IFSTA DRIVER OPERATOR PRACTICE EXAM 2025/2026
QUESTIONS WITH ANSWERS GRADED A+
✔✔What gives multi-stage pumps their versatility and efficiency is the capability of
connecting the stages in series for maximum _____ or in parallel for maximum ___. -
✔✔Series for max pressure or parallel for max volume
✔✔When pumping in parallel (volume) position each of the impellers is capable of
flowing ___ % of the rated capacity. - ✔✔50%
✔✔Changing the transfer valve to the series position greatly increases the maximum
attainable: - ✔✔pressure
✔✔When the transfer valve is in the series (pressure) position, all the water form the
intake manifold is directed into the eye of the ____ impeller. - ✔✔First
✔✔Depending on the manufacturer, the first stage increases the pressure and
discharges ___ to ___% of the volume capacity through the transfer valve and into the
eye of the second impeller. - ✔✔50-70%
✔✔The process of switching between pressure and volume is sometimes referred to as:
- ✔✔changeover
✔✔In some departments SOP specifies that the transfer valve stay in the pressure
position until it is necessary to supply more than ___ the rated volume capacity of the
pump. - ✔✔More than ½ the volume capacity
✔✔Advances in design allow most manufacturers to specify that the pump may remain
in the pressure system until it is necessary to flow more than ____ the rated volume
capacity. - ✔✔2/3rds
✔✔The maximum net pump discharge pressure at which the transfer valve should be
operated is typically ___psi. - ✔✔50 psi
✔✔While in parallel (volume) position the pump can supply ___ of the rated volume
capacity at 150 psi. - ✔✔100%
✔✔Many power-operated transfer valves operate at pressure as high as ___ psi. -
✔✔200 psi
✔✔When the transfer valve is operated, the ___ valve allows water to escape back into
the intake, and it churns through the pump instead of building up pressure. - ✔✔Clapper
valve
, ✔✔Some manufacturers have used as many as four impellers connected in series to
develop pressures up to ____ psi. - ✔✔1,000 psi
✔✔The opening between the pump casing and the hub of the impeller is usually limited
to ___ or less. - ✔✔.01 inches or less
✔✔The first indication that wear is becoming a problem in the pump is when: -
✔✔increased engine rpm is required to pump at rated capacity
✔✔To restore the capacity of the pump without replacing the pump, replaceable ____
are provided in the pump casing to maintain the desired space between the hub and the
impeller and casing. - ✔✔Wear rings (clearance rings)
✔✔The centrifugal pump differs from positive displacement pumps that _____ results
from shutting off all discharges for short periods of time. - ✔✔Little or no harm
✔✔On pumps not equipped with a thermal relief valve, the best insurance against
overheating is to ensure that: - ✔✔some water is moving through the pump at all times
✔✔The impellers are fastened to a shaft that connects to a: - ✔✔gearbox
✔✔_____ are used to make the seals at the point where the shaft passes through the
pump casing. - ✔✔Packing rings
✔✔the most common type of packing is a material made of: - ✔✔rope fibers
impregnated with graphite or lead
✔✔As packing rings wear with the operation of the shaft, the packing glands can be
_____ and the leak controlled. - ✔✔Tightened
✔✔To overcome the heat that is developed by friction against the packing a ____ is
supplied with the packing to provide cooling and lubrication. - ✔✔Latern rings (spacer)
✔✔If the pump is operated dry for any length of time: - ✔✔it can damage the shaft
✔✔If the pump is equipped with _____ instead of packing, they will not drip and will not
require adjustment. - ✔✔Mechanical seals
✔✔_____ pumps are those pumps that are powered by a gasoline or diesel engine
independent of an engine used to drive the vehicle. - ✔✔Auxiliary engine
QUESTIONS WITH ANSWERS GRADED A+
✔✔What gives multi-stage pumps their versatility and efficiency is the capability of
connecting the stages in series for maximum _____ or in parallel for maximum ___. -
✔✔Series for max pressure or parallel for max volume
✔✔When pumping in parallel (volume) position each of the impellers is capable of
flowing ___ % of the rated capacity. - ✔✔50%
✔✔Changing the transfer valve to the series position greatly increases the maximum
attainable: - ✔✔pressure
✔✔When the transfer valve is in the series (pressure) position, all the water form the
intake manifold is directed into the eye of the ____ impeller. - ✔✔First
✔✔Depending on the manufacturer, the first stage increases the pressure and
discharges ___ to ___% of the volume capacity through the transfer valve and into the
eye of the second impeller. - ✔✔50-70%
✔✔The process of switching between pressure and volume is sometimes referred to as:
- ✔✔changeover
✔✔In some departments SOP specifies that the transfer valve stay in the pressure
position until it is necessary to supply more than ___ the rated volume capacity of the
pump. - ✔✔More than ½ the volume capacity
✔✔Advances in design allow most manufacturers to specify that the pump may remain
in the pressure system until it is necessary to flow more than ____ the rated volume
capacity. - ✔✔2/3rds
✔✔The maximum net pump discharge pressure at which the transfer valve should be
operated is typically ___psi. - ✔✔50 psi
✔✔While in parallel (volume) position the pump can supply ___ of the rated volume
capacity at 150 psi. - ✔✔100%
✔✔Many power-operated transfer valves operate at pressure as high as ___ psi. -
✔✔200 psi
✔✔When the transfer valve is operated, the ___ valve allows water to escape back into
the intake, and it churns through the pump instead of building up pressure. - ✔✔Clapper
valve
, ✔✔Some manufacturers have used as many as four impellers connected in series to
develop pressures up to ____ psi. - ✔✔1,000 psi
✔✔The opening between the pump casing and the hub of the impeller is usually limited
to ___ or less. - ✔✔.01 inches or less
✔✔The first indication that wear is becoming a problem in the pump is when: -
✔✔increased engine rpm is required to pump at rated capacity
✔✔To restore the capacity of the pump without replacing the pump, replaceable ____
are provided in the pump casing to maintain the desired space between the hub and the
impeller and casing. - ✔✔Wear rings (clearance rings)
✔✔The centrifugal pump differs from positive displacement pumps that _____ results
from shutting off all discharges for short periods of time. - ✔✔Little or no harm
✔✔On pumps not equipped with a thermal relief valve, the best insurance against
overheating is to ensure that: - ✔✔some water is moving through the pump at all times
✔✔The impellers are fastened to a shaft that connects to a: - ✔✔gearbox
✔✔_____ are used to make the seals at the point where the shaft passes through the
pump casing. - ✔✔Packing rings
✔✔the most common type of packing is a material made of: - ✔✔rope fibers
impregnated with graphite or lead
✔✔As packing rings wear with the operation of the shaft, the packing glands can be
_____ and the leak controlled. - ✔✔Tightened
✔✔To overcome the heat that is developed by friction against the packing a ____ is
supplied with the packing to provide cooling and lubrication. - ✔✔Latern rings (spacer)
✔✔If the pump is operated dry for any length of time: - ✔✔it can damage the shaft
✔✔If the pump is equipped with _____ instead of packing, they will not drip and will not
require adjustment. - ✔✔Mechanical seals
✔✔_____ pumps are those pumps that are powered by a gasoline or diesel engine
independent of an engine used to drive the vehicle. - ✔✔Auxiliary engine
