Horizontal Engine – Advantages and Disadvantages

The cylinders can be arranged in several ways such as vertical, horizontal, inline, V-type, flat or pancake, radial. Single cylinder engines can be arranged in either vertical or horizontal direction as shown in Figure

Merits of horizontal engines:

1. The inertia forces of the reciprocating parts i.e. primary and secondary forces combine together to give an impulse to the chassis frame of the vehicle as the stroke of the engine piston is horizontal. If the cylinder head is towards the front end of the vehicle, then a driving impulse is obtained from the engine. This impulse force slides the engine forward on a smooth floor when the running engine is placed on the floor. Therefore, a vehicle fitted with horizontal engine tends to push forward the moped or the scooter by its impulsive force.

2. Fuel economy is also more.

Demerits of horizontal engines:

1. The crankcase cannot be used for storing lubrication oil for splash lubrication.

2. There will be excessive wear at the lower side of the piston and cylinder liner where the cylinder liner gives support to the engine because the weight of the piston is carried by the cylinder liner.
3. Consumption of lubricating oil is more due to the lubricating oil which dribbles from bearings not returning to the crankcase but it is thrown out by the centrifugal forces.