just take the tabs off right?

Arborist Forum

Help Support Arborist Forum:

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

SPDRMNKY

ArboristSite Dork
Joined
Nov 23, 2010
Messages
670
Reaction score
466
Location
Kansas
I set about today to take the limiting tabs off the carb screws on my two EPA-afied saws

the MS361 couldn't have been simpler...pull the carb off, pull the plastic thingies out, cut the tabs with a razor blade, put the plastic thingies back on, reassemble, tune (about 1/4 turn richer on H)...done

**the one note here is that instead of the left-hand thread puller tool, or a wood screw, I used an old set of needle-nose pliers I have that I previously filed the tips down on (for something on my Jeep)...into the notch next to the plastic thingy, grab and pull

the MS261 was a PITA, so there are some pics...I couldn't find MCW's thread (or any others) on the same, so it was a bit of trial and error...for reference my MS261 is only 2 months old, and part of me suspects that the carb screw limiter design has recently changed...let me know!:msp_unsure:

to start, getting the kill switch disconnected from its wires is a chore...be careful or you'll crack some plastic...like I did...I don't like my method, so no pics of that

once the carb was off, I could look at the screws better...the L screw seems to have no limiting mechanism at all, but rather a nice little funnel cap that helps center your screwdriver...cool:msp_thumbup:

the H screw was apparently secured inside a metal tube that came off the side of the carb, and had a metal funnel cap that showed no obvious way to remove it...eventually I saw a little mark on the funnel cap that lined up with some sort of tab I could barely see inside when it was adjusted out against the stop...so I used an easy-out (gently) and pulled (firmly), and the metal funnel cap popped off

this is what was inside...that tube is about 1/2" deep (on the top left)

IMG_20110702_122559.jpg


now a 2mm allen fits into the end of the screw, and I found that one of those tabs inside hit against the metal tab built into the tube wall, but the other didn't...ok...so I tried an exacto knife, but couldn't reach quite far enough

so I made this little chisel out of scrap metal I had lying around

IMG_20110702_125352.jpg


I used the improvised chisel to shave off plastic from the bigger tab, until it would clear the metal tab built into the wall

then I put the metal funnel cap back on, but still was hitting a stop...so pulled it back off and found that part of its wall was thicker, and was obviously hitting the metal tab built into the wall

so I filed that down too
(here you can also just barely see the two notches in the end of the metal funnel cap that engage those two plastic tabs in the tube)

IMG_20110702_131306.jpg



this time, when I reassembled, there was no limit to adjustment

so I put everything back together, and tuned her (about 1/4 turn richer on H)...she runs much stronger now

----------

yes, I still tune by ear ;)...yes, both saws are stock...yes, I err to rich...yes, I know I just jeopardized my 2 yr warranty on the 261

so are all 261 carbs like that on the H screw, or is this metal tunnel, metal hat, double tab thingy a new development?

cheers!
 
Ive never done a stihl but normally use a dremel tool with a small burr ball end ,just go in and grind off the plastic wing on the limiter cap so you can have 360 rotation on both screws . usually dont even have to dismantle anything ,cept maybe the air filter . its always good to have complete control of the fuel/air mixture for top perf jk
 
Fellas,

I know I tend toward long-winded in my threads, but I wanted to bring this back to the top (now that the 4th is over), and get your inputs.

Cheers!
 

Latest posts

Back
Top