Answer: Huge fuel will create improper pressure across the fuel lines and can cause huge amount of Black Smoke.
2. Why is bleeding required?
Answer: The fuel system requires air bleeding under following circumstance:
a.The engine has not been operated for a long time.
b.If a fuel element has been replaced.
c.Engine is started without opening fuel cock & has run for some time.
d.Feed pump is not working properly.
e.If there is some leakage from the Fuel pipes, fuel filter.
3. How to remove AIR LOCK?
Answer: Air lock can be removed by the help of pumping the air primer as procedure given below: a. Loosen the bleeding screw of primary fuel filter. Unscrew priming knob of fuel pump, move it up & down at least 10 to 15 times, till the fuel flows out from air vent screw without air bubbles. b. Tighten the air vent screw after air bleeding. Repeat same steps for secondary fuel filter for air bleeding. c. At last, loosen the air vent screw of fuel injection pump and bleed out air bubbles.
4. What is Thin Film Lubrication?
Answer: Thin Film lubrication is between the Piston rings & the Cylinder Liner; this reduces the metal to metal contact which reduces friction & wear of metal parts.
5. What is the function of Thermostat?
Answer: The thermostat cuts the engine supply if the temperature of the Engine increases or decreases to a certain level.
6. What is the function of Thermostat valve?
Answer: When coolant is at low temperature, the thermostat valve remains closed and coolant flows through bypass passage to water pump (cooling pump). When coolant temperature is over 90 degree C, thermostat fully opens and bypass closes, coolant passes through the radiator.
7. Why should radiator cap not be opened?
Answer: The radiator cap consists of pressure elements, with the help of the radiator cap the pressure of the cooling system remains in operating condition, loosening the radiator cap will cause changes in the cooling system which will be harmful for the DG set.
8. What is over-speeding?
Answer: There are cases when the speed of the engine increases when load is suddenly taken off from the DG, or there is imbalance of load on the DG. This increases the speed of the Engine which will increase the speed of the alternator beyond a safe limit, which would lead to burning of alternator winding.
9. What is the reason for Black Smoke?
Answer: This indicates improper combustion, which could be due to:
a.Choked or wrong air cleaner.
b.Defective fuel injection system.
c.Choked exhaust system or wrong exhaust piping.
d.Engine overload ,Load side electrical short circuit.
10. What is the reason for Blue Smoke?
Answer: Blue smoke is emitted when oil begins to burn in combustion. This could be due to:
a.Excess oil in sump
b.Excesslub oil pressure
c.Worn piston rings & liners
d.Worn valve steam & valve guidese.
11. What is the reason for White Smoke?
Answer: White smoke indicates water presence in combustion chamber. This could be due to:
a.Cracked Cylinder Head
b.Cracked or Damaged Liner
c.Water dilution in diesel burnt or damaged cylinder head gasket.
d.Water presence in combustion chamber which is very dangerous and can lead to a hydraulic lock & extensive damage to engine.
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