Dismantling - Husqvarna 125C Workshop Manual

6
Cylinder, piston, crankshaft, crankcase
The cylinder and the piston are two of the components exposed to most strain in the engine. They must
withstand, for example, high speeds, large temperature swings and high pressure. Moreover, they must be
resistant to wear. Despite these tough working conditions, major piston and cylinder failure is relatively
uncommon. The reasons for this include new coatings in the cylinder bore, new types of oil and grease
and refined manufacturing techniques.
When servicing these components, cleanliness is of the utmost importance. It is therefore recommended
that the cylinder and the area around it be thoroughly cleaned before being dismantled from the
crankcase.
38

Dismantling

Dismantle the engine completely to
gain access to the piston and
crankshaft.
Remove the 4 screws and lift off the
lower crankcase half.
502 71 27-01
Pull out the piston from the cylinder.
Remove the circlips from the gudgeon
pin.
Dismantling
The special design with the combined
cylinder and upper crankcase half
means that the engine must be
dismantled completely to gain access
to the piston and crankshaft.
See relevant chapters for detailed
information if necessary.
Remove the 4 screws holding the
crankcase halves together.
Lift off the lower crankcase half.
Note how the crankshaft is assembled
in relation to the cylinder to prevent
incorrect assembly at a later stage.
Pull the piston straight out of the
cylinder. The piston ring can break if it is
twisted.
Using long-nose pliers remove the
gudgeon pin circlips.
Keep your thumb over the circlip to
prevent it from flying out.