Standard Setting - Stihl MS 311 Manual

: To adjust the high speed screw
(H), insert the screwdriver (1)
5910 890 2304 through the
opening (arrow) and push the
pre-installed limiter cap into the
high speed screw (H).
Adjust idle speed with a tachometer.
Adjust specified engine speeds
within a tolerance of ± 200 rpm.
1. Adjust engine speed idle speed
screw (LA) to 3,300 rpm.
2. Turn the low speed screw (L)
clockwise or counterclockwise
to obtain the maximum engine
speed.
If this speed is higher than
3,700 rpm, abort the procedure and
start again with step 1.
3. Use the idle speed screw (LA)
to set the engine speed again to
3,300 rpm.
4. Set the engine speed to
2,800 rpm with the low speed
screw ( L).
5. Set engine's maximum speed to
13,000 rpm with the high speed
screw (H).
80
1
: Push a suitable drift through the
opening (arrow) and push home
the limiter cap until it is flush with
the carburetor body.
This completes the basic setting of
the high speed screw (H) and the
low speed screw (L) and the high
speed screw (H) is locked.

12.7.2 Standard Setting

The limiter cap must not be
removed for the standard setting.
Always perform the following steps
before carrying out any
adjustments:
– Troubleshooting, b 3.6
– Check chain tension and adjust if
necessary.
– Inspect the spark arresting
screen (if fitted) and clean or
replace if necessary, b 3.7 or
b 6.1
– Check the air filter and clean or
replace if necessary, b 12.1
MS 311, MS 391