PLEASE NOTE: The maximum (suction head) depth that a petrol or diesel water pump can lift (Suck) water is 2.5 metres at 1600 metres above sea level. If the water source depth is greater than this you will need to consider using an electric submersible pump and, if there is no power you will need to use a generator. We have many inquiries for diesel pumps from people who believe that it is possible for pumps to lift (suck) water from depths of up to 100 metres sadly, they have been misinformed. If anyone claims that their pump can lift (suck) water greater than 8 metres at sea level please contact us to confirm the specs. 

Pumps can be used for a variety of applications but the most common use is for pumping water. Pumps can be driven by petrol, diesel or electric motors. There are many types of water pumps such as clean water pumps, trash pumps, submersible pumps and bore hole pumps. 

When selecting a pump there are two important criteria that must be determined-Volume (Litres or cubic metres) to be pumped and head (height from the pump to the outlet) required. Generally, the greater the head the more power will be needed to pump the same amount of water. Most pump manufacturers have graphs which show volume vs head vs power required. 

The suction head which is the distance from the water to the pump should be kept to a minimum. Try not to exceed 5M as it will cause the water to boil in the pump (Boyles Law). Priming  the pump can also be difficult. If the suction head is excessive consider using a submersible pump or move the pump closer to the water. 

Always make sure that a strainer is fitted to the suction pipe inlet. If possible try to keep the suction pipe inlet raised off the bottom. 

Types of pumps:

Clean water pumps-These are usually made from plastic or aluminium. They cannot handle any solids and should not be used to pump dirty water as this will damage the pump. The pipe diameter can vary 2", 3" and 4" are the most common sizes The bigger the diameter the greater the volume of water to be pumped. These can be used for irrigation, emptying pools etc.

Trash pumps- These are usually made from cast iron, steel or aluminium lined with steel. Used for pumping dirty water and they can handle solids such as sand and small stones. Typical uses are emptying trenches, mines etc.

Submersible pumps- Can be made from a variety of materials. These pumps can be electrically driven or  a flexible drive unit. The electrically driven pumps will need a generator if there is no power source. Submersible pumps can handle very large heads but this will depend on the volume required and the power of the motor. Common uses are mines or irrigation. 

If you would like assistance selecting the correct Pump please email us your requirements or telephone and speak to one of our technicians.  

Call Martin Drewett on 079 192 7714 or email