Page 188 - Mechanic Diesel - TT

MECHANIC DIESEL - CITS

the bellows to expand and open the valve. When it cools down, the liquid condenses, reducing pressure, and the
valve closes again, stopping the flow of water.

Fan belt
Fan belts are essential in vehicles as they help cool the radiator and circulate coolant throughout the engine. They
connect various components like the water pump, radiator fan, air conditioning unit, and cross the crank pulley.

Fan belts harness the engine’s rotation to power crucial parts such as the water pump, fan, power steering pump,
air conditioning compressor, and alternator. The alternator, which generates electrical power for the car, relies
on fan belts to function. Without them, the alternator wouldn’t charge the battery properly, leading to potential
issues like power steering failure and engine overheating. Fan belts transfer mechanical energy to the alternator,
allowing it to charge the battery and power other electrical systems in the vehicle. Newer cars often use Poly-V
belts to drive multiple engine parts, eliminating the need for separate fan belts. However, older vehicles typically
have separate fan belts, like raw edge cogged belts, specifically for the alternator.
Temperature gauge

The temperature gauge on your dashboard tells you how hot or cold your engine’s coolant is. It’s important
because it shows if your engine is running at the right temperature, too cold, or overheating. Even though it might
not get much attention, it’s crucial to pay attention to it to avoid potential problems with your vehicle.
Temperature sensors
Valeo water temperature sensors help protect your engine and heat exchangers, especially in extreme
temperatures. They measure coolant temperature and send this information to the Engine Control Unit (ECU).
Valeo offers a wide range of these sensors, with 48 different part numbers available. They’re backed by Valeo’s
expertise as a global leader in cooling systems. These sensors enable the control unit to detect engine

175
CITS : Automotive - Mechanic Diesel - Lesson 47 - 56 CITS : Automotive - Mechanic Diesel - Lesson 47 - 56