Page 214 - Mechanic Diesel - TT

MECHANIC DIESEL - CITS

8 The minimum cranking speed of the engine at the starting limit temperature.

Objective of Starting System: To make the engine functional, it needs to be started. Various mechanisms of
the engine become active only after starting, due to which it is possible to use these engines as per requirement.
Starting system is used to fulfill this purpose. There are different types of engines, hence different methods are
used to start them. It is important for people who use engines in any form to know all the methods of starting the
engine. Among these methods, self-starter method is most popular
Construction and Working: The starting system is a combination of mechanical and electrical parts that work
together to start the engine. The starting system is designed to change the electrical energy, which is being
supplied by the battery, into mechanical energy. For this conversion to be accomplished, a starter or cranking
motor is used. A starting system consists of starting motor, magnetic switch, safety switch, battery, cables and
ignition switch. These components are connected with each other through two circuits. One is starting circuit, in
which high current flows which is used to start the engine. Second is control circuit, in which low current flows.

The ignition switch acts as switch for starting circuits also. In starting circuit, the current flows from battery to
starter motor through solenoid or magnetic switch. The control circuit connects magnetic switch with, battery
through ignition switch (Figure 6).

Major components of Starting system

Component of Starting System: Those components of the starting system, which enable the system to function
properly, are called components of the starting system. Knowledge of these components is essential to fully
understand the starting system. The arrangement of components of the starting system is shown in the figure

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CITS : Automotive - Mechanic Diesel - Lesson 62 - 66