Chain saw adjustment

[UP Oliver]

Hello.

I have a Stihl 029 super chainsaw. I've had it for 22 years but have not gone through more than three or four gallons of bar and chain oil.

I cannot get the chain to tighten around the bar. I have not replaced any parts on the saw. The drive gear has grooves in it, but I can't believe they're deep enough to cause this much trouble. I have three chains and I can't get any of them to work. Is it possible that my bar is worn that much? Or a combination of that and the drive gear? The mechanism to tighten the chain bottoms out before the chain is tightened.

Any help is appreciated.

 

[Mule Meat]

Chains are worn out.
Clutch drum worn. If it has grooves cut in the center of the teeth. It is time to replace it.

Most likely your bar has a nose sprocket to keep the nose of the bar from wearing and to reduce friction. If so. Wouldn't think the bar is worn enough to cause the chain to be to long.

If mine.. I would replace all three. The bar, chain and sprocket at the same time. Then check about adjusting the oil pump to a higher flow rate.

 

[MarkB_MI]

There are a couple of different size sprockets for the 029. I replaced the original one on my saw with one that had more teeth. I think the original had 7 teeth and the replacement had 8. I seem to recall the chain was a bit tighter with the replacement sprocket.

I assume the adjuster itself is moving the bar when you turn the adjustment screw, and that the pin on the adjuster engages the hole in the bar.

 

[GordyMN]

I have an 026 and a 036, so I think they are somewhat similar. I had the same problem, but after I blew out the affected areas with my air compressor, it was much easier to see and work on. my problem was starting the peg (that adjusts the chain) in the right place. once it was started correctly, it all went together. i also have a 009L - that is old, but it it my favorite saw. GordyMN

 

[UP Oliver]

Thank you for the input.

I have been using the same chain for a while, probably several years. Last time I used the other chains they were fine. The pin is in the hole and does move the bar forward when I turn the screw. But the screw is tight before the chain is adjusted properly. And the metal piece that the pin is on pushes right up against that plastic piece in the front of that groove.

I do have a sprocket in the front of my bar, and I do the same thing with the compressor. I'm thinking a combination of the drive sprocket and the bar is my problem.

 

[rustred]

you need to make sure you are replacing the chain with the exact one that it had before. lots of different pitch chains. and thats exactly what they will do. a little wear on the sprocket dont affect the chain fitting correctly. and if the adjuster bottoms out first the chain is really worn and is junk.

 

[Zachary Hoyt]

I would take the bar off and look at the moving parts in the tension adjuster. It's possible for dust to build up in the hole and keep the pin from traveling all the way out. Also it's possible to have stripped threads on the screw that make it resist turning and feel like you've gotten to the end of the travel. I have never seen or heard of a seriously stretched saw chain, the teeth get filed off but the chain part doesn't stretch that much in my experience. I've never gotten close to the end of the adjustment on any of the Stihls I've had, usually the chain stretches a little in the first hour of use and then only very slightly after that.

 

[Russ from MN]

It sounds like the chains are wore out! Bars and drive sprockets should not wear out that quickly. Chains can be shortened, but if it's worn that bad it's probably not worth it. I have never had a chain wear to the point where it wouldn't tighten, so I would look everything over very carefully to make sure you're not missing something, it doesn't sound right. My chains are always sharpened away on top long before they stretch that much.

 

[Russ from MN]

Like Gordy said, use compressed air to blow the whole area clean, especially the cavity where the tightener screw is, there might be enough sawdust to stop the tightener from going full travel. Let us know what you find!

 

[Stephen Newell]

A chain can stretch to the point where a link needs to be removed to allow it to fit. I throw the chain away when it gets to that point though. I figure by then the drive link is worn to a point where it does more damage to the bar than the chain is worth. Since I started doing that my bars are lasting much longer than the days I used to have links removed. If your chain bar is a solid bar, meaning it doesn't have a wheel on the end then it could be very well worn out in 22 years. I've had them spread apart where it kind of pinched the chain. Usually when I have a bar that goes bad it starts cutting through a log on a curve instead of straight through.

As far as oil consumption, my stihl saw uses almost a tank of oil with every tank of gas. I always add oil every time I add gas. Cutting firewood I use more than five quarts of oil every season.

 

[3000OH]

Youve gotten good advice here. We have an 029 with hours on it. If youve never replaced the drive sprocket, youre due for one. Somewhere I read a very good article that laid out how sprocket wear (both drive & bar) combine to make the chain not fit correctly (almost imperceptibly) and that leads to even faster wear of chain & sprockets. You were also given good caution about making sure that chain & bar & sprocket match. A mismatch may look ok but it isnt.

FWIW, Ive gotten lots of good chain, bar, and sprocket parts and info from Baileys. They have so much stuff that you have to be very careful to make sure that youre ordering all compatible parts. Good company, in my experience.
Baileys

 

[Blackhole49]

I have a 37 year old Shindiawa 500 saw. When I was heating with wood, I cut 10 to 12 full cord of wood a year. The saw is on its second bar and I have used countless gallons of 20w50 motor oil for bar lube. I've sharpened all my chains to what you see in the pic. before discarding. In all these years, I have never run out of adjustment in the bar. Are you sure something else isn't going on?

 

[UP Oliver]

Thank you for all the comments and information. I appreciate it. It is impossible for my bar to go any further forward, the back of the hole in the bar that the bolts goes through is right up against the back of the back bolt. So my tensioner must be fine. I thoroughly clean everything often.

The last time I used the other chains they were fine. I will be looking into getting a new bar and sprocket. Or maybe a new saw? Seems like everybody where I live has at least a few except me.

Thanks again.

 

[UP Oliver]

Thank you for the information. That sheds some light on the situation for sure. I'm going to take a closer look at it today, but when the bar is all the way up against the back bolt I don't know how it can go forward anymore.

Thanks again.

 

[Dave BN]

Well if the elongated holes in the bar are hitting up against the mounting bolts then you have all the adjustment you can get. But look it over closely again. Those adjustments always confuse me and seem backward until I look long enough to get my head wrapped around it.
A couple of thoughts.
I have NEVER run out of adjustment because of a worn chain, sprocket or bar. I seem to remember putting the adjuster dog in the oil hole instead of the adjuster hole and then couldn't get the chain tight one time. Or maybe you had the wrong chain to start with. Different tooth count on the drive sprocket, as someone mentioned earlier, makes the chain run faster thus a faster cut if you engine has enough power. I guess I would buy a new chain of the correct size and see what happens. Lots of size options so look carefully and maybe go to a saw shop not a big box stores or internet. I have saws that I modified and so they take a different chain than the book says.
Dave.

 

[Bret4207]

In addition to the bar nose being worn, the chain being stretched and the sprocket being worn out, you also need to check the clutch bearing(s). With the chain off just grab the clutch and see if it's tight on the shaft or if there's much play. Shouldn't be much play at all. There is either one or two needle roller bearings in there that don't get much lube and sawdust can build up and help them over heat and go bad. Not a hard job to change, nor expensive.

 

[Steve@Advance]

I think all you need is the correct length chain.

I've never had one wear so far that it ran out of adjustment.

A worn sprocket will not have enough effect to cause that. The roller in the end of the bar will not wear to the point of causing that (unless it is completely trashed and that would be very obvious and smoking blue hot).

 

[grizz02]

Are you over tightening the chain , with the saw sitting on the bench the bar should hang free then slowly tighten the chain till there is some slack when you pull down on the chain , then tighten the nuts, the chain will tighten up even more , is your oiler working ?

 

[rvirgil_KS]

Are you lifting the tip of the bar when you adjust and tighten it? Sounds like you could have a combination of problems.

 

[UP Oliver]

Thank you again for all the responses.

I do everything correctly when I tighten my chain, same way I've done it for many years without problems.

Not sure everybody noticed, but I do have two other chains that worked perfectly fine in the past and I cannot get either one of them to tighten properly now either, so I do not think it's my chain. I don't use as much bar oil as some people have stated here, so that is interesting. I will look thoroughly today, but I don't know what else I can do if the bar is as far forward as it can go and will not tighten any of the chains.

Thanks.

 

[MarkB_MI]

I took a look at my 029 today and was surprised to find it has the original 7-tooth sprocket on it, not the replacement 8-tooth. I must have not been satisfied with how the 8-tooth worked on the oak I usually cut and changed it back. (I really need to buy a new 7-tooth sprocket, because it's REALLY worn out now.) The 8 tooth sprocket is noticeably larger, so if you put one on your saw you should be able to use your current bar and chains. If you only cut softwood, the 8 tooth will probably work fine.

 

[UP Oliver]

Thanks again for all the input. As I mentioned, I went out and looked at it again today real close. I'm not sure how much of a difference a new sprocket is going to make, but I'm convinced that's what I need. When I have it tightened as much as I can, I put a screwdriver in between the sprocket and the chain and gave it a slight turn and it snugs the chain up. My sprocket is worn pretty good in my opinion.

I wish I had a new saw so I could see where the tightening mechanism is when a blade is adjusted properly. Seems like there's a lot of travel in mine and I can't believe I have worn down the sprocket and chains and bar that much such that I am out of adjustment room.

Thanks.

 

[Stephen Newell]

You wouldn't have to have a new saw, take it by a lawn mower repair shop and have them evaluate it and adjust the chain for you.

 

[MKinON]

The last time you used the bar and chains ... Did you have the chains sharpened at a shop between uses and get someone else's back instead. I would check to see if those chains are all the same. I doubt the chain stretched that much. You say you've put a few gallons of bar oil through the saw. In it's life? Definitely not enough to stretch any of those chains that much or wear anything out.

 

[UP Oliver]

Thank you for your input.

I have not had my change sharpened at a shop in many years. They have all worked fine since the last time.

Yes, only a few gallons of bar and chain oil in the lifetime of the saw. I could be wrong, maybe it's been five or six gallons. I just don't cut that much firewood. I think the key is that I cannot tension it properly with any of my chains.

Thanks.

 

[guido]

Up Oliver,

Usually is the chain that is stretched. Its possible, but have never seen a sprocket that wore out.
If you are handy with a drill, just make a hole in the bar to get more adjustment. if all your chains are THAT stretched, you should take a close look at you chain oil rate. Also make sure that the bar oil holes are clean. They usually get gummed up, and stops oil from lubing the chain. That in turn stretches the links, if that continues, you wind up with no adjustment left,


Guido.

 

[Bret4207]

One other possibility is that the chain was too long to start with. Some bar and chain combinations take a slightly longer or shorter chain. We used to stock 3/8 chisel in 70,72 and 73 driver links and all fit different 20" bar's, but all were for a "Husky with a 20" bar".

 

[Destroked 450]

I worked for a losing outfit many years ago using Husqvarna Saws,
They were adjusted to use 2 tanks of gas per 1 tank of oil.
It's odd that chains that used to work don't now, how much slack does the chain have when adjusted all of the way back.

Can you post a photo of the saw adjusted out with the side cover off

 

[Dusty MI]

Maybe the adjusting screw/nut is stripped.

Dusty

 

[BarnyardEngineering]

(quoted from post at 07:32:29 08/01/21) Thank you for your input.

I have not had my change sharpened at a shop in many years. They have all worked fine since the last time.

Yes, only a few gallons of bar and chain oil in the lifetime of the saw. I could be wrong, maybe it's been five or six gallons. I just don't cut that much firewood. I think the key is that I cannot tension it properly with any of my chains.

Thanks.

The more this goes on, the more I'm convinced that something unusual is going on here.

Chains, sprockets, bars, do NOT wear that much. Not based on how much you say you've used the saw.

Three chains do NOT all wear out at the same time. They don't spontaneously grow extra links and become the wrong chain.

Either it's just a mistake, a brain fart, or something is broken on the saw itself. Any chance that a kid/grandkid was secretly playing with the saw, and dropped it?

Just to be sure here, the REAR bolt is touching the REAR of the slot in the bar? If it's the front bolt and the front of the slot, that's all the way loose. Stranger things have happened. You just get it in your head that things should be a certain way, and become blind to the problem you're causing yourself.