​QUESTIONS AND ANSWERS ABOUT PETROL ENGINE.

  • What is meant by internal combustion?

The fuel is burnt inside the engine’s cylinder.

  • Name the four strokes of the Otto cycle.

Induction stroke

Compression stroke

Power stroke and

Exhaust stroke.

  • How can you identify the inlet valve from the exhaust valve on a particular engine?

The inlet valve/valves has a larger head than exhaust.
What is the speed of the camshaft compared with that that of the crankshaft?


  • What is meant by the term Valve overlap?

Both valves open together.


  • What is meant by the Swept volume of an engine?

It is the volume of a cylinder between Top dead center  (T.D.C)  and Bottom dead center  (B.D.C), multiplied by the number of cylinder.

  1. What determines the stroke of an engine?

It is twice the crank radius.

  • Why must there nomally be a clearance between the end of a valve and its operating mechanism?

To allow for expansion of the valve due to heat.


  • What is most common method of driving the camshaft on modern light vehicle engine?

A toothed belt


  • Why are multiple cylinders used instead of a single large cylinder?

Uneven torque, a large flywheel and heavy weight make the single cylinder engine unsuitable.

  • State the major operating difference between two-stroke engines.

The operating cycle takes one revolution of the crankshaft on a two-stroke and two revolution on a four-stroke.

  • Give the meaning of the term of crankcase compression.

It is one method of compressing the fresh charge of mixture on a two-stroke engine before transferring it to the cylinder.


  • What is the probable cause of bubbles in the coolant when carrying out a cylinder leakage test?

Cylinder head gasket allowing leakage into the cooling system.

B.W.C



      END

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s