In-Depth Project: Starter Motor Components, Disassembly & Assembly

This project provides an overview of starter motors, detailing their function in initiating the combustion process in an engine. It outlines the various components of a starter motor, including the solenoid, armature, commutator, brushes, plunger, lever fork, pinion, and housing, explaining the role of each part. The project also provides a step-by-step guide on disassembling and assembling a starter motor, including necessary tools and precautions. It emphasizes the importance of starter motors in modern vehicles, highlighting their role as the engine's switch and referencing alternative starting methods used before their invention. The document concludes with a list of references used in the project. Desklib offers a variety of study tools and solved assignments for students.

PROJECT ON STARTER MOTOR
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TASK 3
Starter Motor
Introduction
A starter motor refers to a device that allows the combustion process in
an engine to take place by ensuring that the required amount of
mechanical energy is available or rotating the crankshaft. They can be
either hydraulic, pneumatic or even electric.
A hydraulic motor can be described as a mechanical actuator that is used
in conversion of hydraulic flow and pressure and turn it into torque and
rotation.
The pneumatic motor is a kind of motor that expands compressed air in
order to do mechanical work (Deanna, 2008). They generally use linear
motion from a piston actuator in order to convert the energy from the air
that is compressed and use it for mechanical work.
The electric motor is an electrical device that is used in converting
mechanical energy from electrical energy. Such motors work by producing
force using the winding currents and motor’s magnetic field using power
from the alternating current or direct current.
This project will try to look at a starter motor in detail.
Components of a starter motor
The solenoid is usually a wire that is coiled in order to act as an
electromagnet. It uses an electric current to produce a magnetic field and
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finally cause linear motion. The main use of a solenoid is to power the
starter of a motor vehicle.
The armature is a laminated soft iron core that is enclosed with a lot of
conductor windings. It is usually electromagnetic and mounted to act as
support for the bearings and drive shafts.
The commutator is a portion of the shaft that is located at the back
of the housing and are where the brushes run thereby conducting electric
current. It comprises of two plates that to the armature axle. The two
plates act as connections for the electromagnet.
Diagram of a starter motor
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The brushes usually run on a section of the commutator that is
located at the back part of the housing, thereby conducting electric
current by allowing contact with the commutator.
The plunger does its work by using the connection of the solenoid
and car battery in thereby allowing the plunger to move forward, thus
engaging the pinion.
The lever fork is activated by the motion of the plunger thereby activating
the pinion.
The pinion comprises of a special collection of springs and gears.
When the starter engages, then the gear extends inside the housing of
the gearbox and then engaging the flywheel. This allows for the
combustion procedure to start by spinning the engine.
The housing uses screws to hold the starter fields. They usually
comprise of a range of two to four field coils that are connected in a range
of series. The field coils are converted into electromagnets by using the
energy from the battery thereby turning the armature and finally creating
a magnetic field.
Tools needed
 Socket set
 Set of spanners
 Soldering torch
 Screwdrivers
 Pliers or side cutters
 Hammer
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 Oil
 Rags
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Steps in disassembling the starter motor
In order to remove the starter from the vehicle, first disconnect the
battery since you could end up hurting yourself due to the high current
cables involved. Secondly, take out the sensor cable, cooling fan and
clutch cylinder. Continue by removing the bolts of the starter in order to
take it out from the vehicle. Use a rag that is soaked in petrol to clean the
starter (Robert, 2003). Ensure to mark the solenoid and case in order to
avoid confusion when assembling the parts.
Unscrew the two screws that usually holds the cover at the back and keep
the brushes intact. Take out the clip and the spring. Next take out the
heat cover (heat shield). Unplug the motor cable from the solenoid. After
this, take out the long bolts that holds together the motor. Take out the
brush cover. Keenly check for 2 brushes that are connected to the field
windings and unclip them allowing you some space to remove the brush
by pulling the spring backwards. Carefully take out the brush holder and
field windings. The disassembly step is finished by unbolting the solenoid
in order to take out the solenoid and armature at a go.
Steps in assembling the starter motor
Assembling the starter motor is much easy than disassembling.
Firstly, put the brushes leaving them mid hanging outside and leave the
spring in a jammed position against the brush side. This makes the
assembly work easy as the spring won’t give you a hard time. The
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solenoid and armature usually go in at a go by make sure you place them
on the fork in at the required place. Take the brush plate and fit it. Insert
the bushes inside the brush holders. Check if the bolts are on the same
line and then properly push in the brushes.
Afterwards, the brush cover or back plate are to be inserted and held into
position by the long bolts. Place a single screw in the brush holder after
ensuring that all things are in line and then tighten it. Ensure that the
armature is able to turn in a free manner. Place the spring and clip and on
the shaft add a little amount of oil. Finally, add some oil also on the
starter’s nose and then fit the end cap.
Conclusion
Starter motors are an effective tool in making work easy as even though
man is very capable but his capabilities are limited and can’t perform
some duties without some devices. Before man found out that starter
motors exist, some common ways were used in starting engine. They
included some crazy yet effective methods like removable cranks handles,
and gun powder springs. It might seem to be a smart part of the whole
car, but if you take it out then the car won’t even start let alone move. In
simple language, the starter is the switch of the engine. Ask yourself, can
bulbs turn on and off without the wall switch?
References
Clinton, J. (2011). Manual of Repairing & Reconditioning Starter Motors
and Alternators. New York: Swordworks.
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Deanna, S. (2008). Auto Repair for Dummies. New York: For Dummies.
Robert, B. (2003). Alternators and Starter Motors. New York: NYU Press.
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