Husqvarna 131RB Workshop Manual page 56

Item Particles of unwanted material
Unsatisfactorily filtered air that moves through the carburetor and into the engine causes damage to the
cylinder and piston. The increased wear is seen on the inlet side of the piston. The wear starts at the
lower edge of the piston skirt.
8 Small score marks and a matt, gray surface
from small dirt particles on the inlet side of
the piston.
9 Inlet side. Dirt from particles on the top of the
piston and in the piston ring groove. The pis-
ton ring is held tightly in the groove. Piston
material is worn off. The lower part of the pis-
ton skirt is thinner on the inlet side than on
the exhaust side.
10 Larger, softer particles that enter the engine
cause damage to the piston skirt below the
piston ring.
11 Larger, harder particles that enter the engine
cause damage to the bottom of the piston
skirt.
56 - Repair instructions
Cause
Defective air filter. Small dirt
particles move through the
filter.
The filter is worn out be-
cause of too much cleaning
and small holes show in the
material.
Incorrect filter maintenance,
such as incorrect procedure
or incorrect cleaning agent.
Air filter material becomes
loose and holes show.
Air filter incorrectly attach-
ed.
Air filter damaged or miss-
ing.
Defective air filter. Small dirt
particles move through the
filter.
The filter is worn out be-
cause of too much cleaning
and small holes show in the
material.
Incorrect filter maintenance,
such as incorrect procedure
or incorrect cleaning agent.
Air filter material becomes
loose and holes show.
Air filter incorrectly attach-
ed.
Air filter damaged or miss-
ing.
Air filter incorrectly attach-
ed.
Air filter damaged or miss-
ing.
Air filter damaged or miss-
ing.
Parts from the carburetor or
inlet system have come
loose and entered the en-
gine.
Procedure
Attach a new filter of correct
type.
Examine the filter carefully
for holes and damage after
cleaning. Replace the filter
if it is necessary.
Clean more carefully and
use the correct cleaning
agent, for example warm
soap water. Replace the fil-
ter.
Attach the filter correctly.
Attach a new air filter.
Attach a new filter of correct
type.
Examine the filter carefully
for holes and damage after
cleaning. Replace the filter
if it is necessary.
Clean more carefully and
use the correct cleaning
agent, for example warm
soap water. Replace the fil-
ter.
Attach the filter correctly.
Attach a new air filter.
Attach the air filter correctly.
Attach a new air filter.
Attach a new air filter.
Do maintenance regularly.
627 - 002 - 23.04.2018