Wear Tolerances; Assembly - McCulloch T22LS Workshop Manual

Wear tolerances

Cylinder bore
When the surface coating is
worn and aluminium appears.
Cylinder and piston
Piston ring gap
Max. 1.0 mm with the piston ring
inserted in the lower part of the
cylinder.

Assembly

Lubricate the gudgeon pin's needle
bearing with a few drops of engine oil
and assemble the piston.
NOTE!
Place a rag in the crankcase opening to prevent the circlip from falling into
the crankcase in case it should fl y out.
Check that the circlip is correctly fi tted into the groove by turning it with a
fl at nosed pliers.
Check that the pulse channel (A) in the
cylinder is open.
Assemble the cylinder with the help of
assembly set 502 50 70-01.
502 50 70-01
Piston ring groove
Max. 1.6 mm. Clean the
groove before checking the
measurement.
Assembly
Lubricate the gudgeon pin's needle
bearing with a few drops of engine oil
and assemble the piston.
Lubricate the gudgeon pin's needle
bearing with a few drops of engine
oil. Place a distance washer on each
side of the needle bearing. Turn the
countersunk end toward the needle
bearing.
Direct the arrow on the top of the piston
towards the exhaust port.
Press in the gudgeon pin and fi t the
circlips.
Check that the pulse channel (A) in the
cylinder is open.
Place a new cylinder base gasket on the
cylinder or the crankcase. Lubricate the
piston and the crank bearing with a few
drops of engine oil.
Assemble the cylinder with the help
of the piston ring compressor in the
assembly set 502 50 70-01.
Tighten the cylinder against the
crankcase.
NOTE!
Do not twist the cylinder when
sliding it down over the piston.
There is a risk that the piston ring
may break.
Piston ring play
Max. 0.15 mm. Clean the
groove before checking the
measurement.
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