Stihl MS291 Bar and Chain Getting Too Hot

[amc019]

Hello all,

I am new to the chainsaw ownership world, but after purchasing 50 acres of wooded and pasture land that needs a lot of cleaning up, I bought my first saw. I had handled other saws of family members before, but didn't know much about them. Just the proper way to use them in order to keep from hurting myself pretty much. Anyway, after doing some research on this forum and others, I purchased a the Stihl MS 291 with an 18" bar and .325 RM3 chain (whatever that means). I also bought the chain sharpening kit at the same time because it seemed pretty much fool proof.

Anyway, after cutting up a few 24-30" oak trees that had fallen during a storm and only needing to sharpen the chain once, I decided to start clearing smaller cedar trees on the property so I could get the bush hog around easier. I cut the first about 10" above the ground, then planned to come back and cut the stump level with the ground. The bottom of the tree was probably only 8-10" in diameter, but the stump ball was quite a bit larger. Soon, the saw became very hot and was spitting smoke and burning the paint off the bar, but I did notice the chain remained oiled. I tried to re sharpen the chain again (hit a rock or two on a few smaller cedars I had cut before) and tightened it up, but the same problem still remains.

I read that sometimes this is caused by over tightening the chain, but it seems that the chain is where it is supposed to be when I pull the slack off the bottom, its got probably 1/4-1/2 of space between itself and the bar, but then it kind of snaps back up against the bar when I let go. I have been tightening it according to the manual, I think.

Any other advice? Should I just buy a new chain or is the bar at fault? The chain spins freely like it is supposed to when I spin it by hand, so I cant seem to figure what the problem is. I have more work to do tomorrow, so hopefully I can remedy this problem fairly easily. I also read where it may be that the chain is too dull, but I had just sharpened it before I got to this tree today, and my previous sharpening attempt seemed to work flawlessly.

I appreciate any advice yall may be willing to give. Thanks.

 

[wombler]

I had a very similar problem early on, after I sharpened my first chain in a cheapo grinder that had a bit too much "slack" in the system. What I ended up doing was that despite using the same angle on both sides, the looseness in the adjustment system meant that I ground back the cutters on one side more than the other, which caused the saw to want to cut in a curve. That also forced the chain's drive links (the bits that run in the groove in the bar) up against one side of the bar, increasing friction and generating heat, which made smoke (from the oil getting waaaaaay too hot), and also catching metal things on other metal things, causing sparks and general consternation.

The immediate solution to my problem was to buy another loop of chain, which cut like a dream and made it very clear that the problem was chain related, and after a bit more research about cutting in a curve, I figured out what I'd done with the grinder. Re-ground the cutters so they were even on both sides, and that chain went back into service and remained acceptable thereafter (at least until the cheapo big box store saw I had **** itself, and I caught a bad case of hardcore Chainsaw Acquisition Syndrome; now all my saws run 3/8" chain). I also tend to hand file most of the time, and have a crazy device similar to a granberg file-n-joint to bring my chains back to near-new every now and then.

Another thing that can cause sparks is when the chain hits small rocks and other bits of random crap; if you're cutting close to ground level, the bark and even the wood itself will be full of that stuff, kicked up from rain and such. Cutting that sort of thing also dulls a chain *really* quickly, and you'll spend more time sharpening than cutting in order to keep an acceptable degree of sharpness on the chain.

As for your chain tightness, is that 1/4" to 1/2" of space measured from the bottom of the drive links, or from the tie links (the bit that you can see when the chain is sitting on the bar)? If the latter, that's *way* too tight; you should be able to see clear space between the bottom of the drive links and the bar. My tightening procedure these days is to hold the bar tip up in the air, then tighten until the chain *just* gets pulled flat against the bar and there's no visible "sag" in the chain, but no more. I then spin the chain a couple of times by hand to make sure it's fully on the sprocket and bar. It usually isn't, meaning it'll then go slack again, and I tighten it up some more. On a new chain (one that isn't pre-stretched, anyway), it'll probably stretch a bit after a tank of fuel, so I keep a scrench in my toolbelt to retension the chain regularly. The thing about chains is that they don't jump off because they're a "bit" loose (they've got to be sagging badly before they'll leap off just for the heck of it), something's got to push them off, like clearing brush or something.

 

[amc019]

Thanks for the quick reply.

I was measuring 1/4-1/2" of free space between the bar and the chain, so from the very top of the chain to the very bottom of the bar. Might need to re-check my owners manual to double check. I think I have been over tightening the chain for sure.

I guess what I will start with that tomorrow and go through taking my time and resharpen the chain, because I did it fairly quickly today and take not on how to properly adjust the chain tension. Should I adjust the tension any differently when its hot versus when its cooled down?

When you say hold the saw tip in the air, do you mean straight up and down vertically?

 

[Khntr85]

I agree with how he tightens his chain, hold bar up and slowly tighten chain til it barely touches the bottom of the bar.... I personally would say you had chain to tight, and probably was pinching the bar some when stumping the tree.... Also when stumping you will get a lot of mud, rocks in the bark.....if you can keep a separate chain just for stumping, preferably a chain that is at the end of its life....

If you bought 2-chains at once which is usually how dealers sell them, look at the new chain very closely, and sharpen the chain you have been using the same way..... Also dont forget to flip your bar over each time you sharpen the chain!!!!

Oh and not saying this to be a **** by any means, but have you turned the adjustable oiler all the way up???

Please report back and let us know how you are doing!!!!!!!

 

[AVB]

Stump cutting is one of the hardest thing in my opinion for chainsaw to do. You got re-sharpen the chain or chains quite often. If when cutting it isn't cutting like a hot knife thru butter then it is probably dull. Stumps close to the ground contains small rocks, dirt, and even pieces of other foreign materials. When cutting stumps I may not get through one before I got to stop and sharpen my chain and re-tensioning or at least I did this spring and I was only cutting small soft wood brush stumps. I don't normally cut close so close to the ground as you say I too was wanting to get in with my mower or bush hog later but the poison ivy is keeping me at bay right now and I won't get finish until winter again.

Try cleaning the bar groove, checking the drag links for burrs, and resharpen for chain(s).

 

[Ozhoo]

...have you turned the adjustable oiler all the way up???

Unlike their predecessors, MS291's don't have an adjustable oil.

 

[Khntr85]

Wow that's to bad.... Thanks for letting me know.... My ms290 oils a 20" bar really good!!!!
Now I am curious how the ms291s oil since they have a fixed oiler...

 

[amc019]

I agree with how he tightens his chain, hold bar up and slowly tighten chain til it barely touches the bottom of the bar.... I personally would say you had chain to tight, and probably was pinching the bar some when stumping the tree.... Also when stumping you will get a lot of mud, rocks in the bark.....if you can keep a separate chain just for stumping, preferably a chain that is at the end of its life....

If you bought 2-chains at once which is usually how dealers sell them, look at the new chain very closely, and sharpen the chain you have been using the same way..... Also dont forget to flip your bar over each time you sharpen the chain!!!!

Oh and not saying this to be a **** by any means, but have you turned the adjustable oiler all the way up???

Please report back and let us know how you are doing!!!!!!!

I was unaware that this model had an adjustable oiler, but I will look in the manual to see. I might as well just buy another chain I guess and see if I can match the cut on it to the old unit with the sharpener.

Also, what are the benefits to flipping the bar over each time I sharpen the chain?

 

[amc019]

Stump cutting is one of the hardest thing in my opinion for chainsaw to do. You got re-sharpen the chain or chains quite often. If when cutting it isn't cutting like a hot knife thru butter then it is probably dull. Stumps close to the ground contains small rocks, dirt, and even pieces of other foreign materials. When cutting stumps I may not get through one before I got to stop and sharpen my chain and re-tensioning or at least I did this spring and I was only cutting small soft wood brush stumps. I don't normally cut close so close to the ground as you say I too was wanting to get in with my mower or bush hog later but the poison ivy is keeping me at bay right now and I won't get finish until winter again.

Try cleaning the bar groove, checking the drag links for burrs, and resharpen for chain(s).

Funny you mention the poison ivy, it gets me almost every time I get the saw out to cut limbs or even mow up close to the trees on the tractor, and I can never spot it before its too late.

I'll try all of the above this afternoon and see how it turns out.

 

[KenJax Tree]

It doesn't sound like a tension problem. Post some pics of the chips, i bet the chain isn't as sharp as you think it is.

 

[amc019]

It doesn't sound like a tension problem. Post some pics of the chips, i bet the chain isn't as sharp as you think it is.

Chips as in the wood chips coming out as I cut?

 

[KenJax Tree]

The ones laying on the ground after you make a cut

 

[Khntr85]

I was unaware that this model had an adjustable oiler, but I will look in the manual to see. I might as well just buy another chain I guess and see if I can match the cut on it to the old unit with the sharpener.

Also, what are the benefits to flipping the bar over each time I sharpen the chain?

I was wrong about your ms291 having an adjustable oiler.... My ms290 which is the prior model does have a adjustable oiler.....

Flipping the bar will make it wear on both sides evenly.... If you don't flip it you will only get half the life out of it....

Also you won't need to do it right now, but you will need to learn how to "dress" a bar too.... Type in "dressing bar" in the search here and study up when you have some time....

I know it seems like a lot of maintenance, but with practice, you will get used to doing it all regularly and it will be 2nd nature to ya....just don't worry about perfecting it all at once, no one has done it yet lol.... Practice, practice, practice....my woman thinks I am nuts because I am always sharpening, dressing a bar, or working on a chainsaw.... They last a lot longer when properly maintained!!!!!

(EDIT)---you can flip the bar every other sharpening, I just do it every time I sharpen out of habit...

 

[Ozhoo]

I was wrong about your ms291 having an adjustable oiler.... My ms290 which is the prior model does have a adjustable oiler.....

291's fixed oiler flows the same volume as a 290's adjustable oily on the minimum setting. I forget the actual number but it's pretty stingy.

 

[Khntr85]

291's fixed oiler flows the same volume as a 290's adjustable oily on the minimum setting. I forget the actual number but it's pretty stingy.

Oh my that is down right pathetic, that may not be the OPs problem but it ain't helping.... At what point do they say ya we have to meet epa standard, but people can't cut 10+ inch stuff without burning threw it.... Absolutely ridiculous!!!!

Like I said my older 290 is a straight gusher almost too much when turned all the way up!!!!

 

[amc019]

It was the chain, it wasn't nearly as sharp as I thought it was, and it was in pretty bad shape after I looked at brand new chain in the store. Lesson learned there. I sharpened it up for a back up and bought a replacement. Thanks fellas.

 

[Okie]

It was the chain, it wasn't nearly as sharp as I thought it was, and it was in pretty bad shape after I looked at brand new chain in the store. Lesson learned there. I sharpened it up for a back up and bought a replacement. Thanks fellas.

I did not read all of this thread but did notice you found your issues as being a chain that you sharpened wrong.

Cutting stumps next to the ground is going to ruin chains fast.

You need to do some research as to how to hand sharpen a chain, the chain you have screwed up for instance and you can cut down the depth tangs of the old dull chain and once you get the hang of hand filing in the field you are good to go.

Remain calm, you are getting experience on cutting stumps and ruining chains.

For stumps I sue my old disposable type chains and chainsaws instead of my good wood cutting saws with good new chains.

I don't use low kickback chains either. They do not cut as aggressive even when new.

Sure depressing when you see sparks off of a new chain and some trees will actually have a rock up inside growed into the tree.
Rock hard blackjack trees are another type that will dull a chain fast, you can see sparks coming off their dead hard limbs at night.

 

[Khntr85]

It was the chain, it wasn't nearly as sharp as I thought it was, and it was in pretty bad shape after I looked at brand new chain in the store. Lesson learned there. I sharpened it up for a back up and bought a replacement. Thanks fellas.

Hey man that's actually just fine, one of the cheapest lessons learned with a saw lol....as every one has stated there is all kinds of stuff hiding at the base of a tree....... Now it would be best if you could keep a spare "brand new" chain, or if they would give a single cutter link at your dealer....that way you can always reference back and see if you are sharpening it correctly.....

Glad to hear everything is good, keep us posted!!!!!