FIRE PUMP THEORY AND OPERATION

Question 1

Fire Pump Theory and Operation

JFRD engines are built by pierce and are fitted with midship mounted Waterous ____ ____.

These are either single-stage or two-stage and rated at _____, _____, or _____ GPM capacity.

Answer 1

Centrifugal pumps

1500, 1750, 2000

Question 2

Fire Pump Theory and Operation

Even though the various pumps differ in appearance at the pump panel, they operate in a similar manner and share construction features. In simplest terms the modern fire pump has ____ primary sections.

which are?

Answer 2

Three

• Intake manifold
• Discharge manifold
• Centrifugal pump assembly

Question 3

Fire Pump Theory Operation

JFRD engines are powered by six-cylinder turbo-charged diesel motors, manufactured by Caterpillar ( ___ or ___ ) or Cummins ( ____ ).

Answer 3

C12 or C13

ISL series

Question 4

Centrifugal Pump Theory of Operation

The impeller discharges water into _____, the chamber which directs pressurized water into the discharge manifold.

As motor speed (RPM) increases, the _____ of the impeller(s) increase.

As water enters the impeller(s) at low pressure the centrifugal force of the rotating impeller(s) increases ____.

Answer 4

volute

velocity

pressure

Question 5

Pump Shift

The pump shift control is a pneumatic switch located in the cab at the engineer position. There are 3 positions -____, ____, and ____.

Answer 5

ROAD, NEUTRAL, and PUMP

Question 6

Pump Shift

The transfer case cannot engage both ____ and ____ simultaneously.

Answer 6

PUMP and ROAD

Question 7

Pump Shift

The ____ position is used only in the event of failure with the pump shift requiring use of the manual pump shift control.

Answer 7

NEUTRAL

Question 8

Two- Stage Pumps

In PRESSURE each impeller provides pressure in _____

Answer 8

series

Question 9

Two-Stage Pumps

Utilize a ___ socket and socket wrench to change settings if the electric valve fails.

Answer 9

3/4

Question 10

Two-Stage Pumps

In _____, the supply is divided, and water is routed to both impellers at the same time

Roughly ___% of the total pressure is produced by each impeller.

the VOLUME position is also called ____ or ____

Answer 10

VOLUME

50%

Parallel or capacity

Question 11

Two-Stage Pumps

When pumping beyond 50% of a pumps rated capacity, you must be in ____.

Answer 11

VOLUME

Question 12

Two-Stage Pumps

The normal position of the transfer valve is _____ which will produce maximum pump performance for the majority of pumping scenarios.

Answer 12

VOLUME

Question 13

Single-Stage Pump

The main difference in operation from a two-stage pump is ____ ____. To pump high pressures the single stage pump requires higher ____.

A single stage pump will operate much like a two stage pump in _____.

Answer 13

motor speed

RPM

VOLUME

Question 14

Intake Piping

Each steamer intake has installed a piston intake valve (PIV) or (BIV) intake valve. Both types of intake valves incorporate a ____ ____ valve, a ____-____ ____ ____ valve, a _____ valve to bleed air from the supplies hose, and a ___ ___ adapter.

The newer BIV is less ____ (allowing higher GPM) and is rated for ____

Answer 14

Water control valve
spring-operated pressure relief valve
bleeder valve
5” Storz

Restrictive
Drafting

Question 15

Intake Piping

Both the internal pressure relief valve in PIV/BIV are preset to ___ ___

Answer 15

150 PSI

Question 16

Intake Piping

The diameter of the intake pipe is determined by the ____ ____ of the pump.

All JFRD engines have ____ Steamer intakes which allow the pump to draw the rated capacity at draft through one steamer intake (_____ GPM) or both steamer intakes( _____ and ____ GPM).

Answer 16

Rated capacity

6”

1500 GPM

1750 and 2000 GPM

Question 17

Intake Piping

The front and rear intake pipes are ___” in diameter and because of the reduced diameter will flow less than the steamers (____ GPM at Draft, ____GPM from a hydrant).

Answer 17

5”

1000 GPM “DRAFT”
1500 GPM “HYDRANT”

Question 18

Intake Piping

____ and ____ have one additional intake inside the tailboard compartment. This intake is a direct tank fill and is painted ____ to distinguish it from the other connections.

Answer 18

E-7 and E-21

Red

Question 19

Valves

The Electric front and rear intake valves take __-__ seconds to fully open or fully close.

Answer 19

15-20 seconds

Question 20

Valves

The most commonly used valves are ____ ____ ____ and ____ ____.

The ____ ____ ____ valve allows booster tank water to be drawn into the pump to be pressurized and discharged.

Once hose lines are properly set and there is enough residual pressure, open the ____ ____ valve just enough to supply water to the tank without reducing residual pressure.

Answer 20

TANK TO PUMP and TANK FILL

TANK TO PUMP

TANK FILL

Question 21

Discharging Piping

The master discharge gauge reads the ____ ____ ____ while the remote discharge gauges indicate pressure within the discharge ____ and ____ ____ only.

Answer 21

discharge manifold pressure

Piping and hose line

Question 22

Gauge Construction

Each gauge is of the ____ type.

The pressure scale reads ____ PSI, and the vacuum scale reads ___ to ___ inches.

The threaded plugs in between are only used for ___ ___.

Answer 22

compound

0-600 PSI
0 to -30 inches

pump testing

Question 23

Electric Primer

The electric primer is a ____ ____ pump driven by a small electric motor and activated by a ____ ____ on the pump panel.

Unlike the centrifugal fire pump, the primer is a ____ ____ ____ which can pump air and water.

When activated it creates a ____ within the fire pump, removing air so water can enter the pump.

Answer 23

Rotary vane
Pull handle

positive displacement pump

Vacuum

Question 24

Pneumatic Primer

Newer engines utilize a ____ ____ activated by pressing a button on the pump panel.



Answer 24

pneumatic primer

Question 25

Pneumatic Primer

If your primer is inoperative there are two alternative methods for bleeding air from the pump.

The ____ ____ discharge is the highest discharge on the pump and partially opening this valve will help purge air and prime the pump.

Small amounts of air can also be purged by partially opening the ___ ___ valve.

Answer 25

deck gun

TANK FILL

Question 26

Pneumatic Primer

NOTE: both types of primer pumps draw current from the vehicle charging system. Although you can safely operate the primer at any pressure or RPM, for best performance set the RPM between

Answer 26

1000-1200

Question 27

Motor Function Gauges

Oil pressure

Answer 27

15 PSI at idle

35-45 at speed

Question 28

Motor Function Gauges

Coolant Temperature

Answer 28

180-220 degrees fully warmed up

Question 29

Motor Function Gauges

Voltage

Answer 29

13 to 14.5 volts

Question 30

Motor Function Gauges

Transmission Temperature

Answer 30

Under 300 degrees is normal

Question 31

Pump Cooler/Recirculator

This valve controls a small discharge line that directs pump water to the ___ ___.

When opened it will flow less than ___ GPM and will remove hot pump water, to be replaced with cooler water from the supply.

If the pump is being supplied by a ____ or ____ in this valve is open, you will eventually overflow the booster tank.

This valve is generally only needed when ____ ____ are ____ but not ____.

Answer 31

booster tank

25 GPM

Tanker or hydrant

hose line are charged but not flowing

Question 32

Engine Cooler or Auxiliary Cooler

This valve operates as a ___ ___.

To prevent overheating while the pump is operating open this valve to discharge cool pump water through the ____. 

Within the radiator is a coil of tubing and pump water flows through this coil to reduce the ____ ____.

Pump water in coolant never mix. This valve should be open anytime the current temperature exceeds the ____ ____.

The ____must be engaged for this valve to function. 

Answer 32

Heat exchanger

Radiator

Coolant temperature

Normal level

Pump