Water Pumps-all you need to know
Water Pumps are necessary to circulate coolant through the car engine’s water ports, to transfer heat which is caused my friction of the internal combustion engine’s moving parts, to the radiator.
Bringing in cooled liquid, to repeat this process, continually, as long as the engine is running.
This process helps regulate the engine temperature and prevent over heating.
Water Pumps are mechanical and electric powered.
The most common used is the centrifugal water pump(mechanical).
Electric water pumps are used mainly as auxiliary pumps in a few high performance car models/brands.
Centrifugal Water Pumps were invented as early as 1687-French-born inventor Denis Papin developed the first true centrifugal pump, one with straight vanes used for local drainage.
Water Pumps were used in car’s since the Internal Combustion Engine was invented back in 1883 and has seen vast improvements over the years even being electrified in our modern age.
Made from various metals such as Pewter, Cast Iron, Mild Steel, Aluminium.and even high heat resistant Plastics.
In earlier years water pumps were made to be serviceable where kits were available and the main body of the Water Pump was re used and all wearable parts could be replaced, like impellers, bearings and seals.
In our modern times, it is made as a sealed unit, to be removed, discarded and replaced when worn.
The Water Pump works in conjuction with many other components which together makes up the cooling system, namely
- Resevoir/Radiator Cap
- Fan Switchs
- Fan Belt
- Hoses and Pipes
- Auxilary Pumps
In this post I will focus solely on the Water Pump.
A Typical Centrafugal Type Water Pump
How the Centrifugal Water Pump Works
Coolant is drawn into the engine by the Water Pump impeller, connected to the engine’s cooling system, as the impeller spins, centrifugal force flings the coolant toward the outlet port incorporated into the pump, which leads to the water jackets in the engine.
The coolant is forced through a restriction to the outlet water jacket, in so doing causing the water to pressurize, allowing a stronger flow through the engine.
The coolant is then able to flow faster through the engine and reach areas further away from the Water Pump, quicker.
It also allows the cooled liquid to return quicker in order to transfer heat away from the engine faster, keeping the car’s operating temperature constant.
This is commonly known as coolant flow pressure.
What Drives the Water Pump ?
Centrifugal Water Pumps are driven by a Fan Belt or the Cam Belt/Timing Belt
Power is taken from the crankshaft, transferred through the Fan/Cam belt to the Water Pump pulley.
In most modern cars today, the Fan Belt also provides power to other components such as:-
- A/C Compressors
- Power Steering Pumps
- Tensioners and Idler Pulleys
The pictures below illustrates the different belts that drives Water Pumps, namely Cam Belts (pictured on the left) and Fan Belts (pictured on the right)
Electric Water Pumps
Electric Water Pumps perform the same function as centrifugal pumps, except that it is driven by electric as opposed to a belt, it is mainly used as auxiliary pumps in high performance engines, where higher water pressures are required.
Signs of Water Pump Failure
- Noisy Impeller Bearing
- Excessive wear on the Impeller Bearing
- Leaking Weep Holes
- Leaking Water Pump Main Gasket/Seal
- Higher than normal engine operating temperatures(worn Impeller)
- Premature Fan Belt wear
- Significant power loss in the case where the Cam Belt drives the Water Pump
- Cracked Water Pump Casing.
I hope this is helpful to you and that you find value in it.