FAQ

  1. Can I run different types of pumps from a single power unit or do I need one for each pump?
  2. Will it hurt the pump to run dry?
  3. How fast should I run the pump?
  4. Can I drive two or more pumps from my power unit?
  5. What is the difference between Open Loop and Closed Loop hydraulic circuits?
  6. Can the pump run backwards?
  7. Do you need a case drain line on your pumps and systems?
  8. What kind of rocks can you pump with your pumps?
  9. Can these pumps be used to pump concrete?
  10. What type of hydraulic oil do you suggest for your systems?
  11. Can you use environmentally friendly oil?
  12. Can you burn bio-diesel in your engines?
  13. Can I run your pump off of my existing power unit?
  14. I have a directional valve on my vehicle. What do I need to know to connect to this?
  15. Can I run the pump from a skid steer or back hoe?
  16. What is the maximum length of hydraulic hose I can run?
  17. The seal blew out of the hydraulic motor on the pump – what might cause this?
  18. Is there a quick way to determine if my power unit is providing sufficient flow/pressure?
  19. Is there an easy way to determine if the hydraulic motor on my pump is worn out?
  20. Can I pump flammable liquids with your pumps?

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” condition.

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?

Hydra-Tech 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 return line.

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, S4CSL, and S6CSL models.

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 as Chevron 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 friendly oil?

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 manufacturer’s guidelines. See a Yanmar Bio-diesel Bulletin and Deutz alternative fuels.

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 vehicle’s 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 vehicle’s hydraulic system is capable of providing more oil flow than is required by our pumps, a flow control can be added to the circuit to prevent over-speeding. If your vehicle’s auxiliary circuit is controlled by a directional valve (spool valve with lever), see question 14 above.

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 (question 7 above).

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. (See questions 7 and 16 above.)

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 or replaced.

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 pump’s 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 replacement.

Can I pump flammable liquids with your pumps?

In some circumstances (mechanical seal choice, catastrophic failure, improper operation, etc.) there is the potential for metal on metal contact and heat or spark generation as a result.  Because of this (unlikely but not impossible) potential situation we recommend against pumping flammable liquids.

 

Top