ELECTRICAL SECTION (SWITCH GEAR AND INSTRUMENTS)
To Dismantle the Board for Cleaning or Replacing Contacts
The complete board should be removed from its faceplate or dash panel and all cables disconnected.
(a) Remove fixing screw "D" and main switch handle "E."
(b) Remove fixing screw "F" and ignition knob "G."
(c) Remove fixing nuts "H" and clamp "J."
(d) Remove fixing nuts, spring washers and plain washers " K."
The terminal base can now be removed from the body. Take care that the
ignition switch parts are not lost, as they will be liable to fall out
when the body is removed.
(f) Examine ignition switch contact pins
and locating sockets "L." Clean with very fine carborundum paper it they
are in a dirty condition. Examine the fixed main contacts "N." They can
be easily removed by unscrewing the one screw "O." If dirty, clean as
above, take care not to bend them out of shape and make sure they make
good contact when replaced. If badly burnt, bent or pitted, replace.
The main rotor contact can be cleaned by first extracting the two
screws "P" from the back. This will allow the removal of the bracket "Q"
from the rotor "R." Take care not to lose the locating steel ball "S."
Clean the contacts if necessary, but replace if badly burnt or corroded.
See that the screws "T" holding the springs are perfectly tight.
If the brass pillars "U" holding the contacts have become loose,
tighten by means of the countersunk screw located in the respective
terminal on the back of the base and accessible after removing cable
(i) Examine the lamp holder plunger "V," clean the tip if
dirty ; a few drops of oil in the socket "W" will ease any stiffness,
but keep it away from the plunger tip. See that the small pressure
prongs in the side lamp holder " X" have not been bent out of place so
that the locating pressure on the lamp is lost.
Re-assembling the Board
the rotor bearing pin with vaseline and locate the rotor in the metal
base bush so that the square is parallel with both the horizontal and
vertical axis of the switchboard when it is in the normal mounting
position and the small contact is across the two fixing spring contacts,
i.e. when the switch is in the maximum "on" position. After coating the
steel ball with vaseline, place it in the locating hole in the stop
plate, that is, on the horizontal centre line. Place the bracket "Q"
over the rotor so that the small hole locates over the steel ball; fix
from the back with two screws "P."
Locate the ignition switch
contact piece "Z" so tliat tlie contact pips bridge across the C+ and B+
sockets, i.e. in an almost vertical position. Place the spiral spring
"AA" over the square portion of the moulded ignition rotor and locate it
in the square of the contact piece "Z" so that the flats of the brass
hexagon on top of the rotor are parallel with the vertical centre line
of the switchboard and the cut-away portion of the moulding points
towards the main switch spindle.Replace the body and switch handles in
the reverse order of the dismantling instructions a, b, c and d.If the
small insulating sleeves "AC" become loose they should be replaced and
held in position with fish glue.On boards fitted with the flat type
clamp, always replace the insulator "AB" before the clamp.