Question 2
(a) Sketch a mechanical fuel pump and label four of its parts.
(b) List five parts of the fuel system for a spark ignition engine.
(c) State three functions of a carburettor.
Observation
Most of the candidates who attempted this question could not provide the required responses to part (a) and (c) of the question. The required responses to these parts are as follows:
(a)
(c) Functions of the carburettor include:
- to prepare a suitable mixture of air and petrol to suit all load and speed
of the engine.
- to regulate the ratio of air and fuel.
- to atomise the liquid petrol.
- to regulate the engine speed.
- to regulate the amount of fuel entering the engine.
- to convert liquid petrol into vapour.
- to enable the engine to run at idling speed.