Royal Enfield CONSTELLATION 1958, Руководство по техническому обслуживанию мастерской

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There is, however, a tendency to flood, and for
normal use a conventional float chamber fixed
to the carburetter is more satisfactory.
Main Jet ... ... ... 480
Needle Jet ... ... ... 109
Throttle Valve ... ... No. 5
Needle Clip in third groove from top.
Twin Carburetters (see Section F)
Both carburetters are identical in all respects
but for the float chamber arrangement, which is
as follows
Carburettor type 376/242 supplies the
left-hand cylinder, and has an integral float
chamber which also controls the fuel supply via
a connecting pipe to the right hand instrument
type 376/243. This does not have a float
chamber in unit with it.
Main Jet ........................ ... ... 320
Needle Jet ..................... ... ... 106
Throttle Valve
.......... ... ... 376/4
Pilot Jet ......................... ... ... 25 c.c.
Needle Position .......... ... ... 3
15. Air Filter
Provision is made for housing a 5 in.
diameter Vokes Micre-Vee felt and gauze dry
filter in a compartment of the toolbox, but the
use of this may reduce the maximum speed
slightly.
Owing to the positions of the twin
carburettors in relation to the toolbox, it is not
possible to attach air filters in this instance.
16. Lubrication System
Lubrication is by the Royal Enfield Dry
Sump system which is entirely automatic and
positive in action. The oil tank is integral with
the crankcase, ensuring the full rate of
circulation immediately the engine is started and
rapid heating of the oil in cold weather.
There are two positively driven piston type
oil pumps running at 1/6 engine speed, one at
the rear of the timing cover for pumping oil to
the bearings under pressure and the other at the
front for returning the oil from the crankcase to
the tank. The return pump has a capacity
approximately double that of the feed pump
which ensures that oil does not accumulate in
the crankcase.
The oil from the big ends drains into the
bottom of the crankcase and is prevented by a
baffle from being drawn up by the flywheel.
The oil from the rocker bearings is squirted
through a small hole in the rocker on to the top
end of the push rod. It flows down the push rod
into the cam tunnel where it lubricates the cams
and tappets and thence into the timing chest,
lubricating the timing chains. There are small
holes from the inlet cam tunnel through the
cylinder walls for the purpose of lubricating the
skirts of the pistons and a hole from the inlet cam
tunnel into the timing chest through which
surplus oil from the inlet rockers passes.
The exhaust cam tunnel, however, has no
holes but is kept full of oil to ensure adequate
lubrication of the exhaust cams and prevent
wear. The oil level is maintained to a height in
the groove in the tappet guide where a hole is
drilled into the timing chest, through which
surplus oil from the exhaust rockers passes.
Both pumps are double acting, one side of
the feed pump supplying the big ends only and
the other side the rockers and valve gear. In a
similar manner one side of the return pump
pumps the big end oil back to the tank from the
crankcase and the other side the valve gear oil
back to the tank from the timing chest.
A spring loaded relief valve controls the
pressure of the oil to the valve rocker gear
which is through external pipes.
A gauze strainer is provided for the feed oil
leaving the tank and there is a large capacity felt
filter in the feed to the big ends. An aluminium
cylinder is fitted over the fixing stud inside the
filter element to reduce the volume of oil
required to fill the filter after it has been
dismantled for cleaning and to ensure the rapid
flow of oil to the big ends.
A small circular magnet is also fitted over
the fixing stud inside the oil filter for the
purpose of collecting any ferrous particles
which may be suspended in the oil.
17. Breather
The efficient operation of the breather is of
paramount importance to the performance of the
engine. It acts as a non-return valve between the
crankcase and the outside atmosphere, causing a
partial vacuum in the crankcase and rocker
boxes which prevents the passage of oil into the
cylinders and consequent smoking and oiling of
the plugs.
The breather is located on the driving side of
the crankcase and consists of a small housing
attached to the crankcase by three screws. This
housing contains two pen-steel (or paper) discs
covering two holes drilled into the crankcase.
Accurate seating of the discs is ensured by a
pen-steel plate held between the breather body
and the crankcase.
The Neoprene pipe, found on early models,
which breathes directly into the atmosphere
from the breather housing, has been replaced on
later models by a metal pipe running from the
breather housing to the top of the oil tank.
In addition a breather, in the form of a pen-
steel disc, is situated in a recess in the head of
the special bolt, which secures the alternator
rotor on to the end of the crankshaft. This bolt is
drilled throughout its length, and communicates
Section B11 Page 3
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