Yes another chain/saw question

[sb47]

I have been using the same chain and bar setup for many years. Same bar, same chain. But the last year or so I have been running into a new problem. When I put on a brand new chain and I adjust it I end up with half the chain adjustment already half way used up. Here is a few pics.

This is my ms362 with a brand new chain and as you can see it's already half way along it's adjustment. Im running a 20 bar with a 36RM-72 chain#3652-005-0072 and is what all the sthil dealers recommend.



Here is my MS 261 with the same issue. I also run a 20'' bar with a 26RM - 81 Part # 3686-005-0081. On this one you can see there is less then half an inch of adjustment before I run out of adjustment. It also has a fairly new bar so not a lot of bar wear ether.



By the time it stretches past the limit of the adjustment I still have over half the teeth left. I keep my chains very sharp and never run them when they get dull. I am cutting green oak and I can usually get 5 or 6 tanks of gas run before I have to touch them up unless I hit something. This is with a new sprocket so sprocket wear shouldn't be the issue. I am also cutting mostly large rounds of at least 12'' to 48'' so I'm in big wood most of the time. Is this normal? I don't remember having this issue a few years ago. Am I using the wrong size chain? What's going on here. Thanks

 

[J D]

If there has been a sudden noticable change in where the bar sits check the bar tip to make sure the sprocket bearing hasn't collapsed. After that check the markings on the bar for the DL count & count the chain, "same length" bars can vary by a few links.
It's not that uncommon for the bar to sit in the middle of it's adjustment. If you're regularly buried in hard wood you may find your getting excessive chain stretch, especially if your chain isn't proper sharp or bar oil is on the light side.

 

[sb47]

If there has been a sudden noticable change in where the bar sits check the bar tip to make sure the sprocket bearing hasn't collapsed. After that check the markings on the bar for the DL count & count the chain, "same length" bars can vary by a few links.
It's not that uncommon for the bar to sit in the middle of it's adjustment. If you're regularly buried in hard wood you may find your getting excessive chain stretch, especially if your chain isn't proper sharp or bar oil is on the light side.

Thanks I'll check the front sprocket but it spins freely when I use high pressure air when I clean out the slot on the bar. In fact it spins so fast it sounds like a serine. I replaced the bar on the 261 not long ago and it matched up exactly to the old one. I put a new drive sprocket new bar and new chain with the same results. In the past the adjustment would last until I had no teeth left on the chain. Now I'm running out of adjustment long before I wear down the teeth. Something has changed.

 

[J D]

Oil?

 

[farmer steve]

I'm reading this as these are stihl brand chains. ???

 

[Dennisthemenace]

Seems like a lot of stretch

 

[HumBurner]

I'm not familiar with those two saws, so this is a shot in the dark.

Does the tensioner have a clip or holder of some kind on one or both ends of its channel?

It's possible you've worn them out allowing the tensioner to move.

I had one that would "jump" at least a quarter inch when tightening (can see it happen with no chain on), as well when loosening. Eats up slack the tensioner might need.

 

[Overlooker]

Figuring out the cause of the problem certainly seems warranted, but can you shorten the chains minimally to let you use them until the teeth are worn out? I can shorten a chain in my shop with no special tools for the cost of a repair link. O

 

[sand sock]

My stihl dealer was bought out\forced out and i no longer have allegance to them. So i have been experimenting with what ever chain is available. 20 inch 3/8 .050 72 drivers. Between stihl and husky chains. I have noticed the tensioner sits in 2 different spots , depending on the chain brand. I think it has to do with the side plate , either the heigth or rivot placement heigth. I hand sharpen alot and am getting back to the unsafe hash marks and have never seen a chain stretch yet. I touch up chains every tank or 2 of gas.

 

[djg james]

Figuring out the cause of the problem certainly seems warranted, but can you shorten the chains minimally to let you use them until the teeth are worn out? I can shorten a chain in my shop with no special tools for the cost of a repair link. O

I'd like to learn how to do this since I have several chains with a similar problem. Source of 'repair link'? Photos of process?

 

[Abbeville TSI]

Never ever use air to spin a bearing dry unless you hold the parts so they won't spin. You can cause the bearing to come apart or damage it so it comes apart later. That goes for all bearings, period.
The bar tip bearings get enough lube through normal use.

 

[lone wolf]

@Franny K

 

[sb47]

All good points so far. I have been looking for a kit to take a link out of the chain but I have not found anything as of yet. I'd prefer using a chain breaker to take one apart vs grinding a rivet and using a drift pin to to take it apart. Even then I still need the right parts to put it back together.
I always dip the tip in oil after cleaning with air and I only spin it for a second just to make sure I get any dirt or debris out. Never had a tip bearing go out. Yes they are sthil chains from a sthil dealer.
I have not noticed the adjuster skip but I will check that.

 

[HarleyT]

Take off the bar/chain and put up some better pics of the sprocket's teeth.

 

[sb47]

I feel like i'm not getting my moneys worth if I run out of adjustment before I wear out the teeth.

 

[3000 FPS]

I have run in to this before from switching different bars around on different saws.
I usually just take one link out of the chain when it gets a little stretched out. No biggie.

 

[Franny K]

Stihl chains are supposedly stretched in the assembly process. At least in the picco 3/8 a loop is a bit longer than an Oregon one out of the box. Perhaps the tension settings in the machinery changed.

 

[farmer steve]

I feel like i'm not getting my moneys worth if I run out of adjustment before I wear out the teeth.

So all I run are stihl chains and never had any stretch before I wore them out. Compare a used one to a new one to check length. I know you cut a lot of wood but how tight do you tension them?

 

[farmer steve]

Any pics of the numbers on your 362 bar #'sb? Just talked to my stihl guy and asked him if he has had anyone with chain stretching problems in the last year and he said no.

 

[sb47]

So all I run are stihl chains and never had any stretch before I wore them out. Compare a used one to a new one to check length. I know you cut a lot of wood but how tight do you tension them?

I don't over tighten the chain. Thats not the issue. The adjustment is half way with a brand new chain that has no stretch at all. I take out the slack till the chain is just touching the bottom of the bar but not really tight at all.