seized a sprocket tip

[JONSSTIHL]

this weekend I seized the sprocket tip on my brand new stihl bar (it still has the paint on it) only about 3 face cords cut with it.

I was cutting a stump off with the saw on it's side and suddenly the chain just stopped.

when I got it home and took it apart I got the tip sprocket to turn with a hammer and a screwdriver and I finally got it to turn freely. turns out it was jammed with wood chips.

this was with stihl RS chain. has this ever happened to anyone else

thanks

 

[SawTroll]

I has happened to me a couple of times - and I have fixed it in about the same way, but at the cutting site.

If the rails has been pinched slightly together, it may help to cautiously pry them apart with a suitable screwdriver - at least it worked for me last saturday.....:greenchainsaw:

 

[Bermie]

Its happened to me several times.
I think it was the RM2 chain I was using, for some reason my 020 does not like to cut larger bits of really hard wood with this chain, the rail gets clogged and the sprocket jams up. I've had to take it apart and free it while up in the tree more than once!
I jammed the nose sprocket but good the other day on a 250 doing bore cuts while felling with RM2 chain, wrecked the bar, spread the rails at the tip. I have since changed to RM chain. The bar is now a training aid!

I have several old dental picks in my toolkit which work really well to dig out the chips around the sprocket.

 

[WRW]

Making long, deep, horizontal cuts tends to do just this. Any time the chips can't be cleared efficiently the operator can pull out of the cut and goose the saw a couple of times to clear chips from the bar, chain, and clutch cover and then goose it a couple of times as you re-enter the cut to get the chips out of the cut.

Usually I can clear this condition (the seizing) by dragging the chain back and forth across some available wood or bark without disassembling the saw. It may take some pressure.

 

[JONSSTIHL]

thanks for all the tips. atleast I know I'm not alone. it was the first time it happened to me. but it was jammed tight there was no way rubbing it on a log was going to get it loose but I'll keep that in mind if I catch it before it binds completely next time.

thanks

 

[B_Turner]

Seems to happen more when bar is getting hot from a chain not quite sharp.

 

[jack-the-ripper]

I had the same thing happen with the brand new 28" bar on my MS660 this year. It will be the last Stihl bar I buy. Did you have to tighten your chain often?

 

[daemon2525]

Yes, It happens, I, Like the rest, drag it hard on the log to get it to turn.

 

[RaisedByWolves]

I had this happen with my 925 while cutting some dried red oak and thought it was just a fluke.


The shain had about 1/4-3/8" of chips about 2" long binding the chain right behind the sprocket. Stopped that saw dead, thats not easy to do.



Had to pry/beat the chips out with a screwdriver they were packed so tight, damn near like a solid piece of wood.

 

[Freakingstang]

I had the same thing happen with the brand new 28" bar on my MS660 this year. It will be the last Stihl bar I buy. Did you have to tighten your chain often?

I only run Stihl bars. they last longer and have some of the best tips out there.


From your comment about tightening the chain, that was most likely your problem. Yes, on a new chain, you have to tighten it quite a bit as it streches. A loose chain will let more chips in the rail and lead to sprocket seizing. Also a dull chain as mentioned will do it in short order, as will making curly fries. Longer chains stretch more than short ones, so it will seem like you have to adjust them more...set them with No sag but yet No Drag....

 

[Justsaws]

Stump it with a hard tip.

 

[jack-the-ripper]

As I stated in an earlier post, I removed the Stihl B & C and replaced it with a Windsor speed tip. No more troubles. To each his own.

 

[yawning_dog]

lye

Hi Jonsstihl-

I just had the same thing happen to me. I was cutting a bunch of eucalyptus rounds into smaller more manageable pieces. I was mostly quartering them so I was going with the grain and creating long stringy "chips". Anyway, the chain just stopped. Even after rubbing it back and forth on a piece, no dice. I thought it was toast, but I had the idea to soak the tip in a lye solution. I just took one of those big-gulp type cups, mixed up some lye/water in it, and let the bar tip soak for a couple hours. I took it out occasionally to move the sprocket tip around. Worked like a champ!

 

[GASoline71]

I only run Stihl bars. they last longer and have some of the best tips out there.

Ditto.

Gary

 

[yawning_dog]

lye on blacktop

Oh, by the way, in case you try the lye thing, don't dump it out on blacktop in front of your house... I was trying to save my pipes and a few fish so rather than dump out my cup-o-lye down the drain or in the storm drain I just chucked it in the middle of the street in the court where we live. It was probably only about 12 oz or so and I figured it would just evaporate. Well did and left a nice big white patch where the offending liquid was. Like as in nice white latex paint. Shhhhhh don't tell the neighbors....

 

[SmokinDodge]

I only run Stihl bars. they last longer and have some of the best tips out there.


From your comment about tightening the chain, that was most likely your problem. Yes, on a new chain, you have to tighten it quite a bit as it streches. A loose chain will let more chips in the rail and lead to sprocket seizing. Also a dull chain as mentioned will do it in short order, as will making curly fries. Longer chains stretch more than short ones, so it will seem like you have to adjust them more...set them with No sag but yet No Drag....

Steve I noticed your comment about adjusting the chain and having to do it more often with new chain. I've thought a lot about this and recently I soaked a brand new 20" RM chain in 30 wt oil overnight before using it. I put four tanks throught the 036 without having to adjust that chain once. When I did sharpen and adjust the chain it was a minimal amount to bring it up to par, something like 1/8th turn of the screw. I ended up putting eight tanks on that chain with only the one adjustment.