Forklift Engines
Forklifts are classified as small-engine vehicles, the same class in which lawnmowers are classed. The engines of the forklifts all follow the principles of internal combustion. Various forklift brand names and models would have varying engine layout and design. Forklifts are made more toward generating high torque rather than for speed. They generally are geared to low speeds. The engine powers the forklift's drive wheels. The engine is also required to lift and lower the forks through a series of chain pulleys. Nearly all modern forklift engines are fueled by propane as they would be used indoors, where gasoline and diesel engines would be inappropriate because of the exhaust they create.
A four-cylinder engine-block is normally found in a lift truck. Much similar to the engine in small automobiles, the engines of the forklift have cylinders that contain pistons connecting to a camshaft. The head of every cylinder consists of an intake hatch, an exhaust hatch and a spark plug, each of them spring-loaded and one-way.
Engine Function
Once the operator starts up the forklift engine, propane passes through the opened throttle-plate in a fine spray and mixes with air that comes from the mass air intake before moving into the head intake hatches of the cylinder. Every one of the four pistons is staggered to rise in a precise sequence, compressing the air and propane mixture as each piston rises to the top of the head. With extremely precise timing, the battery and alternator of the engine produce an electrical current which passes through the spark plug. The fuel ignites causing an explosion that drives the piston back down to the bottom of the cylinder, resulting in a continuous turning of the camshaft. In the cylinder, an air pressure imbalance causes the the exhaust hatch to draw out exhaust as more fuel passes into the cylinder. Propane burns much cleaner than gasoline and diesel and the exhaust is not as harmful.