Husqvarna 326C, 326L, 326LX-Series, 326LDX-Series, Руководство по ремонту

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Cylinder and piston
Service tips
Action:
In severe cases – replace the cylinder.
Repair the threads using Heli-Coil.
Polish the damaged area using a fine grade emery cloth
so that the coating of aluminium disappears.
With deep seizure score marks the piston and cylinder
should be replaced.
Replace the cylinder and piston.
Carefully polish the damaged area using a fine file of fine
grade emery cloth. Before the piston is refitted the cylinder
should be polished as above. With deep score marks the
piston and cylinder should be replaced.
Carefully loosen the piston rings and clean the groove well
before refitting. Carbon deposits in the groove impair the
important heat transfer between the piston and cylinder.
NOTE!
Be careful with the lower edge of the piston ring
groove. If this is damaged, or if carbon deposits
remain, the compression pressure can leak
through.
Check the wear on the piston ring by placing it in the lower
part of the cylinder.
Position a suitable punch on the bolt head and give a few
sharp knocks with a hammer. If the bolt still does not loosen,
repeat the procedure.
Defect:
Broken cooling fins, damaged threads or sheared bolts by
the exhaust port.
Seizure marks in the cylinder bore (especially by the
exhaust port).
Surface coating in the cylinder bore worn out (primarily at
the top of the cylinder).
The piston shows signs of seizure score marks.
Piston ring burnt in its groove.
Bolts much too tight in the aluminium material.
Wear tolerances
Cylinder bore Piston ring gap Piston ring groove Piston ring play
When the surface coating
is worn and aluminium
appears. Max. 1.0 mm with the
piston ring inserted in the
lower part of the cylinder. Max. height on a new piston
ring + 0.10 mm.
Max. 0.15 mm. Clean the
groove before checking the
measurement.