Royal Enfield 350 BULLET 1949 Workshop Maintenance Manual Download

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ROYAL ENFIELD WORKSHOP MANUAL

(iii) Start the engine and set to run at normal

idling speed.

(iv) Connect the negative lead of a moving coil

voltmeter,  calibrated  0-10  volts,  to  one  of  the
dynamo terminals and connect the positive lead to a
good  earthing  point  on  the  dynamo  yoke  or  engine.
Reverse  voltmeter  connections  on  negative  earth
machines.

(v) Gradually increase the engine speed, when

the voltmeter reading should rise rapidly and without
fluctuation.  Do  not  allow  the  voltmeter  reading  to
rise above 10 volts and do not race the engine in an
attempt to increase the voltage. It is sufficient to run
the dynamo  up to a speed of 1,000 r.p.m. If there is
no reading, check the brush gear, as described in (vi)
below. If there is a low reading of approximately 1/2
volt,  the  field  winding  may  be  at  fault,  see
Subsection  4(d).  If  there  is  a  reading  of
approximately 1.1/2 to 2 volts, the armature winding
may be at fault, see Subsection 4 (e).

(vi) Remove the cover band and examine the

brushes  and  commutator.  Hold  back  each  of  the
brush  springs  and  move  the  brush  by  pulling  gently
on  its  flexible  connector.  If  the  movement  is
sluggish,  remove  the  brush  from  its  holder  and  ease
the  sides  by  lightly  polishing  on  a  smooth  file.
Always replace brushes in their original positions. If
the brushes are worn so that they do not bear on the
commutator or if the brush flexible is exposed on the
running face, new brushes must be fitted.

Test the brush spring tension with a spring scale

(see Fig. 2). The correct tension is 16 - 20 oz. and
new springs must be fitted if the tension is low.

If the commutator is blackened or dirty, clean it

by holding a petrol-moistened cloth against it while
the engine is turned slowly by means of the kick
start, with sparking plug(s) removed.

Re-test the dynamo as in (v) above. If there is still

no reading on the voltmeter there is an internal fault
and the complete unit should be replaced if a spare is
available. Otherwise the unit must be dismantled, see
Subsection 4 (b) for internal examination.

(vii) If the dynamo is in good order, restore the

original connections. Connect regulator unit terminal
"D" to dynamo terminal "D" and regulator terminal
"F" to dynamo terminal "F" and check the regulator.

4 (b). To Dismantle

Remove the dynamo from the motor cycle. To

detach the dynamo from the Magdyno, unscrew the
hexagon headed nut from the driving end cover and
slacken the screws securing the band clip.

To  dismantle  the  dynamo  proceed  as  follows:  Bend
back the tag on the washer "B" locking the screw "A"
(see  Fig.  1).  Remove  this  screw,  withdraw  the  gear
"C"  from  the  shaft  with  the  aid  of  an  extractor  and
remove the key(s) "D" from the shaft.

(ii) Remove the cover band "H," hold back the

brush springs and lift the brushes from their holders.

(iii) Take out the screw "J" with spring washer

from  the  centre  of  the  black  moulded  end  cap  "G."
Draw  the  cap  away  from  the  end  bracket,  take  off
terminal  nut  "F"  and  spring  washer,  and  lift  the
connections off the terminals.

(iv) Unscrew and remove from the drive end

bracket the two through bolts "L"securing the drive
end bracket "N" and commutator end bracket "Q" to

the yoke "M." Hold the nuts “K” at the commutator

Section G2b Page 2

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