Power
There are numerous types of forklifts which are powered by propane gas. Propane-powered forklifts are simple to refill. The gas is stored in a pressurized tank on the truck's rear. The propane is pushed into the engine, where it is converted into vapor and then the vapor combines with air. The forklift throttle is utilized to control the flow of vapor. A spark plug fires up the air and vapor mixture producing pressure which makes the pistons move. The pistons turn the wheels and power the hydraulic pump.
As the types of forklifts that are operated by propane have low emissions and are clean burning, they are best to be used inside other buildings and warehouses.
Hydraulics
What allows a forklift to raise and transport heavy stuff from one place to another is the hydraulic system. Cylinders, a pump and tubes make up the hydraulic system. The pump forces dense fluid through the tubing and into the cylinders. The build up of pressure pushes a piston, which raises the forks. When the operator lowers the forks, the hydraulic fluid flows out of the cylinders and back in the pump.
Steering
Propane forklifts work well where maneuverability is necessary. Unlike an automobile, a forklift makes use of its back wheels to pivot, that allows the forklift to rapidly pivot on a tight radius.