Stihl MS 172 User Manual

0000-GXX-1220-A1
► File down the depth gauges with a flat file so
that they are level with the STIHL filing gauge
and parallel to the service mark. The STIHL fil‐
ing gauge must match the chain pitch.
► If you have any queries: Contact your STIHL
servicing dealer for assistance.
17 Repairing
17.1 Repairing the Chain Saw,
Guide Bar and Saw Chain
The chain saw, guide bar and saw chain cannot
be repaired by the user.
► If the saw, guide bar or saw chain is damaged:
Do not use your saw, guide bar or saw chain,
and contact your STIHL servicing dealer.
18 Troubleshooting
18.1 Troubleshooting the Chainsaw
Most problems can be attributed to the same cause.
► Carry out the following measures:
► Clean the air filter.
► Clean or replace the spark plug.
► Adjust the idle speed.
► If the problem continues: Carry out the measured listed below.
Fault Cause Remedy
The engine does not
start.
There is not enough
fuel in the fuel tank.
► Mix the fuel and top up the chainsaw.
The engine has floo‐
ded.
► Vent the combustion chamber.
The carburetor is too
hot.
► Allow the chainsaw to cool down.
► If a manual fuel pump is fitted: Press the manual fuel
pump at least 10 times before starting the engine.
The carburetor has
iced up.
► Allow the chainsaw to warm up to +10 °C.
The engine idles
erratically.
The carburetor has
iced up.
► Allow the chainsaw to warm up to +10 °C.
The engine stops
while idling.
The carburetor has
iced up.
► Allow the chainsaw to warm up to +10 °C.
Poor acceleration. The saw chain is
over-tensioned.
► Tension the saw chain as specified.
The saw chain does
not start running
when revved up.
The chain brake is
engaged.
► Disengage the chain brake.
The saw chain is
over-tensioned.
► Tension the saw chain as specified.
The sprocket nose of
the guide bar is
blocked.
► Clean the sprocket nose of the guide bar with STIHL
resin solvent.
Engine does not
reach maximum
power.
The muffler is soiled. ► Contact a STIHL servicing dealer.
Smoke or burning
smell while cutting.
The saw chain has
not been correctly
sharpened.
► Sharpen chain as specified.
English 17 Repairing
26 0458-200-0121-B

Stihl MS 172 Specifications

General

Sound pressure level	100 dB(A)
Sound power level	113 dB(A)
Displacement	31.8 cc (1.9 cu in)
Saw chain pitch	3/8"
Recommended bar length	30-35 cm (12-14 in)