By Roelof Bezuidenhout
If you still have a working windpump (sometimes called windmill) on your land, take good care of it. Farmers often neglect these simple, reliable, essential machines. With minimal maintenance, a windpump can last for 50 years or more, with no running costs – although the price of pipes and spare parts have skyrocketed.
If a windpump breaks, you could be in for a headache. A new one will set you back at least R60 000, and skilled windpump mechanics are hard to find. Depending on the damage, it might be worth switching to a solar pump, which starts at about R12 000. Second-hand windpumps are widely available and affordable, but transporting one is no easy task.
Windpumps – which have been in use since the 1880s, when their towers were made of wood – still have some advantages over modern solar pumps. One key benefit is that they can operate in areas that don’t receive sunlight all day – and they keep working at night as long as there’s some wind.
It’s also possible to combine the two systems by installing a solar pump (if small enough) just below the windpump cylinder in the borehole. Be careful, however, not to over-pump the aquifer. You can avoid this by setting a timer on the solar installation, controlling it via cellphone, or angling the panels so they only receive sunlight until around 3 pm – when the wind typically picks up and the windpump can take over. This setup ensures they don’t run simultaneously for most of the day.
Another advantage of windpumps? They’re nearly impossible to steal – unlike solar panels, which are always at risk of theft.
Maintaining a solar setup has become significantly cheaper than keeping a windpump in working order. Galvanised pipes have become really expensive, however, and replacing them requires at least three people. Solar pumps are much easier to install, but some brands require more frequent servicing, especially in areas where metals or other impurities are present in the water.
Windpump maintenance checkup
• For windpumps, the first thing to check is always the oil level. Running the system dry will quickly wear out the gears and axles in the head. Don’t wait for the mechanism to start squeaking before adding oil – and use the recommended type rather than thick, old motor oil. Ideally, the oil should be replaced every few years.
• Next, inspect every nut and bolt from the base of the tower to the wheel. A single loose blade can quickly lead to others loosening, and if left unchecked, a strong wind could fold the wheel over the head (see photo).
• Make sure the hood on the head is secure. You don’t want rainwater to mix with the oil in the sump.
• Make sure the brake works. You need to stop the machine when replacing pipes or when the dams are full – and you want to slow it down in strong winds.
• Grease the baseplate nuts so that you don’t have to saw them off when you pull out the pipes.
• Check for ants. They like climbing up the tower, and then land up in the sump where they turn the oil into an abrasive paste that can damage the gears.
Perform this maintenance checkup twice a year, and your windpump will last for many years to come.
A final piece of advice
When replacing pipes, apply a small amount of grease to the joints to make them easier to loosen next time. This also helps prevent the monkey wrenches from damaging the metal, which could weaken it and lead to leaks. Grease could also possibly help to retard rusting, but that might just be a theory. When putting the pipes back into the well, rinse the insides with clean water to remove any rust or debris. This prevents debris from entering the cylinder, where it could either keep the valve open or block the plunger, potentially damaging the top rod.
 | Roelof Bezuidenhout is a fourth-generation wool, mohair, mutton and game farmer and freelance journalist. Attended Free State University, majoring in animal husbandry and pasture science. Other interests include golf, photography and geology. |
