Engines

The vehicle's engine can be either a gasoline or diesel engine. The engine in trucks and buses is in most cases a 4-stroke diesel engine with 6, 8 or more cylinders.

Engine with 4 cylinders.

The 4-stroke engine:

In principle, the 4-stroke engine works in such a way that a piston in each cylinder of the engine is set in motion when a mixture of air and fuel is ignited.

The movement takes place in four beats:
1. intake
2. Compression
3. Combustion
4. exhaust

1. Takt.
2. Bar.
3. Bar.
4. Bar.

Diesel engines

In a diesel engine, air is sucked into the cylinder and fuel is injected into the cylinders under high pressure through nozzles. In front of the air intake is an air filter to retain impurities in the air. In front of the fuel pump is a fuel filter to retain impurities in the fuel. These filters must be replaced periodically.

In a diesel engine, combustion occurs by spontaneous combustion due to the high pressure in the cylinder (compression). Auto-ignition requires high temperature/pressure. Therefore, when starting the engine, the air in the cylinders must often be heated.

This is often done using a glow plug that is powered by operating a switch on the instrument panel or by using the ignition key.

1. clutch.
2. Gearbox.
3. Cardan shaft.
4. Support bearing.
5. Drive shaft.
6. Differential.
7. Differential lock.
8. Rear eye.
9. Hub reduction.

Diesel engine.
Fuel pump.
Fuel filter.
Speed limiter.
Nozzle pipe.

Operating errors:

• If the preheater is not used or is used too briefly, a cold diesel engine may not start or may start only with difficulty.

• If the wrong fuel is selected during the winter period, there is a risk of engine failure due to clogging (paraffin formation) in the fuel filter or in the fuel line between tank and engine.

1. fuel filter.
2. Bleed screw.
3. filler screw.
4. breather screw.
5. Hand pump.
6. Fuel tank.

Checking the engine:

• It is important that the engine is filled with sufficient lubricating oil. The oil level must be between the minimum and maximum marks on the dipstick (check light if necessary).
• The cooling system must be sufficiently filled according to the instructions in the manual.
• For cars that include hydraulics for the clutch, check the system for sufficient fluid.
• The exhaust system must be tight and have sufficient silencing effect, as judged by abnormal exhaust sound.

Signs of engine failure:

• Unnecessary smoke from the engine exhaust can indicate a worn engine or fuel system failure.
• If there is an abnormal amount of noise when accelerating, this indicates a fault in the exhaust system (breakage or corrosion).

Speed limiter:

• Newer trucks must be equipped with a speed limiter set so that the speed cannot exceed 90 km/h.
• Newer buses must be equipped with a speed limiter set to a maximum of 100 km/h.

Lubrication

• Lubrication, antifreeze and maintenance are carried out according to the vehicle manufacturer's instructions. See instruction manual.

Coupling

1. The motor is connected.
2. The motor is disconnected.

The main function of the clutch is to engage and disengage the connection between the engine and gearbox at standstill and when changing gear. The clutch must be able to transfer the full traction of the engine without slipping when engaging.

The clutch is usually activated by pedal pressure, which is often transferred to the clutch by hydraulics and possibly compressed air. This means that it can be very difficult to activate the clutch without compressed air on the vehicle's compressed air system.

Signs of a fault:
If the engine revs increase when accelerating without the vehicle speed increasing, this indicates a fault in the clutch, i.e. the clutch is "slipping".

Operating errors:
Operating the coupling too slowly at the coupling point causes extra wear and risk of damaging the coupling.

(Gear selection is difficult to listen to due to the design and location of the engine. You should therefore follow the instructions in the car's owner's manual).

If the gear change is difficult with a loud noise, it may indicate incorrect operation or a fault in the gearbox or clutch.

In order to make the necessary adjustments to speed and traction, the car must be equipped with a gearbox, which contains a number of gear sets that can be used in different combinations. Most large cars have five or more gears for forward driving and one gear for reverse driving. On larger cars there is a switch between "High" and "Low" gears, which allows for greater choice of the appropriate gear. To operate such a gear, follow the instructions in the car's owner's manual. For certain types of driving, fully automatic gearboxes are used.

Operating errors:
Driving in the wrong gear, which overloads and damages the engine, can cause unnecessary smoke.

1. Differential (rear eye)
2. Rear axle.

Differentials

The differential is basically a gear mechanism inserted between the axles of the car's driving wheels. The differential is connected to the gearbox through a cardan shaft and is designed so that the engine's traction is distributed equally to both rear wheels while allowing the rear wheels to rotate at different speeds, which is necessary during cornering.

Differential lock

With a differential lock, the effect of the differential can be canceled so that the rear wheels can only rotate at the same speed. This prevents wheel spin when the rear wheels have different grip, for example in slippery or greasy conditions. The differential lock can be engaged and disengaged using a switch on the instrument panel, either when the car is stationary or when driving straight ahead with both rear wheels having equal grip and rotating at the same speed.

ASR (Anti Spin Regulation)

ASR prevents the drive wheels from spinning (spinning), e.g. on a slippery road surface, when exiting snow-covered parking lots, or when driving in curves. ASR regulates to achieve optimal propulsion. A warning light warns the driver if the ASR system is in operation.

Energy and environmentally friendly driving

To avoid air and noise pollution, the engine should not be left idling for long periods of time. The engine should only be started just before driving or for the short time necessary to achieve sufficient working pressure in the braking system. Driving style also has a major impact on fuel consumption. High speeds and aggressive driving with heavy acceleration when overtaking, for example, significantly increase fuel consumption, while proper driving technique can save up to 10% fuel. Energy-efficient driving means generally avoiding unnecessary and frequent speed changes.

When approaching light-controlled intersections, you should anticipate whether it will be necessary to stop and, if so, adjust your speed for the final stretch towards the intersection, rather than continuing at high speed and then braking hard at the end.

Other legal regulations on eco-driving

The vehicle must be operated in such a way that it does not make unnecessary noise or produce unnecessary smoke and gases.
Unnecessary and disruptive driving must not take place near buildings. If driving is necessary, the driver must drive in such a way that others are disturbed as little as possible.
Possible prohibitions against idling.
When reducing speed, fuel consumption can be reduced by fully releasing the accelerator and applying the engine brake (engine braking) rather than decelerating.