Page 130 - Mechanic Diesel - TT

MECHANIC DIESEL - CITS

• Fuel injector: The function of the fuel injector is to deliver finely atomized fuel under high pressure to the
combustion chamber for the engine.

Diesel fuel tank, fuel feed pump and electrical pump.
Fuel Tank

The Fuel tank is provided for storing diesel required for running the engine. It is constructed of either pressed
sheet metal with welded seams and special coating to prevent corrosion or fiber glass reinforced plastic materials.
It may be round or rectangular in shape. It is mounted above the engine assembly.
Parts of the fuel tank
• Filler neck and cap
• Baffle
• Fuel gauge sensing unit (Float)

• Filter
• Sediment bowl and drain plug
Filler neck is provided for pumping diesel into the fuel tank. A cap is provided for closing the tank tightly. A vent
hole Is provided either in filler neck or in cap to maintain Atmospheric pressure in the tank above the fuel. Baffles
are provided in the fuel tank to minimize the Slushing of fuel due to movement inside the tank. Fuel gauge sensing
unit is provided to know the level of fuel Available in tank. It consists of a float resting on the surface of the diesel
in the tank. The float with the help of the Electrical sensing system indicates the level of the fuel Available in the
tank, on the dash board fuel-gauge. Filter is provided at the lower end of the suction pipe. It Filters heavy foreign
particles. At the bottom of the fuel tank a drain plug is provided to Collect sediments and drain it out of the tank.
Function: A feed pump is usually mounted on the F.I.P. and is driven by the camshaft of F.I.P. It sucks fuel from
fuel tank and supplies it to fuel filters.
Construction
The fuel feed pump consists of a barrel, a plunger, a plunger return spring, spindle, roller tappet, suction and
delivery valves, hand primer and pre-filter.

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CITS : Automotive - Mechanic Diesel - Lesson 31 - 38 CITS : Automotive - Mechanic Diesel - Lesson 31 - 38