Section C3 - Royal Enfield SPRING FRAME O.H.V. 250cc CLIPPER 1954 Workshop Maintenance Manual

ROYAL ENFIELD WORKSHOP MANUAL
Service Operations with Engine in Frame
1. Removal of Timing Cover
First place a tray under the engine to catch the oil
which will escape when the cover is removed.
Remove the exhaust pipe and silencer.
Remove nine screws from the cover, taking care not
to lose the sealing washers, one for each screw.
Draw off the timing cover, tapping it lightly if
necessary.
In refitting the timing cover see that the joint washer
is correctly located over the oil holes, using a little
grease (not compound) to hold it in position.
See that the cork or rubber plug is in position in the
hole in the pump worm. If the plug is damaged it should
be renewed to ensure oil pressure to the big end bearing.
When refitting the timing cover it is important that
the engine is turned gently forwards while the cover is
being put in place. This will help the engagement of the
pump worm with the pump spindle and prevent damage
to the gears.
The filter chamber should be filled with clean oil
before the timing cover is refitted.
To verify that the oil pumps are working after
replacing the timing cover, start the engine up and

SECTION C3

250 Clipper
remove the oil filler cap so that the oil return through
the relief valve can be seen. It may take several minutes
before there is sufficient oil in the engine for the return
flow through the relief valve to commence.
2. Valve Timing
The cams are integral with the cam pinions and the
position for correct timing is marked on the pinions by
small dots.
Rotate the engine to top dead centre and put the
exhaust (or right hand) cam pinion in position so that
the pair of dots on it are opposite the pair of dots on the
timing pinion on the crankshaft.
Put the inlet (or left hand) cam pinion in position so
that the single dot on it is opposite the single dot on the
exhaust cam pinion.
The correct timing at .012 in. clearance is as
follows:-
Exhaust opens 75° before bottom dead centre.
Exhaust closes 35° after top dead centre.
Inlet opens 30° before top dead centre.
Inlet closes 60° after bottom dead centre.
Section C3 Page 1 Section C3 Page 1