Page 244 - Mechanic Diesel - TT

MECHANIC DIESEL - CITS

One end of the secondary winding is connected to the primary winding and the other end is connected to the HT
of the ignition coil. (High Tension) terminal. Both these windings are immersed in oil in a sealed container, due to
which they are kept cool. Ignition coil is used to convert low voltage into high voltage to produce spark. Its both.
The ends of the winding are connected to the external terminal. The Bakelite cap insulates the secondary terminal
and the primary terminal.

4 Distributor
In multi-cylinder engines, it distributes the high tension current received from the ignition coil to the spark plugs
of all the cylinders according to the firing order. CB installed in it Points also help in creating high tension current
by making and breaking the primary circuit. Apart from this, the ignition timing is also adjusted according to the
engine speed by the advanced retard mechanism associated with it.

Some distributors also have an advanced retard mechanism and a small gear mounted on the shaft to drive the
distributor. The distributor mainly consists of the following parts
Distributor Body

The distributor consists of advanced mechanism, distributor, shaft, bush breaker plate, contact breaker, cam,
condenser, rotor and distributor cap. The bowl shaped distributor housing is closed from the top by a distributor
cap. The cap has segment terminals corresponding to the cylinder number. This terminal high tension as per firing
order
The leads are connected to the spark plug. The center tower of the cap is connected to the HT terminal of the
ignition coil. A spring loaded actuation electrode operates the mercury rotor’s ignition surge. HC current/surge
flows from the rotor arm to the side segments of the distributor cap. The body of the distributor is closed from
above by a cap, due to which the spark plug and HT. (high tension) lead pair.
A shaft is fitted in the middle of the body, it has a cam lobe at the top according to the number of cylinders and a
small gear is fitted at the bottom.

This gear drives the camshaft and drives the distributor. There is a groove cut on the end of the distributor shaft,
in which the oil pump is threaded through the shaft and also drives the pump.

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CITS : Automotive - Mechanic Diesel - Lesson 71 - 75