MS361 fractured crankcase... what to expect from Stihl?

[lone wolf]

Hello All
Here are some pictures of the mount on my MS 361.

As you can see there is no evidence of cracking on my saw.

Comparing this mount to the mount on an MS 360, there appears to be far less material supporting the mount.

Also in your third picture the mechanism shown is from either an MS 361 C-BQ, MS 361 C-Q, MS 361 C-Q Z or an MS361-RZ all of which have the control handle activated brake so it would be applied every time the user lets go of the control handle. If the chain is still running at a high enough speed it would be putting a tremendous load on the chain brake pivot far more often than the design parameters allow for. Looking at the saws in your rack you can see that they are indeed fitted with the control handle activated brake.

I suspect that the reason most of us have never seen this issue is that we mostly use the standard MS 361 without the control handle activated brake. I suspect that this is an operator issue.

Regards

Phil

If they are using Quick stop saws that would explain it good observation there.

 

[stihlrookie]

Thanks for the pics Phil C

Good eye spotting the rear handle activated Quick Stop feature, CQ. I think you may have nailed it on this one, repeated(overuse) of this wonderful option. The Quick Stop feature may, and I emphasize may, have its benefits in a homeowner/occiasional use saw but being as these particular saws are being used in a production setting it was a poor idea. In the efforts to maintain production I am certain that the saws are not being allowed to spin down entirely before releasing the rear handle and subsequently activating the chain brake, repeatedly throughout a normal work day. Add to that the additional use of the manual chainbrake and the now fractured area is exposed to stress quite possibly hundreds of times a day.

 

[lone wolf]

Good eye spotting the rear handle activated Quick Stop feature, CQ. I think you may have nailed it on this one, repeated(overuse) of this wonderful option. The Quick Stop feature may, and I emphasize may, have its benefits in a homeowner/occiasional use saw but being as these particular saws are being used in a production setting it was a poor idea. In the efforts to maintain production I am certain that the saws are not being allowed to spin down entirely before releasing the rear handle and subsequently activating the chain brake, repeatedly throughout a normal work day. Add to that the additional use of the manual chainbrake and the now fractured area is exposed to stress quite possibly hundreds of times a day.

Add to that a chain spinning a little fast and there it is.

 

[SawTroll]

I am not a surprice at all if the saws are CQ ones - there is a reason that most of us shy them like a plague!:angry2::angry2:

Stihl should of course be notified about it.

 

[lone wolf]

I am not a surprice at all if the saws are CQ ones - there is a reason that most of us shy them like a plague!:angry2::angry2:

Stihl should of course be notified about it.

I had one i sold it .The plastic kept meting in the brake area.Just seemed like it was not a good design.

 

[openloop]

So the brake was doing exactly what it was designed to do then. Stihl designed a saw that is designed to jam on the brake when your hand is removed from the handle, and that inturn over time causes the saw to break. Wonderful.

 

[lone wolf]

So the brake was doing exactly what it was designed to do then. Stihl designed a saw that is designed to jam on the brake when your hand is removed from the handle, and that inturn over time causes the saw to break. Wonderful.

I don't think that one ever got a lot of cheers!

 

[stihlrookie]

Firstly, the CQ option should have never found its way onto a pro saw. Secondly the OP should have realized the implications of such frequent use of said option. Maybe these saws were purchased not knowing full well of the CQ feature, maybe they were purchased with safety in mind for the youngsters. As far as I am concerned this is a design flaw, including this option on a pro grade saw, not necessarily a defect and should be brought to the attention of Stihl. With the litigious nature of society more than likely this design was brought to fruition to combat lawsuits. I guess we are fortunate that it is not included on all chainsaws....yet.

 

[SawTroll]

More C-Q trouble;

LINK.

As I have said before, the feature is disaster waiting to happen! :waaaht:

 

[Phil_C]

So the brake was doing exactly what it was designed to do then. Stihl designed a saw that is designed to jam on the brake when your hand is removed from the handle, and that inturn over time causes the saw to break. Wonderful.

No. True, the idea behind the brake was to activate when your hand left the control handle but that would normally be when you are walking around with the saw idling. Occasionally it would activate in an emergency situation such as if you stumbled when using the saw however it is not meant to be applied when the saw chain is running at top speed every time the operator takes his hand off the handle. From the Stihl website

Secondary Chain Braking System (Q) reduces the risk of injury in select circumstances if so equipped."

Think of it like this, you can sit in your car and pull the emergency/handbrake on and off again as many times as you like and all you may do is wear something out. However drive that car at 55MPH and apply it until your car stops then do the same again and again and something will break. Now you might say "but it is an emergency brake and you should be able to use it as many times as needed" and my reply would be yes it is an emergency brake only to be used in case of an emergency as that is what it was originally designed for.
All these features are thoroughly tested before the saw ever goes to market but if they are used outside the intended use then it becomes a training issue.

Having said the above though, it is a good idea to bring this to the attention of Stihl designers although given that the MS 361 is now a discontinued saw the problem may already have been rectified in the MS 362. I will take a look at my MS 362 later to see if it is heavier duty in that area.

As much as people may dislike the Q brake it is a far better idea than Huskies TrioBrake Also when the quickstop chain brake first came out everyone hated it as well. Now it is standard equipment and most companies (at least here in Australia) will not allow you to use a chainsaw without it.

Interesting thread

Regards

Phil

 

[SawTroll]

....

As much as people may dislike the Q brake it is a far better idea than Huskies TrioBrake .....
Interesting thread

Regards

Phil

I avoid that one as well, and it annoys me that Husky kind of promote it here! :angrysoapbox:

 

[rupedoggy]

I know nothing, until now, of "automatic chainbrakes". If Stihl offers them they should back them. However having said that, The OP could have told us it was that!
Why didn't you tell us that? You have enough saws to know the difference. If you were just trying to get opinions to take to Stihl you DO NOT have permission to use mine. Seems a little sneeky. Can you respond? Mike

 

[Philbert]

None of us know for sure what let to the cracks, we are all just speculating. But as long as we are . . . .

I don't have a 361, and can't tell from the photos, but if someone carried the saw by the chain brake lever instead of the top handle, would that put stress on the stud?

Thanks.

Philbert

 

[dhskier2]

My mistake for not clarifying on these saws. They are in fact CQ model saws; however... the cables were cut (which engages is the CQ feature) after our first season (which was 3 months long. season 2/3 were 8/10 mo's, and we're looking at running a crew 7-9 mo's this year). This was only the case on our original saw purchase (4 of our 5 361's). The 5th 361- the newest of the bunch has not had the cable cut (picture #3). Basically, 4 of 5 saws engage the brake as a standard 361. I would not expect that 3 mo's of running these with the CQ feature would be the cause of this problem.
So why was another 361CQ purchased? It wasn't, at least not intentionally. Ordered a 5th 361 and 2-441's through local dealer for season 2, which is a Bobcat dealership and the only Stihl line they carry in-stock is cut-off saws. When I said "361" they looked at our purchase the previous year and ordered a 361cq.

To respond to a few things that have come up-

1. guys on the crew are assigned a specific saw. The whole goal with that is to give a sense of buy-in that "this is my saw to maintain and take care of for the season." As was mentioned in a couple posts- the saws are in pretty darn good condition for all the use they've seen.

2. Not once on here have I complained, nor do I expect anything fro Stihl with these issues. I've been nothing but happy with the saws, and was very grateful to Stihl when they covered the parts on fixing saw #2. If you'll read my initial post- my question is "what should I expect from Stihl?" not "Stihl better step up and replace my F***ing saws!"

3. I've stated a least once that I'm fully open to operator error, and although most guys on the crews are new to saws, to say these "Kids" are just out there trashing equipment is not the case. As I said, I'll go to the bank on the oversight and leadership of my crew leader.

 

[stihlrookie]

I thought so too

None of us know for sure what let to the cracks, we are all just speculating. But as long as we are . . . .

I don't have a 361, and can't tell from the photos, but if someone carried the saw by the chain brake lever instead of the top handle, would that put stress on the stud?

Thanks.

Philbert

After pulling mine apart I realized the OP was not having trouble with where the chain brake handle attaches to the saw but is actually where the spring and lever attach. It is a stud just in front of chain brake attachment point. Pull the cover off that is behind the side cover and you will see what I mean, or look at Phil C's picture.

 

[openloop]

Well if the cables were cut then I guess the stihl guys cant blame the auto chainbrake anymore.....

That being said If you cut those cables and someone wound up hurt by one of those saws dont you think you are open to getting your ars reamed via lawsuit? You might not think that could happen, but you dont have the same train of thought as a person who just accidentally cut their leg off.

 

[lone wolf]

Well if the cables were cut then I guess the stihl guys cant blame the auto chainbrake anymore.....

That being said If you cut those cables and someone wound up hurt by one of those saws dont you think you are open to getting your ars reamed via lawsuit? You might not think that could happen, but you dont have the same train of thought as a person who just accidentally cut their leg off.

Why did the OP have a need to cut them in the first place?

 

[RED-85-Z51]

Why did the OP have a need to cut them in the first place?

Because its in impractical concept on a pro saw...

 

[Philbert]

STIHL 'likes' conservation corps activities on their facebook site:

Wyoming Conservation Corps - YouTube

Philbert

 

[Phil_C]

My mistake for not clarifying on these saws. They are in fact CQ model saws; however... the cables were cut
.

I thought after reading the above I had this issue figured out but then I read the

the newest of the bunch has not had the cable cut (picture #3).

I am no longer so sure. I thought that cutting the cable may have put more load on the pin due to the activation lever of the auto chain brake floating into an abnormal position but if it is happening with the unmodified saw as well then I am at a loss to explain it.

What else did you do to the auto chain break? On my MS280 if I cut the cable the brake would be engaged all the time.

Also I apologize if my comments came across as trying to say your crews are deliberately trashing the saws. My aim was to point out that perhaps through their lack of knowledge they were using the saws outside of the original design specs for the saws.

Two things I would be doing if I was in your situation with the three cracked saws A) In order to prevent the cracks from getting worse, and if possible, pop rivet or bolt a plate around the cracked area or get someone to weld the cracked areas, and B) replace the auto chain brake mechanism with the standard type 1128 160 5000.

Eventually though you are most likely going to have to replace the cases. If Stihl comes to the party again then all well and good but you can always look on ebay. There is one crank case for an MS361 for sale on Ebay now.

Regards

Phil