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Correct lawn mower blade height is essential for getting perfect cuts. When set correctly, it trims grass more effectively, leaving it with an appealing look. Here we look at how to adjust lawn mower height to get the perfect length of grass for your lawn.
Equipment Needed for Adjustment
Before you adjust your lawn mower height, you need a ruler and a wrench set. An air pump and a pressure gauge are required for measuring tire pressure. Take precautionary measures, such as wearing gloves, before handling the blades.
Adjusting Cutting Heights
The following are ways to increase cutting heights on various lawn mowers.
Riding Lawn Mowers
The blades on riding lawn mowers are mounted under the mowing deck, which has a separate connection to the lawn mower’s main body. Height adjustments are made with lift links. The first step is to park the mower on a flat base by setting the parking brake. Use the driveway, as its surface is more even, and it will be easier to locate nuts and screws.
The next step is to take precautionary measures, since you are handling blades to make adjustments. The best idea is to turn the engine off by removing the ignition key. Removing the key prevents the engine from turning on by accident.
The third step is to adjust tire pressure to ensure the mower is not tilted to one side. A tire pressure gauge keeps the pressure equal, hence the need to keep the mower leveled. The air supply can be used to fill up the tires.
Using the lift link, raise the deck from side to side. Lift links allow you to lower or raise the deck. A full turn can raise or lower a particular side by 3/16 inches. Turn the blade, then measure the height from the ground with a ruler.
After adjusting the lift link and getting the desired level, measure the height of the blade tip and repeat for the other side of the deck. Ensure that the final height of the blade tip on both sides is the same to prevent uneven cutting patterns caused by unequal blade tip levels.
The last step is to raise the deck using the adjustment nut from front and back. Ensure the mower rake or pitch is within the required limits. To achieve this, align the tip of the blade longitudinally or in a front to back direction, then separately measure the tip’s height from the surface.
The front is set ⅛ to ½ inches lower than the back to prevent the cutting section from scattering grass over the lawn. Adjust levels from the front to back with the nuts provided. Ensure that you stay within the required values for any adjustments performed as detailed in the manual.
Self-Propelled Lawn Mowers
The cutting blades in self-propelled lawn mowers are placed under the deck. The deck is connected permanently to the main body, unlike with riding lawn mowers. This prevents it from being raised or lowered.
The first step is to park the mower on a flat surface to prevent height errors and keep the blade level. If it is gasoline-powered, disconnect the spark plug wire or turn off the engine.
Next, locate the height adjustment lever. They are usually placed on the inner side of the tire, where contact with notches can be made. The lever raises and lowers tire levels, thus varying the height.
The next step is to push the lever backwards or forward to lower or raise the height of the wheels. To increase height, turn the lever forward and fix it into the notches. Repeat this procedure for every wheel and ensure that they are all leveled to prevent uneven cutting patterns.
Electric Lawn Mowers
Height adjustments for electric lawn mowers are almost the same as previously discussed. The adjustment lever should be stretched out. It would be best to move back the lever to a higher number of the deck to cut at high levels, or to a lower number to cut at lower heights.
Ensure that the wheels are leveled by double-checking after making adjustments.
Height Adjustment Systems
The following are common height adjustments systems used in lawn mowers.
This is considered the most basic type of adjustment. In this method, the wheels are physically removed and placed in a higher setting with the help of a snap-in feature. It is mainly used on entry-level machines and plastic wheeled lawn mowers.
In this method, every wheel is fitted with a lever for adjustment. The levers on every wheel are placed in the same setting to make a perfect adjustment.
This system is also referred to as central single lever adjustment, and is used in many top-end lawn mowers. It uses a single lever placed near the axle of the machine to raise the deck level.
Single Lever Rear
This is very similar to the single-lever system. One lever is used to raise the back of the deck, while the front wheels have their separate levers.
In this system, a knob, dial or handle is used to turn and make different settings. This is the easiest system to use, and it saves time.
Safety Measures to Observe
Safety should always be the first thing to observe when making any adjustments on your lawn mower. The following are some safety measures to take.
Turn the Engine Off
Adjust the cutting height before turning on the engine. Height adjustments should not be made when the blade is in motion. This reduces accidents as well as damage to the lawn mower. Also, shut off the motor when checking the undercarriage of an electric lawn mower.
Put on Gloves
Wear gloves when touching the blades. You can still get injured even when the engine is off. Leather gloves are preferred for this operation. Protect your eyes when testing the lawn mower after making height adjustments.
Making the correct height adjustments will give you outstanding results. Follow the directions included in the manual to know the best height setting for you, depending on the pattern needed. Also, observe safety precautions as advised by the manufacturer.