STIHL 064, 066 25
Reassemble in the reverse sequence.
Important: A modified cylinder (with
extended exhaust flange) is installed from
machine number X 18 760 750. A gasket and
flange are required to fit a new muffler on an
original-type cylinder.
Only the new version of the muffler may be
fitted to the new cylinder.
Note: Fit a new exhaust gasket. Coat threads
of screws with Loctite, see 12.2. Tighten
screws of original-type lower casing to 10 Nm
(7.5 Ibf.ft) and screws of new version to
15 Nm (11.0 Ibf.ft). Tighten screws of upper
casing to 8 Nm (5.9 Ibf.ft).
Troubleshooting chart - see 2.2. - Remove the gasket and flange,
if fitted.
- Take out the upper casing mount-
ing screws and remove upper - Inspect the spark arrestor
casing. screen, if fitted. If necessary,
bend back the retaining tabs
- Take out the lower casing mount- and pull out the screen.
ing screws and remove lower
casing. - Clean the spark arrestor screen
or fit a new one.
4. ENGINE
4.1 Removing and Refitting
Exhaust Muffler
Top:
Top: Removing exhaust gasket 1 = New muffler
Upper casing mounting screws 2 = Gasket
Bottom: 3 = Flange
Bottom: 1 = Retaining tabs 4 = Gasket
Lower casing mounting screws 2 = Spark arrestor screen 5 = Cylinder (original version)