Page 117 - Vauxhall 20-60 H.P. (R Type) Chassis Shop Manual

VAUXHALL 20-60 SHOP MANUAL

CONTACT POINTS — TO CLEAN

SECTION The surface of these points should have a clean, greyish, frosted appearance;
526 if pined or blackened rub the surfaces of the points against one another,
working the breaker arm up and down. The points should be parted by
hand and allowed to spring back to the fixed points several times, taking
care that the points are not chipped by being allowed to spring back too
hard. Should the points be too bad to clean in this manner, use a smooth
file or a piece of smooth emery cloth, but it is essential that all emery dust
is removed from between the points, after using this method of cleaning.

Oil on the points should be wiped off with a rag soaked in petrol, and do
not replace the distributor cap until the petrol has evaporated. If the points
are badly burned or surrounded by a white or greyish coating, the trouble is
caused by a faulty condenser, or excessive voltage in the charging circuit. It
is possible to run a short distance with a faulty condenser, but it is advisable
to replace this as soon as possible, otherwise considerable difficulty will be
experienced in keeping the points clean, and sparking will be weak.

TO ADJUST

( See Figure 32 )

SECTION The gap between the point in the lever and the stationary point should be
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.
.
527 0 018” (0 45720 mm) to 0 024” (0 60960 mm) when fully open.
If the gap between the points is not within the above limits:–
– Turn the engine over by hand until the rubbing block of the breaker arm
‘A’ is on the lobe of the cam, loosen screw ‘B’ and turn screw ‘C’ until a
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.
0 020” (0 50800 mm) feeler gauge can be inserted between the
points without springing them apart.

– Thoroughly tighten screw ‘B’. Turn engine over again until the rubbing
block of breaker arm ‘D’ is on the lobe of the cam, loosen screw ‘E’
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and turn screw ‘F’ until a 0 020” (0 50800 mm) feeler can be
inserted between the points.
– Thoroughly tighten screw ‘E’.

TO SYNCHRONISE
( See Figure 32 )

SECTION The screws ‘G’, ‘H’ and ‘J’ are provided for convenience in manufacture and
528 to form a method of synchronising the contact points should excessive wear

occur on the rubbing block of one contact arm only, or if for any reason it
has been necessary to replace one arm.
Clearly, if the rubbing block on one breaker arm is ‘higher’ than the other,
there will be a tendency for the ignition timing of three cylinders to be
slightly ahead of the other three, and for the purpose of synchronising,

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