Royal Enfield CO, Руководство по техническому обслуживанию мастерской

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ROYAL ENFIELD 350cc O.H.V. WORKSHOP MANUAL
Page 31
Observe that the cam is fitted with its flat side
towards the armature of the machine.
The contact breaker end shield can now be
removed if the fixing screws, pillar and spring and
earthing terminal nut are unscrewed.
Take out armature by tapping with a soft drift
from the drive end.
Care should be taken not to allow the yoke to
come in close contact with any iron filings as the
magnets which are die-cast within the body will
attract these, and cause the armature to bind.
65. Test and Repair of Magneto.
When the armature has been removed it should
be examined for actual structural faults, such as
cracked or bent shafts. Any flaw in the winding needs
special equipment to detect.* In the absence of this
some idea of the condition can be obtained with the
aid of a battery.
Screw the contact breaker retaining screw into
the end of the armature shaft. Connect one pole of a
2-volt cell to this with an ammeter in series. Connect
the other pole of the battery to the core of the
armature. The ammeter will then record the current
taken
by the primary turns-this should be
approximately 3 amperes. To check the secondary
winding, connect a piece of H.T. cable to the brass
insert of the slipring and hold the other end a little
away from the armature core. If the lead from the
battery which was connected to the core is then
flashed quickly on and off the core, a high tension
spark should occur between the H.T. cable and the
core.
No spark between these points indicates that there
is a fault either in the armature windings or the
condenser and a replacement should be fitted.
TOOL FOR REMOVING ARMATURE BEARING
Fig. 47
It is important that the two ball bearings which
support the armature are in good condition. If they are
packed on assembly with a grease such as a suitable
high-melting point grease they will stand an almost
unlimited amount of normal wear, but if they start to
fail due to a bent shaft or other cause they must be
replaced. They can be removed with a tool as shown
in Fig. 47, and they should be replaced with a
pressure of 250 lbs. At the works this is done in a
* i.e., an ohmmeter. The resistance of the secondary winding
measured between the slip ring and earth should be approximately
4,000 ohms. If the resistance is considerably greater or less than
this figure, the secondary winding may be considered to be faulty.
hydraulic press, but in case of emergency they can be
driven in with a mandrel made to the dimensions
shown in Fig. 48. The serrated fibre washer fits
behind the race to prevent any electric current
attacking the surface of the bearings.
MANDREL FOR REPLACING ARMATURE BEARINGS
Fig. 48
66. Reassembly of Magneto.
Thoroughly wash out cages and balls and dry.
Re-pack with high melting point grease. Refit
armature and contact breaker end plate, taking care
that the distance shims are in position. Check
armature for endplay. Armature should revolve easily
when turned by hand, with not more than .003 in.
endplay.
CONTACT BREAKER BODY AND TAPPET
Fig. 49
Adjust by adding or leaving off shims under
contact breaker end plate until correct.
Fit cam in position with Bowden control plunger in
its correct slot and secure with circlip. See Fig. 50.
CONTACT BREAKER END PLATE
Fig. 50
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