MCW
Somebody's talking crap here & it ain't the tree!
I hadn't even looked close enough to notice the symbols
The part you refer to is for summer or winter operation. In winter mode warm air is directed over the carburettor.
Ongoing MS 200T Carburetor Issue
- Thread starter HandLogger
- Start date
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I hadn't even looked close enough to notice the symbols
The part you refer to is for summer or winter operation. In winter mode warm air is directed over the carburettor.
HandLogger
ArboristSite Operative
Winter Operation
At this point, we've got parts schematic drawings and a service manual for the MS 200T, but damn if I could find the owner's manual anywhere. Consequently, I did a bit more research, found a .pdf version of the owner's manual and, there it is, on Page 25. The paragraph is entitled Winter Operation, which states:
Thanks, MCW, you were right on the money about the seasonal purpose of this relatively obscure part. :msp_thumbup:
At this point, we've got parts schematic drawings and a service manual for the MS 200T, but damn if I could find the owner's manual anywhere. Consequently, I did a bit more research, found a .pdf version of the owner's manual and, there it is, on Page 25. The paragraph is entitled Winter Operation, which states:
At temperatures below about +50°F
- Take out the screw (1).
- Pull out the shutter (2), turn it over so that the window is facing down and then push it back into position [NOTE: so that you see the snowflake].
- Refit the screw (1).
The shutter is now in the winter position. Heated air is now drawn in from around the cylinder to help prevent air filter and carburetor icing.
- Take out the screw (1).
- Pull out the shutter (2), turn it over so that the window is facing down and then push it back into position [NOTE: so that you see the snowflake].
- Refit the screw (1).
The shutter is now in the winter position. Heated air is now drawn in from around the cylinder to help prevent air filter and carburetor icing.
Thanks, MCW, you were right on the money about the seasonal purpose of this relatively obscure part. :msp_thumbup:
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mp5n
ArboristSite Operative
Carb problem fixed!
I’ve been keeping an eye on this thread. 2 of my saws were exhibiting the same poor idle and big dead spot on acceleration. I’ve had to open up the L screw a few turn to try and get them to run, but didn’t have any luck. I disassembled the accelerator pump and the o-rind was definitely wasted. I bought replacement Viton O-rings through McMaster-Carr, McMaster-Carr. The number is #9263K511, $6.08 for 25pcs.
As soon as I swapped them out the saws ran perfectly. I was able to get the L screw back where it belonged and the snap in the throttle is back. If anyone is experiencing the same symptoms I would definitely recommend giving this a try before swapping out a carb.
These are definitely something any bearing supply can provide. The dimensions are 3mm ID x 1mm width. The standard Viton is recommended for petroleum and chemical resistance, although Buna-N will work also.
MP5N
I’ve been keeping an eye on this thread. 2 of my saws were exhibiting the same poor idle and big dead spot on acceleration. I’ve had to open up the L screw a few turn to try and get them to run, but didn’t have any luck. I disassembled the accelerator pump and the o-rind was definitely wasted. I bought replacement Viton O-rings through McMaster-Carr, McMaster-Carr. The number is #9263K511, $6.08 for 25pcs.
As soon as I swapped them out the saws ran perfectly. I was able to get the L screw back where it belonged and the snap in the throttle is back. If anyone is experiencing the same symptoms I would definitely recommend giving this a try before swapping out a carb.
These are definitely something any bearing supply can provide. The dimensions are 3mm ID x 1mm width. The standard Viton is recommended for petroleum and chemical resistance, although Buna-N will work also.
MP5N
HandLogger
ArboristSite Operative
Good on ya!
Before I go on, I want to make it clear that having a useful thread for MS 200T owners was -- and still is -- the sole purpose of this thread.
There's really no way for me to know how many reading this thread know this or not, so I'll just write it -- a lot of what I've learned about all of our Stihl saws came from one source: Lakeside53 (aka, Andy or Lake). The dude was a wealth of information, and he is sorely missed by all of us who operate saws more than we work on them. This clearly being true, I read through every MS 200T thread I could get my eyes on -- that Lakeside53 posted in -- before I wrote the initial post in this thread. And to make a very long story a bit shorter, the consensus was that the Zama accelerator pump design is one of the major causes of poor 200T performance issues.
Specifically, the O-ring on the pump's piston/plunger wears out relatively quickly which eventually leads to metal to metal wear occurring between said piston/plunger and the carburetor body itself. If caught early enough, YES, by all means, replacing the O-ring can save the day. If your work situation is anything like ours, however, you may not have the time to perform multiple repairs on a faulty carb design. This is the reason that a new non-accelerator pump Zama carburetor was purchased and installed on the MS 200T that inspired this thread. In short, it was worth it to us to spend the money on a better designed carb than it was to go through repairing the original carb, which, by the way, starting giving us headaches after relatively low operating hours.
We still have an adjustment grommet and an airbox backing plate on order, so I haven't had anything new to report lately. Once I have these parts installed, and we have some solid run time on the saw, I will be sure to add a progress report to this thread.
Thanks to all who've made this a thorough thread :msp_thumbup:
P.S. There's a link to a video in this thread -- in Post 16 -- that shows MCW's "converted" accelerator pump-less MS 200T in action. I believe this video conclusively demonstrates how the older Zama carburetor design can be employed on an MS 200T. His saw kicks arse. Thanks for all of your posts, MCW.
Before I go on, I want to make it clear that having a useful thread for MS 200T owners was -- and still is -- the sole purpose of this thread.
There's really no way for me to know how many reading this thread know this or not, so I'll just write it -- a lot of what I've learned about all of our Stihl saws came from one source: Lakeside53 (aka, Andy or Lake). The dude was a wealth of information, and he is sorely missed by all of us who operate saws more than we work on them. This clearly being true, I read through every MS 200T thread I could get my eyes on -- that Lakeside53 posted in -- before I wrote the initial post in this thread. And to make a very long story a bit shorter, the consensus was that the Zama accelerator pump design is one of the major causes of poor 200T performance issues.
Specifically, the O-ring on the pump's piston/plunger wears out relatively quickly which eventually leads to metal to metal wear occurring between said piston/plunger and the carburetor body itself. If caught early enough, YES, by all means, replacing the O-ring can save the day. If your work situation is anything like ours, however, you may not have the time to perform multiple repairs on a faulty carb design. This is the reason that a new non-accelerator pump Zama carburetor was purchased and installed on the MS 200T that inspired this thread. In short, it was worth it to us to spend the money on a better designed carb than it was to go through repairing the original carb, which, by the way, starting giving us headaches after relatively low operating hours.
We still have an adjustment grommet and an airbox backing plate on order, so I haven't had anything new to report lately. Once I have these parts installed, and we have some solid run time on the saw, I will be sure to add a progress report to this thread.
Thanks to all who've made this a thorough thread :msp_thumbup:
P.S. There's a link to a video in this thread -- in Post 16 -- that shows MCW's "converted" accelerator pump-less MS 200T in action. I believe this video conclusively demonstrates how the older Zama carburetor design can be employed on an MS 200T. His saw kicks arse. Thanks for all of your posts, MCW.
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I think the kit with the plunger was only $8.50 from Stihl.
Somebody earlier, I think it was Belgian, just replaced the O -ring.
Not much cost and a little trouble. Works for me.
If it goes bad any time soon please post, although I can't see any reason why you wouldn't get the same amount of use as a new one.
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HandLogger
ArboristSite Operative
I can't speak for other areas of the country, but the plunger plunger/piston kit that was recommended earlier in this thread is no longer available from Stihl dealers in our area.
I bought one in December. It wasn't in the regional warehouse and was backordered to wherever. Took about a week to get it.
But, unless the piston is badly worn I suspect a new O ring would do the same thing since the piston really shouldn't have any pressure on it unless the O ring has worn even with it.
MCW
Somebody's talking crap here & it ain't the tree!
No problemo
I enjoyed the thread as much as anybody. It's not often I can contribute anything regarding saw mechanics as most other people beat me too it and know a lot more than me. Like my local Stihl dealer If I ever have issues again though I'll be referring back to this thread.
