18
WORKSHOP MANUAL
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Suggestion:
Use grease (f.ex.PM-NH2, LITOL 24,
CASTROLEASE LH-2 ...) to avoid needles falling out of
countershaft bearings.
2.3.
Gearbox – shifting, crank mechanism
With the engine in this dismantled condition, it is
possible to repair the gearbox and the gear shift
mechanism. Without pressing the crankshaft mechanism
out of the other crankcase half. During the inspection of
gearbox and gearshifting, remove the shifter fork rod,
the shifter forks, the layshaft and the gears. With soft
mallet tap the mainshaft out of bearing. If it is necessary
to remove the gear shift plate, remove the four, dot
secured countersink screws from the gate, turn the gate
to suitable position and remove it from case
To remove the crankshaft screw the S-85
drag with two M8 screws into the threaded
holes for fastening screws of left half
crankcase cover. Push out the crankshaft out
of left half of case.
Remember:
connecting rod must be in its top (T.D.C.)
2.4. Exchange of layshaft needle bearings
After removing locks drive the bearing into the
crankcase with a drift. To facilitate this job, remove the
speedometer drive from left half of engine. Put new
bearings into the crankcase – heat case to 80-120°C.
After pressing them home, fill them up with grease to
avoid loosing of needles.
2.5.
Testing the evenness of seating surfaces
Clean thoroughly the seating surfaces and test
the evenness of the whole engine housing with the steel
ruler. Grind the surfaces plain on a plate if necessary.
Clean the ground surfaces thoroughly of the grinding
paste.
2.6.
Exchange of bearings and seal rings of
crankshaft mechanism
Change bearings in case they are noisy or worn
out. Dismantle the engine housing, remove the lock rings
of sealing rings. Heat the case up to 100-120°C and using
the drift S-71 drift the bearing into the engine case. Use
drift S-72 to drift out the sealing ring (from inside-out).
Mainshaft bearing drive out similar way.