An impact sprinkler uses the force of water to spin a rotating arm, distributing water over a large area with its characteristic clicking sound. Proper adjustment is necessary to ensure uniform coverage and avoid wasting water on sidewalks or driveways. Fine-tuning the spray pattern and distance allows you to efficiently irrigate your lawn, maximizing water conservation and promoting healthy grass growth.
Identifying Key Adjustment Parts
The base of the sprinkler head features several components that control its movement and spray characteristics. Two adjustable metal or plastic clips, known as friction collars or arc stops, define the boundaries of the sprinkler’s rotation. A small wire or lever, often called the trip pin, rides along the base and interacts with these collars to change the direction of the water stream.
Located near the water nozzle is the diffuser pin, a small screw that can be moved into the path of the water stream. Some models also include a deflector shield or stream straightener, which is a flat piece of metal or plastic that can be flipped up or down. These parts modify the trajectory, distance, and consistency of the water being sprayed.
Setting the Rotation Angle and Arc
Defining the specific area the sprinkler covers is achieved by manipulating the friction collars and the trip pin. For full 360-degree watering, the trip pin must be lifted and secured against the sprinkler head, bypassing the collars entirely. This allows the head to rotate continuously in a full circle, suitable for placement in the center of an open lawn space.
To water a partial arc, such as a 90-degree corner or a 180-degree strip, the trip pin must be engaged by leaving it in the down position. The two friction collars are then positioned to mark the start and end points of the desired watering zone.
As the sprinkler rotates, the trip pin contacts the first collar, triggering a mechanism that reverses the rotation. The sprinkler moves in the opposite direction until the trip pin hits the second collar, causing the rotation to reverse again. Sliding the collars closer together narrows the arc, while moving them further apart widens the watering range.
Controlling the Water Stream Distance and Pattern
The distance the water travels and the uniformity of the spray pattern are managed by adjusting the diffuser pin and the stream straightener. For a shorter, softer spray to water nearby areas, the diffuser pin should be screwed clockwise into the path of the water stream. This action breaks up the solid jet into smaller droplets, causing it to fall closer to the sprinkler head in a finer mist.
For maximum distance, the diffuser pin should be unscrewed completely out of the water stream, allowing for a concentrated, solid jet. The deflector shield, if present, can be lowered into the stream to create a flatter, lower trajectory for shorter throws. Alternatively, it can be raised out of the way for a higher arc and greater reach.
The speed of the sprinkler’s rotation is controlled by the tension of the hammer spring or clip on the impact arm. Adjusting the spring tension, typically by bending the wire or moving it to a different notch, can slow down or speed up the rotation. A faster rotation ensures a more uniform water distribution, while a slower rotation allows the water to soak deeper into the ground at each point.