Engine Turnover
Engine turnover refers to the rotation of the crankshaft and other engine components without the engine actually starting. This is typically accomplished by the starter motor, which engages with the flywheel and turns it over. Engine turnover is necessary to build up the necessary compression in the cylinders before the engine can start.
Engine Start
Engine start occurs when the engine's fuel and ignition systems are activated, causing the engine to begin running on its own power. This is in contrast to engine turnover, which is simply the rotation of the engine's components without it actually running.
In more detail, here are the steps involved in engine turnover and starting:
Engine Turnover
1. The starter motor engages with the flywheel and begins to turn the crankshaft.
2. As the crankshaft rotates, it turns the pistons and other engine components.
3. The valves in the engine's head open and close, allowing air and fuel to enter the cylinders and exhaust gases to escape.
4. The compression stroke compresses the air and fuel mixture in the cylinders.
Engine Start
1. When the compression stroke reaches its peak, the spark plug ignites the air and fuel mixture.
2. The combustion of the air and fuel mixture creates a rapid expansion of gases in the cylinders.
3. This expansion forces the pistons downward, which in turn turns the crankshaft.
4. The engine continues to run as the starter motor disengages and the engine's own power keeps it running.
In summary, engine turnover is the rotation of the engine's components without it actually running, while engine start is the process by which the engine begins to run on its own power.
