LESSON # 4

Question 1

TWO BASIC TYPES OF FUEL PUMP:

Answer 1

1. PLUNGER-TYPE FUEL PUMP
2. GEAR-TYPE FUEL PUMP

Question 2

The degree of inclination is varied by the movement of a servo piston
that is mechanically linked to the camplate and is biased by springs to
give the full stroke position of the plungers. The piston is subjected to
servo pressure on the spring side and on the other side to pump
delivery pressure; thus, variations in the pressure difference across the
servo piston cause it to move with corresponding variations of the
camplate angle and, therefore, pump stroke.

Answer 2

PLUNGER-TYPE FUEL PUMP

Question 3

The pump is of the single-unit, variable-stroke, and plunger type. Similar pumps may be used as double units depending upon the engine fuel flow requirements.

Answer 3

PLUNGER-TYPE FUEL PUMP

Question 4

The fuel pump is driven by the engine gear train and its output depends upon its rotational speed and the stroke of the QAplungers.

Answer 4

PLUNGER-TYPE FUEL PUMP

Question 5

A single-unit fuel pump can deliver fuel at the rate of (1) gallons per hour at a maximum pressure of about (2) lb/in2.

Answer 5

1. 100 to 2,000 gal
2. 2,000 lb/in2

Question 6

The (?) is driven from the engine and its output is directly proportional to its speed.

Answer 6

GEAR-TYPE FUEL PUMP

Question 7

The fuel flow to the spray nozzles is controlled by re-circulating excess fuel delivery back to inlet.

Answer 7

GEAR-TYPE FUEL PUMP

Question 8

A (?), sensitive to the pressure drop across the controlling units in the system, opens and
closes as necessary to increase or decrease the spill.

Answer 8

spill valve