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4 Stroke Engine

How a 4 stroke engine works:

A four stroke engine has 4 processes it must go through in order for the vehicle to run:

  1. Intake
  2. Combustion
  3. Power
  4. Exhaust

It also requires 4 crucial elements to run:

  1. Air
  2. Fuel
  3. Compression
  4. Spark

4 Stroke engine

Step 1: Intake Stroke

Air and fuel enter the engine through the intake valve between the carburetor and the combustion chamber. Pressure forces the air and fuel into the cylinder as the piston moves downward.

Step 2: Compression Stroke

After the piston moves all the way, the intake valve closes and returns back up the cylinder. The air is being compressed  between the piston and the cylinder head.

Step 3: Power Stroke

When the piston reaches the top of its travel, it is at its prime point to ignite the fuel in order to get maximum power for the vehicle. The ignition coil creates high voltage which the spark plug uses to discharge into the combustion chamber. The spark creates heat which in turn ignites the gases. This process creates rapidly expanding, super heated gases that force the piston back down the cylinder.

Step 4: Exhaust Stroke

When the piston reaches the bottom again, the exhaust valve opens. As the piston travels back up the cylinder it forces the spent combustion gases through the open exhaust valve and out into the exhaust system. When the piston reaches the top again, the exhaust valve closes while the intake valve opens and this 4 step process is repeated over and over again.

4 Stroke

Symptoms of Engine Issues:

  • Poor overall performance
  • Rattling sounds from the clutch
  • Engine tends to stall easily
  • Erratic acceleration
  • Poor fuel economy
  • Misfires and/or backfires
  • Overheating

If you are experiencing any of these issues, bring your car into K-Motion so we can take a look before a minor problem turns into a major problem! The engine is the most important component of your vehicle so it is absolutely vital that you take care of it.


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