Rolls-Royce Corniche - Brushgear and Heatsinks; Brushgear-To Inspect

- - --- -
Workshop Manual
Rolls-Royce Silver Shadow 8 Bentley T Series
Chapter M
Alternator-TO dismantle
7. close up the retaining tongue at thtl base of
(see Figs M 33 and M34)
each firld terminal blade and withdraw the brush
spring and
terniinal assemblies froni the moulded
1. Remove the shaft nut. spring washer, pulley biushbox.
and fan from the drive-end of the alternator.
2.
Unscrew and remove the three ' through' bolts.
3.
Mark the drive-end bracket, lamination pack
and slip ring cover so that they can be assembled in
correct angular relationship to each other.
4. Withdraw the drive-end bracket and rotor from
the stator. The drive-end bracket and rotor need not
be separated unless it is necessary to examine the
drive-end bearing or to renew the rotor.
In this event, the rotor should be removed from
the drive-end bracket by means of a hand press,
having first removed the shaft key and bearing
collar.
5.
Remoke the terminal nuts, washers, insulating
pieces,
brushbox screws and the 2B.A. hexagon-
headed bolt from the slip ring end bracket. Retain
the two washers fitted between the
blushbox
moulding and the end bracket.
6. Withdraw the statdr and heat sink assemblies
from the slip ring end bracket.
B rushgear-To inspect
1.
Measure the brush length.
A new brush is
I5,YO mm. (0.625 in.) long, a fully worn brush is
4,00 mm. (0.156 in.) long, and must be renewed at
or near this length. The new brush is supplied
complete with brush spring and
' I,ucarl terminal
blade and has merely to be pushed in until the
tongue registers. To ensure that the terminal is
properly retained, carefully lever up the retaining
tongue with a screwdriver blade, so that the tongue
makes an angle of
30°with the terminal blade.
2.
The nominal brush spring pressures are
between 113 g. and 142 g.
(4 oz and 5 oz) with the
spring compressed to
19,84 mm. (0.781 in.) in
length and 212 g. to 242 g. (7.5 oz to 8.5 oz) with
the spring compressed to
10,40 mm. (0.lOfi in.) in
length. These pressures should be measured if
equipment is available.
FIG. M33 BRUSHGEAR AND HEATSINKS
1 Stator
4 Warning lamp 'AL' 8 Output terminal
2 Star point
5 Through bolt 9 Terminal blade
3 Negative heat sink and
6 Slip ring end cover retaining tongue
anode base diodes
7 Terminal 'AL' 10 Slip ring brush
(black)
11 Positive heat sink
end cathode base
diodes