Frequently Asked Questions
Can I run different types of pumps from a single
power unit or do I need one for each pump?
Will it hurt the pump to run dry?
How fast should I run the pump?
Can I drive two or more pumps from my power unit?
What is the difference between Open Loop and Closed
Loop hydraulic circuits?
Can the pump run backwards?
Do you need a case drain line on your pumps and systems?
What kind of rocks can you pump with your pumps?
Can these pumps be used to pump concrete?
What type of hydraulic oil do you suggest for your
Can you use environmentally friendly oil?
Can you burn bio-diesel in your engines?
Can I run your pump off of my existing power unit?
I have a directional valve on my vehicle. What do
I need to know to connect to this?
Can I run the pump from a skid steer or back hoe?
What is the maximum length of hydraulic hose I can
The seal blew out of the hydraulic motor on the
pump – what might cause this?
Is there a quick way to determine if my power unit
is providing sufficient flow/pressure?
Is there an easy way to determine if the hydraulic
motor on my pump is worn out?
Can I run different types
of pumps from a single power unit or do I need one for each pump?
One power unit can run several different pump models
so there is no need to have dedicated power units to drive each pump. Small power
units can drive fewer models because they are limited to the available horsepower.
Larger power units can drive more pump models and even power smaller pumps and hydraulic
tools by adding inexpensive flow controls.
Will it hurt the pump
to run dry?
All of our pumps can to operate on “snore” which means once the liquid level is
pumped down the pump can suck in air. This makes a sound like someone is snoring.
This is a typical situation and our pumps are designed to handle this “Run-Dry”
How fast should I
run the pump?
Since our pumps are variable speed, you can adjust it to suit your job conditions.
The rule of thumb is: Start pumping at a low speed then slowly increase the speed
while watching the hydraulic pressure gauge. Once the pressure stops climbing set
your speed at this point or decrease the speed slightly. This is the maximum output
speed for the job conditions. If you find that this speed causes the pump to draw
the liquid all the way down and start sucking in air or “snore”, slow the speed
down to match the incoming flow conditions.
Can I drive two or
more pumps from my power unit?
More than one pump can be driven from a power unit at the same time provided that
the power unit has enough power to drive multiple units and a flow divider or proper
flow controls are used. We also build custom power units with multiple circuits
just for this type of application.
What is the difference
between Open Loop and Closed Loop hydraulic circuits?
Most mobile hydraulic systems are Open loop. This means the hydraulic oil enters
the loop from the oil reservoir to the hydraulic pump. Then the oil is pumped to
the load (for example the hydraulic motor on the submersible pump) and then returns
back to the reservoir where it is filtered and cooled. Closed loop systems are different
because most of the oil is re-circulated between the hydraulic pump and the load.
These circuits are generally used where the job requires a small oil reservoir,
high operating pressures or precise bi-directional control. All of our pumps can
operate on open loop hydraulic circuits and most can run on closed loop circuits
using case drain lines.
Can the pump run backwards?
Our pumps as well as most all centrifugal pumps must run in one direction. Our pumps
and power units are configured so that the hose connections will not allow the pump
to run backwards. If you are connecting one of our pumps to a customer supplied
hydraulic power source, always identify the inlet (pressure) port when making this
connection. See a typical motor port orientation drawing. To prevent accidentally
operating the pump in the wrong direction, a check valve can be installed on the
Do you need a case
drain line on your pumps and systems?
Case drain lines (third lines) are used to relieve any excess pressure build-up
in the hydraulic motor casing on the submersible pump. The larger the hydraulic
flow capacity of the system, the greater the need for case drain lines. All of our
power units 25 HP (15 GPM) and above have provisions for case drain lines to be
fitted. All of our pumps that operate with input flows over 35 GPM (132 LPM)have
case drain lines fitted as standard. Pumps that operate with flows from 15 to 35
GPM only require case drain lines when you are using 150 ft. (45m) or more hydraulic
hose from the power unit to the pump. Units under 15 GPM (57 LPM) normally do not
require case drain lines and in applications over 150 ft. from the power unit to
the pump, a larger size return line can be used to reduce back-pressure.
What kind of rocks
can you pump with your pumps?
Rocks are something we do not claim to pump. Pumping rocks can damage the pumps
and will void the warranty. The only pumps we offer that can handle aggregate material
such as sand or small gravel in a slurry suspension are our Sand/Slurry pumps such
as the S3CSL,
Can these pumps be
used to pump concrete?
Our pumps are not designed to pump concrete. Concrete pumps are primarily positive
displacement pumps and are designed specifically for this purpose.
What type of hydraulic
oil do you suggest for your systems?
All of our pumps require hydraulic oils with anti wear additives (type AW) such
Rando HD. For normal use in temperate climates we use 20W oil (ISO46). In
colder climates (below 20° F. -7°C) we recommend using 10W oil (ISO32). In our smaller
systems such as the HT11D and HT13G we use Dexron ATF. This oil has a broad temperature range and
offers excellent anti-wear properties.
Can you use environmentally
In applications where the pumps are to be used in lakes, streams or other environmentally
sensitive areas we recommend using environmentally friendly biodegradable hydraulic
oils. These are available in mineral based oils such as Chevron Clarity or vegetable based
oils such as Mobil EAL224H.
Can you burn bio-diesel
in your engines?
Bio-diesel fuels can be used in some of our power models if used in accordance with
the engine manufacturers guidelines. See a technical bulletin and alternative fuels circular from
Yanmar and Deutz regarding this.
Can I run your pump
off of my existing power unit?
You can run our pumps off of your existing power unit provided the hydraulic output
(flow and pressure) meets or exceeds the requirement for the submersible pump. Most
of our pumps operate at pressures up to 2500 PSI (170bar) which is common to many
available hydraulic power sources. If your power source is capable of providing
more oil flow than is required by our pumps, a flow control can be added to circuit
to prevent over-speeding.
I have a directional
valve on my vehicle. What do I need to know to connect to this?
The use of directional valves are permitted if they are Open Center (motor spool)
valves which means that all ports are open to the tank when the valve is in neutral
or center position. If the valve has the capability to run the pump in reverse direction,
a check valve must be fitted to the return line to prevent reverse rotation. We
recommend running the return line directly back to tank (preferably through a return
filter before entering the reservoir) to prevent the possibility of reverse operation
and to alleviate the concern of whether your valve is open center or Closed Center
(cylinder spool). See Typical Hydraulic Circuit—Customer Supplied.
Can I run the pump
from a skid steer or back hoe?
You can run our pumps off of your vehicles auxiliary hydraulic circuit provided
the hydraulic output (flow and pressure) meets or exceeds the requirement for the
submersible pump. Most of our pumps operate at pressures up to 2500 PSI (170bar)
which is common to many vehicle hydraulic power supplies. If your vehicles hydraulic
system is capable of providing more oil flow than is required by our pumps, a flow
control can be added to circuit to prevent over-speeding. If your vehicle’s auxiliary
circuit is controlled by a directional valve (spool valve with lever), click here for more information.
What is the maximum
length of hydraulic hose I can run?
Two factors must be used to determine the maximum length of hydraulic hose you can
run from the hydraulic power unit to the submersible pump. On the pressure side
friction losses in the hose and couplings will reduce the amount of pressure available
to the hydraulic motor. This will cause a reduction in power from the motor and
may have an effect on the submersible pump output. On the return side friction losses
not only will effect performance but also create excess backpressure that can damage
the hydraulic motor and possibly cause seal failure in the motor. As a rule of thumb
we recommend going to a larger return hose on running distances greater than 150ft.
(45m). Use a larger hose on the pressure side on distances over 250ft. (76m). Also
see information regarding the use of case drain hoses (click here).
The seal blew out
of the hydraulic motor on the pump – what might cause this?
Seal failure on the hydraulic motor on a submersible pump is almost always caused
by excess pressure build-up in the motor casing. The primary cause for this is not
connecting the quick-disconnect couplings completely. On wing-nut style (threaded)
couplings the female coupler (wing-nut side) must be turned all the way until it
stops completely. There is usually a line on the male end that shows where the connection
is complete. Other causes can be using too long of a return hose, clogged return
hose or coupling or running the pump at full speed in cold weather without allowing
the hydraulic oil to warm up first. Also click here
and here for more information.
Is there a quick
way to determine if my power unit is providing sufficient flow/pressure?
You can quickly check to see if your power unit is providing adequate pressure.
To do this: Turn the unit off, disconnect any supply and return hydraulic hoses
from the unit, turn the HC Valve (hydraulic control valve) counterclockwise 1 turn,
start the power unit and slowly turn the HC Valve clockwise until it stops. Read
the pressure gauge. If the reading is normal (1800 to 2800 PSI depending on the
model) the unit is probably OK. If the reading is low the hydraulic pump may be
bad or the relief valve may be malfunctioning. Checking the output flow from the
power unit will require using a flow meter. Another way to quickly determine if
the hydraulic pump may be having problems is: While doing the pressure test shown
above, let the unit run for about 2 minutes under pressure, then carefully touch
the hydraulic pump to see if it getting very hot. Also listen for any strange sounds
coming from the pump and watch the pressure gauge to see if the pressure is dropping
off. These are all signs that the hydraulic pump is worn and should be repaired
Is there an easy
way to determine if the hydraulic motor on my pump is worn out?
There is no quick and easy way to determine for sure if the hydraulic motor on the
submersible pump is good or bad. Usually the first thing you would notice is that
the pumps performance seems to be dropping off. This usually coincides with a lower
pressure reading at the power unit as well. Other factors however can cause the
same symptoms such as: The pump could be air-bound; the discharge head is higher
than before causing the pressure to drop; the discharge hose could be kinked or
clogged; the impeller or wear parts could be worn. If, after checking to make sure
the power unit is OK and that the other possible causes are checked out and corrected,
the pressure is still low, the hydraulic motor is probably in need of repair or