Need help with adjustment instructions

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

HandLogger

ArboristSite Operative
Joined
Sep 26, 2007
Messages
237
Reaction score
65
Location
NE
Our MS200T has been extremely sensitive to filter cleanliness lately, so I decided that it was running on the rich side and that an adjustment was in order. Perhaps this is the root cause of the current problem, but I attempted to use our Stihl Instruction Manual (Page 32) to adjust the saw's carburetor.

Under the heading of "Standard Setting," the manual tells the user to:

(1) Shut off the engine -- Well, I started the adjustment procedure without running the saw first (and after reading Madsen's adjustment procedure, I learned [later] that this was Mistake #1).

(2) Check the air filter and clean or replace, if necessary -- I replaced the air filter before I started this, so this is the one thing I did correctly.

(3) Check the spark arresting screen (country-specific) in the muffler and clean or replace, if necessary -- Our saw doesn't appear to have any type of screen whatsoever in the exhaust.

(4) Turn high speed screw (H) CCW as far as stop (no more than 3/4 turn) -- I interpreted this to mean that you turn the (H) screw CW until it stops and, afterword, you turn the same screw CCW 3/4 turn. Turning the (H) screw CW until it stops is simple enough, but the 3/4 turn is another story. On our saw, the (H) screw will not make 3/4 turn before it is max CCW.

(5) Carefully turn the low speed screw (L) down onto its seat (clockwise) -- I slowly turned the (L) screw max CW.

(6) Open the low speed screw (L) one full turn -- I used the notch on the small adjustment screwdriver I got from our Stihl dealer and turned the (L) screw CCW one full turn.

And now the results:

After reading the Madsen's adjustment procedure, I have no doubt that my first attempt at adjusting a saw carburetor was severely flawed; consequently, the saw wouldn't fire at all. And after getting that old familiar "This ****ing saw is flooded!!!" phrase ringing in my head, I replaced the spark plug and began making minor adjustments to both screws until the saw finally came to life. The saw will run now, in short, but all manner of minor adjustments will not get the saw to rev up properly when the throttle is squeezed.

The one good thing is that the saw can at least be warmed up now. Nevertheless, both written adjustment procedures I've read -- the Stihl Instruction Manual and Madsen's -- seem to indicate that both the (H) and the (L) adjustment screws should have more travel than what I'm experiencing with our saw. In fact, the imprints under the adjustment screw holes on our saw clearly indicate that we should be getting at least 3/4 turn CCW out of the (H) screw.

If anyone on the board can decipher this mess and put me back on the right track, I'd be much obliged. If nothing else, I'd greatly appreciate an explanation of what Step 4 (above) actually means.

A visit to the nearest Stihl dealer would be a logical step, no doubt, but the "nearest" dealer is a long way from the woods we're working in and, like a lot of folks these days, we're very short on funds.

Thanks very much for any constructive thoughts ... :)
 
Last edited:
No experience with that model, but many newer saws have limits on how much the carb screws can be turned.

Usually the limit takes the form of a plastic sleeve with a tab that slides over the carb screw. It's usually possible to pull this sleeve, trim off the tab, and reinstall the sleeve.

The H screw should be set to the WOT spec with a tach.

The L screw should be set to best idle at the specified idle RPM.

Each screw affects the other so more than one adjustment may be required.
 
when in doubt 3/4 turn out on both to begin then go 1/4 turn out on each if that dont work check the impulse line under the left side of handle near back of air filter plate with a flashlight to see if disconnected.If the h screw stops when you turn it out that is where the factory set it. If it still wont run right change the gas filter.
 
I just learned recently from my saw shop, and have heard it here numerous time's. Pull off the limiter caps'. The only way you can tune, and adjust the carb properly.
 
Trying to adjust out a fuel problem is a bad idea, you need to fix it.

Go through the carb, and inspect the fuel line and filter first.
 
Trying to adjust out a fuel problem is a bad idea, you need to fix it.

Go through the carb, and inspect the fuel line and filter first.

do not take the carb apart unless you are so experienced!Unless your feeling lucky well are you?what exactly was it acting like before you moved the jets?
Just looked at mine its 1 out on the h and 3/4 out on low try that.
 
Last edited:
I agree, but first I would pull the cap's too seat the adjustment screw's all the way in, that way you could start from scrath, and eliminate one problem. Bet you flooded it. Re zero the adjustmen's, and give it a try.
 
Thanks for the replies, fellas :)

Lone Wolf: To answer your question, the saw would bog when the throttle was squeezed -- until the air filter was either cleaned or replaced. As I mentioned in the original post, this lead me to believe that the saw was running rich (starved for air). Do you happen to have a digital camera? If so, I'd like to see where the "impulse line" is located.

NormZilla44: Please elborate on the "limiter caps." I'm assuming that they limit the RPMs, but where are they located on the MS200T?

The fuel filter suggestions are well taken -- I'll definitely do that as soon as possible.

Thanks very much for your time ...
 
Last edited:
Thanks for the replies, fellas :)

Lone Wolf: To answer your question, the saw would bog when the throttle was squeezed -- until the air filter was either cleaned or replaced. As I mentioned in the original post, this lead me to believe that the saw was running rich (starved for air). Do you happen to have a digital camera? If so, I'd like to see where the impulse line is located.

NormZilla44: Please elborate on the "limiter caps." I'm assuming that they limit the RPMs, but where are they located on the MS200T?

The fuel filter suggestions are well taken -- I'll definitely do that as soon as possible.

Thanks very much for your time ...

He is talking about plastic covers on your hi and low adjustment screws on your carb that limit the adjustment you can make to a 1/4 of a turn. You need to remove them I am not familiar with that saw but usually you can take a wood screw and screw it in the middle of the plastic limiter and screw it while it pulls the limiter off so you can make adjustment on it.
 
He is talking about plastic covers on your hi and low adjustment screws on your carb that limit the adjustment you can make to a 1/4 of a turn. You need to remove them I am not familiar with that saw but usually you can take a wood screw and screw it in the middle of the plastic limiter and screw it while it pulls the limiter off so you can make adjustment on it.

Look between the top of the saw body and under handle by air filter on left if you cant find it Ill send a digital photo.Also click on the ms200t on the bottem of my page for a parts diagram.Just looked at mine it is exactly above the gas cap and slightly forward a little in the space between the bottem of air filter box and saw body.
 
Last edited:
Look between the top of the saw body and under handle by air filter on left if you cant find it Ill send a digital photo.Also click on the ms200t on the bottem of my page for a parts diagram.

From the diagram only the high has a limiter cap.
 
I think I'm following you, jrr344. Page 13 of the parts diagram -- reference the MS200T link on Lone Wolf's signature block -- shows a "Cap" as Reference ID #25 (assuming that our carburetor is a C1Q-S61).

I studied said diagrams, Lone Wolf, and I couldn't find the drawing of the "impulse line" you referred to. Don't mean to impose on you too much, but can you identify the part on your drawing?
 
I think I'm following you, jrr344. Page 13 of the parts diagram -- reference the MS200T link on Lone Wolf's signature block -- shows a "Cap" as Reference ID #25 (assuming that our carburetor is a C1Q-S61).

I studied said diagrams, Lone Wolf, and I couldn't find the drawing of the "impulse line" you referred to. Don't mean to impose on you too much, but can you identify the part on your drawing?

Get a flashlight look above the gas cap in the space between the case and left side air box if that dont work give me your cell number and ill help.
 
Sorry, Lone Wolf. I should've told you that I wasn't in front of the saw right now. That's why I was studying the diagrams linked to your signature block. I've got to travel a ways to get to the work site, but I will definitely study it the next time I'm there.

Thanks for your time ... :)
 
Sorry, Lone Wolf. I should've told you that I wasn't in front of the saw right now. That's why I was studying the diagrams linked to your signature block. I've got to travel a ways to get to the work site, but I will definitely study it the next time I'm there.

Thanks for your time ... :)

Pm me if you need help
 

Latest posts

Back
Top