Section C14 - Royal Enfield 350 BULLET 1956 Workshop Maintenance Manual

ROYAL ENFIELD WORKSHOP MANUAL
Service Operations with Engine in Frame
" 350 and 500 Bullet," 1956 -62, " 350 Clipper "
1. Removal of the 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 ten 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 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
remove the oil filler cap so that the oil return
SECTION C 14
and Trials "Works Replica" 1958 -62
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. tappet clearance
is as follows
"350 Bullet"
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.
"500 Bullet"
Exhaust opens 75° before bottom dead centre.
Exhaust closes 35° after top dead centre.
Inlet opens 40° before top dead centre.
Inlet closes 70° after bottom dead centre.
3. Tappet Adjustment
The tappets are adjusted by the ball and socket
joints which are located in a compartment at the
side of the cylinder and access to which is obtained
by removing the inspection cover.
Before checking the clearance or making any
adjustment, rotate the engine until the piston is at
the top of the firing stroke. This will ensure that
both valves are closed and that the tappets are
well clear of the silencing ramps on the cams. If
the cylinder head has been dismantled, make sure
that the end caps have been put back on the valve
stems.
Later type "350 and 500 Bullet" valves have
hardened ends and are not fitted with detachable
end caps.
Because of the ball and socket joints at the
bottom of the push rods, the tappet clearance
cannot be measured there, but between the valve
Section C14 Page 1