Standard Book, Technical General
Piston Engines - Carburettors: DGCA Technical General questions
A float carburettor meters fuel using the pressure drop in a venturi: the faster the air, the more fuel it draws. The mixture control, accelerator pump, priming and idle systems are built around that idea.
Among the 20 questions the themes are air/fuel ratios, rich and weak mixtures and their effects, and starting. Exam sessions have asked 3 of them.
Climbing into thinner air makes the mixture richer, not weaker, so you lean it. A weak mixture can cause backfiring through the induction, while an over-rich one gives black smoke and rough running. Where one is fitted, the accelerator pump squirts fuel when the throttle opens fast, so pumping the throttle before a start can flood the intake and start a fire.
0 answered·5 free questions·0 right
Question 1 of 5
The pressure in the induction manifold of a normally aspirated engine:
Question 2 of 5
Excessive cylinder head temperatures are caused by:
Question 3 of 5
The primary function of a diffuser in a carburettor is to:
Question 4 of 5
A possible cause of the engine backfiring could be:
Question 5 of 5
A fuel strainer should be fitted:
15 more questions in this chapter
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