Troubleshooting Problems with an Oscillating Sprinkler

An oscillating sprinkler on a green lawn.

A quick and easy option for watering the lawn is with an oscillating sprinkler. This simplistic mechanism has been around since the late 1800s and still going strong. The operation of an oscillating sprinkler looks straightforward with minimal moving parts to regulate the water. But while sprinklers can have issues specific to their particular model and manufacturer, there are several basic problems many oscillating sprinklers experience.

Water Hose Problems

Whenever the sprinkler is not working at its best or not at all, there are a couple of areas that could be causing the problem. It doesn’t take much to cause an oscillating sprinkler to malfunction.

If the sprinkler is coughing and sputtering with limited water being emitted, the problem could be as simple as air in the hose because of a crimped line. To eliminate the problem, turn off the water and disconnect the hose from the sprinkler.

Straighten the hose line, allowing built-up air to escape. If your hose has a weak area due to age or damage that causes the crimp, replace it so the sprinkler has access to a direct flow of water.

A twisted garden hose on a green lawn.

Check the hose connection point for gushing water. This will interfere with the sprinkler’s operation and may only need a hose gasket installed or replaced.

When you next purchase a new water hose, consider the brands that manufacture non-crimping water hoses to avoid future problems.

Low or High Water Pressure

Since an oscillating sprinkler is dependent on regulated water pressure to disperse a constant spray to lawns, having too much or too little affects the sprinkler's operation.

When the water pressure is too low, there isn’t enough pressure to move the distribution/cylinder bar back and forth. Depending on how low the water pressure is, the sprinkler can move extremely slow to one side, but may not have enough pressure for it to pivot back. This results in no oscillation. In other models, the cylinder bar may not move at all, remaining in a stationery position.

Troubleshooting for low pressure is easy enough. First, check for crimps in the line. Next, increase the flow by turning the faucet clockwise. The problem may only require more water power. Observe the sprinkler to see if increased water affects the sprinkler motion.

If it still does not operate properly, it may be that the water pressure on your property is to too low to accommodate the need of an oscillating sprinkler and you may need to purchase a different model. Check the manufacturer’s information regarding the use of the sprinkler with low or high water pressure.

A close-up image of an exterior water faucet.

High water pressure creates its own problems for sprinklers. The internal structure of an oscillating model revolves around gears that interact with the water to create the oscillating motion. Whenever the water flow is too strong, the pressure can work against the gears, causing them to work contrary to their design specifications.

When the gears don’t operate according to design, it can result in the bar not moving at all or moving in an erratic motion. Either can cause the gears to become unaligned and can result in permanent damage or breakage.

To avoid too much water pressure, adjust the faucet to a lower level to determine if it makes a difference in the sprinkler’s operation. If it does not, you may need to purchase a pressure regulator from a plumbing company or home improvement center.


Rust, corrosion, and grime buildup is problematic. Wipe the sprinkler with a clean cloth and then apply spray lubricant to each end of the oscillating arm for smooth operation.

Remove any obstructions that may interfere with the sprinkler’s operation, including tall grass, weeds, gravel, or mulch. Because of its low design, anything that inhibits the cylinder/arm causing unnecessary rubbing may cause the sprinkler to not rotate properly, or at all, resulting in stripped or dislocated gears.

Oscillating Sprinkler FAQ

Why is my oscillating sprinkler not oscillating?

If even one of your sprinklers isn't moving across the lawn the way it should, your grass is not getting even water distribution and this could lead to patchy areas of the yard that will be unappealing. Oscillating sprinklers may stop moving for a few different reasons.

The quicker you can identify why the sprinkler isn't moving, the quicker you can give your lawn the moisture content it needs.

Check the distribution cylinder. If this is not centered, it will prevent the sprinkler head from moving the right way.

Low water pressure, high water pressure, kinks and crimps in the hose, a clog on the nozzle, and debris surrounding the sprinkler head can all keep the sprinkler head from rotating the right way.

How do you unclog an oscillating sprinkler?

Water contains minerals and in time, these minerals can form deposits that build up on faucets and fixtures that supply water. That includes sprinkler heads.

Mineral despots can clog sprinkler heads and keep them from working and turning properly. To fix this, remove the sprinkler head and place it into a resealable bag with liquid rust remover inside.

Close the bag and shake the sprinkler head gently around, swirling it inside the solution, then let it soak for about 30 minutes. Give the bag another good swirl before you remove and thoroughly rinse the sprinkler head.

Use a hard-bristle wire brush to clean away rust and grime. Put the sprinkler head back into position and test it to see if the clog is gone.

Why is my sprinkler head only turning one way?

If your sprinkler head is turning partially but not all the way, turn off the system and access the filter. Debris may have built up there that is now affecting the water flow.

Remove the filter for the sprinkler system, clean it off, and put it back in place.

How do you bleed air from a sprinkler valve?

Sometimes, you might need to "bleed" your sprinkler system. This means you need to remove water from the system and this is something you need to do once a year in order to winterize your sprinkler system.

Bleed the sprinkler system with a portable air compressor. Turn off all the water to the system and connect the bleed valve for the system to the air compressor.

Turn on the compressor to send air through the system. You only need to blow the air for a couple of minutes.

Once the lines are bled, seal off the lines so no water gets in them through the winter.

Why are only half of my sprinklers working?

Some sprinkler systems operate on a zone basis, which means each zone contains a few nozzles that work in their own semi-closed system. If there is a leak or an electrical problem anywhere in a particular sprinkler zone, it can cause all the sprinklers in that zone to stop working the right way.