Royal Enfield 350 BULLET 1956, Руководство по техническому обслуживанию мастерской

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ROYAL ENFIELD WORKSHOP MANUAL
Section C14 Page 3
6. Removal of the Cylinder Head
"350 Bullet," "350 Clipper," "Works
Replica" and early "500 Bullet"
Remove the petrol tank (see Subsection 5).
Disconnect the engine steady.
Disconnect the plug lead and oil pipe.
Remove the exhaust pipe.
Push the carburettor back clear of the studs
after removing the fixing nuts.
Remove the rocker box covers.
Remove the decompressor cable from the
lever on the handlebar.
Turn the engine until both valves are closed.
Remove the rockers and bearings complete by
undoing four 1/4 in. nuts on each.
Lift out the push rods.
Remove six nuts, taking care not to lose the
washers.
Remove the 1/4 in. nut above the tappet chest
to avoid possible damage to the crankcase.
Lift the cylinder head off the barrel, tapping it
gently beneath the exhaust and inlet ports with a
hide hammer to break the carbon seal. Do not tap
the fins.
When fitting the head again, apply jointing
compound to both sides of the gasket, replace the
six nuts and tighten them progressively and
diagonally from one side to the other to prevent
distortion.
Replace the 1/4 in. nut above the timing
chest.
Replace the push rods with the adjustable parts
downwards, remembering that the shorter rod is
the inlet.
Replace the rockers and bearings, making sure
that the oil feed holes are at the bottom and that
the caps and bases are in line when tightened
down. A sharp tap with a hammer on the end of
the rocker will help to ensure this. See that the
valve stem caps are in place.
After the engine has been run long enough to
get thoroughly hot, the tightness of the nuts
should be rechecked.
It will be found convenient for this purpose
to use a small auxiliary petrol tank while the
engine is being warmed up on the stand, because
all the cylinder head nuts are not accessible with
the proper tank in position.
See that the rocker box gaskets are intact and
replace the rocker box covers.
After tightening the cylinder head nuts with
the engine hot, recheck the tappet clearance at
some convenient time when the engine is cold.
"500 Bullet," 1959 onwards
Remove the cylinder head steady bar, exhaust
pipe, carburettor, plug lead and the decompressor
cable at the handlebar end. Disconnect the rocker
oil feed pipes. Unscrew the five long nuts on the
top of the head, the nut adjacent to the sparking
plug and the sleeve nut by the decompressor.
Withdraw the five studs from the crankcase the
have squared ends to take a spanner.
Remove the rocker covers, rockers and push
rods. The rockers are removed by undoing the
nuts at either end; one of these nuts is bored and
tapped to take the oil union. Slide out the
spindle, taking care that the spring washer at the
push rod end and the plain washer at the other
end do not fall down the push rod tunnel.
Withdraw the push rods and lift the head.
For replacement reverse the order of the
above instructions. Make the joint between
cylinder head and barrel carefully as described in
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