Post by sangrelx on Oct 17, 2012 0:06:05 GMT -5
Ok for those who are curious or want a better understanding of what is going on in your little 4 stroke engines and how valves work etc.. Here is a quick and easy description of how a 4 stroke motor works.
4 Stroke is easy to understand if you consider them as Stages or Steps.
Intake, Compression, Power/Combustion, Exhaust.
Stage 1 Intake
the initial pull back of the piston brings in fresh air and fuel.
The intake valve opens to allow this mixture of air and fuel into the engine. It works like a vacuum sucking air/fuel in through one valve.
Air is pulled in through the air intake and it passes through the carburetor. This is also where the A/F screw comes into play. This adjusts the ratio of Air to Fuel coming into the engine.
Once this air and fuel mixture enters the engine. The intake valve will close.
Stage 2 Compression
The piston begins compressing the air and fuel by moving upwards towards the head.
During this motion upwards right as the piston gets to TDC (Top Dead Center) the spark plug fires igniting this compressed mixture of air and fuel.
Stage 3 Power/Combustion
The power from this fuel igniting and the expansion of the exhaust gasses pushes the piston back down.
Stage 4 Exhaust
When the piston starts to travel upwards again the exhaust valve will open and allow the exhaust/burned fuel to escape via the exhaust pipe.
Then the exhaust valve closes and the intake valve opens right behind it to begin the same cycle again.
That is in my own words the simplest explanation of a 4 stroke engine.
So just remember how these motors work during your next valve adjustment or carb adjustment.
hope this is helpful to some of you guys.
4 Stroke is easy to understand if you consider them as Stages or Steps.
Intake, Compression, Power/Combustion, Exhaust.
Stage 1 Intake
the initial pull back of the piston brings in fresh air and fuel.
The intake valve opens to allow this mixture of air and fuel into the engine. It works like a vacuum sucking air/fuel in through one valve.
Air is pulled in through the air intake and it passes through the carburetor. This is also where the A/F screw comes into play. This adjusts the ratio of Air to Fuel coming into the engine.
Once this air and fuel mixture enters the engine. The intake valve will close.
Stage 2 Compression
The piston begins compressing the air and fuel by moving upwards towards the head.
During this motion upwards right as the piston gets to TDC (Top Dead Center) the spark plug fires igniting this compressed mixture of air and fuel.
Stage 3 Power/Combustion
The power from this fuel igniting and the expansion of the exhaust gasses pushes the piston back down.
Stage 4 Exhaust
When the piston starts to travel upwards again the exhaust valve will open and allow the exhaust/burned fuel to escape via the exhaust pipe.
Then the exhaust valve closes and the intake valve opens right behind it to begin the same cycle again.
That is in my own words the simplest explanation of a 4 stroke engine.
So just remember how these motors work during your next valve adjustment or carb adjustment.
hope this is helpful to some of you guys.