stihl 201 kickback when starting

[BlackBikeDave]

I have a brand new (1 year old) stihl 201 TCM.
I'm not a daily climber so this saw has not seen a heavy amount of work yet. Its been broken in and has been used with no problems except for one.
While on a job I was in the tree and held my saw firmly as I went to pull the cord. The pull cord seemed to lock causing the entire saw to pull with my pulling hand. It didn't turn over just pulled the whole saw. The saw had been warmed up while on the ground 1st and I had made a few cuts already. That's why I'm not sure why this is happening.
Anyone know why?
I've been running saws for years and never had this happen.
thanks




If this is on the forum already I'm sorry. I couldn't find an answer.

 

[SeanKroll]

Have your removed your starter cover? That's were I'd start.
I haven't heard of this issue.

Welcome to the TreeHouse @BlackBikeDave !
Great folks here!

the "What's New", then "New Posts" is a great way to navigate the forum for new posts since you last looked.
"@" before a username gives that person an Inbox notification that they are being referenced in a post.

 

[Burnham]

Hopefully the fuel/oil mix was proper. Otherwise, it might be seized if accidentally straight gas was used given your report on the sequence of events.

Welcome, sir.

 

[Mick!]

Something jammed in the starter cord mechanism.
Undo 4 screws and have a look.

 

[Bart]

When you have the pull starter off you can check to see if the flywheel spins freely (excepting the compression bounce). Next I'd pop off the bar/chain/clutch to see if something jammed there. If you're left with a stuck crankshaft - bad juju

 

[Kaveman]

Welcome! And I agree with all the wonderful advise given above.

Saws that get run on straight gas sound harsh, you can hear their death cries. They sound like they're about to blow up.

Most likely it's the pull starter. More common than you might think. There's some moving parts in there that actually spend most of their time sitting still, while other stuff moves around them.

Typically if something is bound up on the bar/chain side of things, the clutch allows the saw to start, but it's like the brake is stuck on, just lots of bog.

 

[BlackSmith]

Had a 55 Husky give to me that would do that. The guy said it started doing that after he replaced the sprocket. I asked him how he took the old one off. He said a wrench and hammer. I knew then that the flywheel key was sheared. Took it off and sure enough. Damn key was molded into the flywheel not separate. New wheel was around $120 at the time. Cheap little saw and still runs great.

 

[Nutball]

Had a 55 Husky give to me that would do that. The guy said it started doing that after he replaced the sprocket. I asked him how he took the old one off. He said a wrench and hammer. I knew then that the flywheel key was sheared. Took it off and sure enough. Damn key was molded into the flywheel not separate. New wheel was around $120 at the time. Cheap little saw and still runs great.

If anything, I'd think a broken key would cause retarded timing, or a completely loose flywheel, because either the shaft will spin ahead of the flywheel and tighten it down, or loosen it, which should make it really loose. Strange things happen at high speed.

I've had 201t's be randomly hard to pull like the OP says. I never thought to check the key. I just figured it was some other flaw common to them.

 

[cory]

On the topic of flywheels and saws that die- I was cutting up a big tree on a hot summer day and in the middle of a full speed cut, the engine stopped dead, and cord wouldn't pull for restart, I figured I'd blown up the saw. Took it to dealer, told them what happened and asked them to determine cause and repairability, couple days later they called and saw was shot/not worth repairing. I picked up the saw from them for parts, and noticed it was still covered with sawdust, as if it hadn't been taken apart. I gave the saw to the Ninja cuz he will take any and all junk. Few weeks later he reported the saw was fully repaired and running perfect, and 5 years later he still uses it most every day. A bolt behind flywheel had backed out slightly and caught the flywheel, stopping it dead. He tightened bolt and all was good. .

So I gave away a 900$ saw because of a loose bolt. Dealer apparently figured saw was shot cuz cord wouldn't pull. Later, a knowledgable dealer told me that when saws die/burn up, they usually start running super shitty rather than seizing up.

At least the Ninja got a good saw.

 

[lxskllr]

My brushcutter just died when it overheated. Took it off the harness and see a huge wineberry leaf plastered over the air intake. I think "Oh... That's not good...". Give it a few pulls and nothing. Take the muffler off, and the piston's gouged to hell. It's in the garage as a parts saw. It might not require much, especially if the cylinder's still good, but I don't need it atm, so it sits.

 

[Kaveman]

Hey, good on the ninja for being a junk collector.

On a related note, I can't tell you how many perfectly good saws I've picked up second hand at yard sales, with the chains on backward and a hole in the fuel line!

Once I spotted "MAGN" peeking out from under some stuff in a lady's garage. I went home with a basically new 660, for $200. Hubby had bought it because it was the biggest baddest saw at Ace hardware. When he realized it was too much for him, the local pawn shop offered him $150. It sat for a year and then I spotted it under a welcome mat. It became my first ported saw...

 

[Treeaddict]

My brushcutter just died when it overheated. Took it off the harness and see a huge wineberry leaf plastered over the air intake. I think "Oh... That's not good...". Give it a few pulls and nothing. Take the muffler off, and the piston's gouged to hell. It's in the garage as a parts saw. It might not require much, especially if the cylinder's still good, but I don't need it atm, so it sits.

Your second/working brush cutter? Or, are you just retelling the story of how one died a year or so ago?

 

[lxskllr]

It's the one from a year or so ago. I still have the other identical Husky and the Stihl.

 

[BlackSmith]

I'd think a broken key would cause retarded timing,

The “key” was not an actual key. The flywheel was cast with a key where an actual key should have been used. Being aluminum it didn’t break clean like a key would but just kinda smeared. The flywheel was tight so my first thought was he used the hammer and wrench also to tighten the clutch, hell if I know. It acted like it was firing before tdc. It would run but it was hard on the fingers.

 

[Trains]

I have a brand new (1 year old) stihl 201 TCM.
I'm not a daily climber so this saw has not seen a heavy amount of work yet. Its been broken in and has been used with no problems except for one.
While on a job I was in the tree and held my saw firmly as I went to pull the cord. The pull cord seemed to lock causing the entire saw to pull with my pulling hand. It didn't turn over just pulled the whole saw. The saw had been warmed up while on the ground 1st and I had made a few cuts already. That's why I'm not sure why this is happening.
Anyone know why?
I've been running saws for years and never had this happen.
thanks




If this is on the forum already I'm sorry. I couldn't find an answer.

So after the saw locked, and moved back towards you.
were you able to start it normally afterwards, or send it back to the ground where they started it ?

or is it still locked up ?


sometimes saws can have moments where the cyld seems to have more compression and they are hard to pull over, or in this case, just dont spin and you end up with a bar and chain heading towards you or your lines.
if the needle is leaking, they can hydro lock as the fuel tank empties into the crankcase, but thats usually found upon first start in the mornings , but this is not whats happening here.

 

[Nutball]

It's possible that after idling long enough, and sitting flat, the 2 stroke oil can pool in the bottom of the transfer port, and get blown into the cylinder on the first pull. Hanging down should home to the cylinder up and prevent that.

 

[BlackBikeDave]

So after the saw locked, and moved back towards you.
were you able to start it normally afterwards, or send it back to the ground where they started it ?

or is it still locked up ?


sometimes saws can have moments where the cyld seems to have more compression and they are hard to pull over, or in this case, just dont spin and you end up with a bar and chain heading towards you or your lines.
if the needle is leaking, they can hydro lock as the fuel tank empties into the crankcase, but thats usually found upon first start in the mornings , but this is not whats happening here.

The saw would start and pull just fine after locking. After the pull that seemed like it was locked it pulled smooth and runs fine.
I took off the pull cord cover and noticed the way the cord recoils. It wraps in line with itself. Sometimes the outer wrap seems to "snap" over onto itself. Could the cord be too long? So that there are too many wraps and when the line rolls over on itself in the coil position it keeps the line from pulling out? Temporarily making the saw seem locked?
Everything seems fine and it just pulled and started with no problem except an expectation of it recurring randomly.
I'm no expert but it seems that the cord is suspect. It is very clean also.

 

[Burnham]

Perhaps the recoil spring needs another turn or two tighter...that higher tension might keep the cord in line better.

 

[Trains]

The saw would start and pull just fine after locking. After the pull that seemed like it was locked it pulled smooth and runs fine.
I took off the pull cord cover and noticed the way the cord recoils. It wraps in line with itself. Sometimes the outer wrap seems to "snap" over onto itself. Could the cord be too long? So that there are too many wraps and when the line rolls over on itself in the coil position it keeps the line from pulling out? Temporarily making the saw seem locked?
Everything seems fine and it just pulled and started with no problem except an expectation of it recurring randomly.
I'm no expert but it seems that the cord is suspect. It is very clean also.

Thanks for your reply, that helps in further diagnosis.

From what you mention, it does not sound like the starter cord is too long, like Burnham suggested, maybe add another turn to the starter pawl rotator (white round thing that has the starter cord wind around and the starter pawls on its inside), to give the spring a bit more in return, but if that was the issue, the pull cord/ handle would flop down and get in the way, or not fully retract and in worse case after that, the cord would fall out of the rotator and bind up on the workings inside the stater cover, which this has not done, for now, I say leave it alone unless the cord has actually come out of the rotator, its normal for the cord to wind over itself and cross over at points, ive not seen them bind from that unless there was a separate issue, which you have not mentioned, so I dont think its that.

Starter cord length should be 750mm, the knot in the rotator reduces its overall length etc etc.

One thing a worn rotator can cause is hard pull, and if its really worn, can lock up, but you didnt mention if it had excessive wear in its center where it rotates on the spindle, a little bit of movement on the center is ok, feel free to vid it and post it up, then we can cross that off the list.



I think its one of those things, which has been mentioned above, that some fuel mix/ oil from either pooling in the crank, or transfer port, and it gives the piston a big step up in compression and it catches you out occasionally.
Annoying, but it does happen, do you rev the saw then shut it down as its spooling down, or let it idle for a few seconds after the cut.

hope that helps, lets step thru it methodically, so you dont leap frog over the problem.

 

[Marc-Antoine]

I had the starter chord locked on itself before. It was in my dumb rooky time using a chainsaw, like a "know almost nothing" with a few days once in a year as a training. The starter chord wore out and broke (doomed saw with systematic vapor-lock after running out of gas), so I replaced it by a random thin chord laying around. Too thin of a chord and with a hollow center. So it flattened and was able to slip between the already coiled part of the chord and the rotator's flange. Add to that a cheap plastic rotator on a Macculloth unable to take the side force and you can see why it jammed. Stupidly, I was pissed to see my hack work failing and I had to convince myself that buying the proper thing was maybe not as dumb as I thought first.

 

[Ed L]

See my "thanks stihl" thread, its about 3/4 down the page...
No idea if your saw is made the same way.

Ed