Royal Enfield METEOR MINOR STANDARD 1958 Workshop Maintenance Manual page 13

In replacing the heads, see that the dowels are
in position in the cylinder barrels and that the
push rods are the right way up (shallow cups
upwards).
Apply a thin coat of jointing compound to
both sides of the gasket and place it in position.
Lower the cylinder heads over the push rods,
making sure that the rockers locate in the push
rod cups.
Fit the head nuts and washers and partially
tighten down.
When both heads have reached this stage, fit
the induction pipe and tighten the nuts. The
cylinder head nuts can now be finally tightened
down progressively and diagonally from one side
to the other to prevent distortion. After the
engine has been run long enough to get
thoroughly hot, the tightness of the nuts should
be rechecked.
11. Removal of the Valves
Remove the rocker box covers, each held by
four nuts, and swing the rocker clear of the
valve. The hardened steel thimbles or end caps,
fitted to the valves of Standard and early de Luxe
models, must be removed. A tight one may be
removed by means of a screwdriver. Later
deLuxe and all Sports models do not possess
removable end caps.
Using a suitable valve spring compressing
tool, compress the valve springs and remove the
split conical collets from the end of the valve
stem. Slacken back the compressing tool and
release the springs. Withdraw the valve and
place its springs, top spring collar (and bottom
collar if it is loose) and split conical collets
together in order that they may be reassembled
with the valve from which they were removed.
Deal similarly with the other valves in
the heads.
If the valve will not slide easily through the
valve guide, remove any slight burrs on the end
of the valve stem with a carborundum stone. If
Section C13 Page 4
the burrs are not removed and the valve is
forced out, the guide may be damaged.
12. Removal of the Rockers
To remove the rocker, first take off the
cylinder head. Remove the hexagon plug on the
inner side and the rocker spindle may be drawn
out by means of a bolt screwed into the rocker
spindle, which is tapped 5/16 in. B.S.F.
On reassembling make sure that the spring
washers are fitted on the sides of the rockers
nearest the centre of the engine and the plain
thrust washers on the outer sides.
13. Removal of the Valve Guides
To remove the valve guides from the heads
two special tools are required which can easily
be made.
The first is a piece of tube with an internal
bore of not less than 7/8 in.
The second is a mandrel about 4 in. long
made from 9/16 in. diameter bar with the end
turned down to about 5/16 in. diameter for 1/2
in.
Support the cylinder head on the tube which
fits over the collar of the valve guide. Using the
mandrel force the guide out of the head with a
hand press or by using a hammer.
To fit a new guide, support the head at the
correct angle and use a hand press and the same
mandrel. If a hand press is not available and the
guide is replaced by a hammer, use a piece of
tube of 9/16 in. internal diameter to prevent
damage to the bore of the guide. If a valve guide
is removed for any reason, an oversize can be
fitted in order to maintain the interference. It is
necessary to recut the valve seat and grind-in the
valve after a guide has been replaced. (See
Subsection 18.)
A worn exhaust valve guide may give rise to
slight smoking from the exhaust pipe due to oil
passing down the valve stem on to the hot valve
head. This may also be caused or increased by
faulty operation of the breather.
14. Removal of the Sparking Plugs
Care must be taken when removing and
replacing the sparking plugs not to damage the
threads in the cylinder heads.
If the threads do become damaged, they can
be tapped out to a larger size and steel wire
inserts fitted.
Special tools are available for tapping and
inserting the steel wire inserts. The latter tool
consists of a piece of 7/16 in. diameter tube or
rod with a slot cut in the end.
The insert is placed over the tool with the tag
engaging in the slot and it is screwed into the
plug hole in the cylinder head from the outside