Ignition and starting systems

Question 1

What is a magneto

Answer 1

Self-contained AC generator driven by the engine for purpose of ignition in a reciprocating engine

Question 2

Why are magneto ignition systems preferred over battery type ignition systems for reciprocating engines

Answer 2

Magnetos are independent ignition sources and do not rely on battery powered to provide ignition

Question 3

What can cause a reciprocating engine to continue to run when the nation switch is in the off position

Answer 3

Break in the P lead wire

Question 4

What is the purpose of the condenser in a high tension magneto electrical system

Answer 4

To prevent arcing at points and to hasten the collapse of the magnetic field around the primary coil

Question 5

Where is E gap position

Answer 5

When the polls of the rotating magnet or a few degrees pass the neutral position. He gap is the position at which the points begin to open

Question 6

What are the three major circuits of a high tension magneto system

Answer 6

Magnetic circuit, primary electrical circuit, secondary electrical circuit

Question 7

What are the components of a high tension magnetic circuit

Answer 7

Magnetic circuit consist of a permanent rotating magnet, soft iron core, Pole shoes

Question 8

What happens when the primary breaker points open in a magneto

Answer 8

Stop the flow of current in the primary coil

The magnetic field that was omitted by the primary coil collapse. As this magnetic field collapses, the flex line that cut across the windings of the secondary coil induce a pulse of high-voltage current in the secondary coil needed to fire the spark plug plug

Question 9

What is the Piston position when the spark occurs in a cylinder

Answer 9

The piston is a specified number Of degrees Before top dead center on the compression stroke

Question 10

What is a dual magneto

Answer 10

Incorporates to magnetos in one housing. They share the rotating magnet and cam, However they have their own set of points, coils, and distributor blocks

Question 11

What is the difference between a low tension and high tension ignition system

Answer 11

Hi tension system, the high-voltage is generated in the magneto and flows to the plugs through a high tension lead

Low tension system the low-voltage his generated and the magneto and flows through a low tension lead to the primary winding of a transformer coil located near her each spark plug

Question 12

When you ignition is off what is the condition of the primary circuit

Answer 12

It is completed through the ignition switch to ground

Question 13

What three conditions are required to fire plugs in a cylinder when the piston is in the prescribed position

Answer 13

The magnetos Magnet polls must be in the E gap position, The breaker points must be open in the distributor rotor Must be aligned with a distributor electrode for that cylinder

Question 14

What is a dual ignition system, and what part of the system is grounded when the ignition switch is placed in the right position

Answer 14

A dual ignition system uses to separate magnetos with the harness arranged so that each magneto fires one plug in each cylinder. If the switch is set a right, they left magneto will be grounded preventing it from firing

Question 15

What is internal timing of a magneto

Answer 15

Adjusting the breaker points to open when the polls of the rotating magnet are at E gap position

Question 16

What is the purpose of an impulse coupling used with a magneto

Answer 16

Used to retard the timing of the spark to after top dead center for starting the engine.

it provides a momentarily hi rotational speed to produce a spark at low crankshaft RPM

Question 17

What is staggered ignition timing

Answer 17

It is the firing of one spark plug before the other instead of firing them simultaneously

Question 18

What is the proper spark plug reach

Answer 18

When the electrode End of the plug inside the cylinder is in the best position to achieve ignition

Question 19

Why is it important to keep track of the cylinders that spark plugs are installed in

Answer 19

Spark plugs can provide a lot of information about the health of a specific cylinder

Question 20

What type ignition system is used in most turbine engine’s

Answer 20

Electric capacitor type ignition systems

Question 21

What is the function of the igniter plug in a turbine engine

Answer 21

To provide a discharge gap for the current, which is stored in the capacitor.

They discharge results in a high intensely spark which ignite the fuel air mixture

Question 22

When are turbine engine ignition system is normally in use

Answer 22

Only for starting a restarting an engine

Question 23

What are two types of igniter plugs

Answer 23

Annular rum -Long reach plugs that extend into the combustion chamber

Constrained gap- A short reach plug that does not extend into the chamber because the spark does not remain close to the plug

Question 24

What is the purpose of a dual magneto configuration

Answer 24

For redundancy and safety, in case one magneto fails

Question 25

How can you tell if a starter communtator Is dirty or worn

Answer 25

Excessive noisey starter

Question 26

What does it mean when the starter relay clicks when the starter switch is placed in the start position

Answer 26

The supply voltage is too low to supply enough current to the relay coil to fully engage the contact points

Question 27

What is the advantage of air turban starters, when compared to electric starters, for large turbine engine’s

Answer 27

Light weight, and do not have the same cool down periods As electric starters

Question 28

Why do turban igniters not get carbon filed as often as reciprocating engine spark plugs

Answer 28

Extremely high rates of electrical discharge in the turbine igniter

Question 29

What are the three parts I have an ignition system of a turbine

Answer 29

Exciter, ignition Lead, and igniter