then tighten the chain back up and test it.

Craig

:grrr: hh:

 

[ourhouse]

If the chain jumped off the bar that usually puts some burrs on the drivers. I have an easy way to fix that, instead of filing both sides of each driver. Loosen the chain so it hangs off the bottom of the bar, not too much but make sure it is loose. Then start the saw and run it wide open for a few seconds. Then tighten the chain back up and test it.

Craig

If the chain is not that beat up I do the same thing. If it's realy burred up I use a raker file to fix the drive links.

 

[blthomas]

If the chain jumped off the bar that usually puts some burrs on the drivers. I have an easy way to fix that, instead of filing both sides of each driver. Loosen the chain so it hangs off the bottom of the bar, not too much but make sure it is loose. Then start the saw and run it wide open for a few seconds. Then tighten the chain back up and test it.

Craig

Interesting approach.

how loose is too much?

I'll have to give it a shot.

I ended up sitting in traffic all evening and only got the mule unloaded and some brought up to the house.

Thanks for the tips, I'll check them as soon as I can.

Blair

 

[blthomas]

I did as suggested, and it did remove the burs somewhat.

I haven't tried cutting anything though.

I had to drop a couple fence posts, so just for kicks I swapped chains, (I have a couple decent backups), and it actual fit just a touch better on the end of the bar. I'm going to run by my dealer and have a look see at what is on file for my info.

When dropping the fence posts, I had it wide open sideways and she didn't bind up at all.

The newest chain sits ever so slightly off the tip of the bar, maybe a 64th. The old chain that I used to cut fence posts today sits smooth all the way around. Almost like the runners are a touch to close on the newest chain and it rides higher some.

Sorry for lack of correct terminology, I'm gonna call the folks tomorrow.


Cheers,
Blair