Why Is My Lawn Mower Spitting Out Grass? (All You Need To Know)

In general, lawnmowers collect the cut grass into the bags attached to them whenever you use them to mow your lawn. There are times when they spit out the grass again on the front and sides of the yard rather than gathering it into the bags. So, why is my lawn mower spitting out grass?

Overgrown or wet grass, a dull or incorrect blade, grass catcher issues, a clogged mower deck, a bad tire, and a clogged chute are just a few of the reasons that can cause your lawn mower to spit out the grass.

Why Is My Lawn Mower Spitting Out Grass? All the reasons you need to know

A lawn with clusters of trimmed grass doesn’t give a good appearance. In addition, they may result in damaging or killing the lawn grasses.

Why Is My Lawnmower Spitting Out Grass? (Possible Causes)

It’s crucial to understand the reasons behind the lawnmower spitting out grass. If you can’t identify a valid reason for this problem, the following information may help you find one:

1. Problem With The Grass Catcher

One of the crucial parts of the lawnmower is the grass catcher. As the name suggests, the grass catchers catch the trimmed grass from the lawnmower, preventing it from falling to the ground. An incorrect installation of the grass catcher results in the lawnmower spitting out the grass since it fails to catch it, which falls on the ground as a result. 

Problem With The Grass Catcher

The grass catcher is installed beneath the mower and collects the trimmed grass as it mows. A faulty grass catcher can cause a slew of issues for your lawn mower. It allows the cut grass to go below the mower, which ideally shouldn’t happen.

An incorrectly installed grass catcher is easy to re-install correctly. However, a broken grass catcher must be replaced with a new one to make the lawnmower workable again.

2. Overgrown Grass

Lawnmowers may spit out grass when the grass is overgrown. Tall grass, when mowed, spits out clumps. In this situation, it gets difficult for the user to notice the problem, leading to an ugly scenario.

 Overgrown Grass

Overgrown grass is difficult to mow down as it gets jammed underneath the deck. It also causes irregular grass spitting and the clogging of several other materials beneath the deck. When you mow overgrown grass, it may spit onto the front and sides. It’s essential to take care while mowing excessively grown grass since it’s dangerous for any lawnmower that moves over it.

Check if your lawnmower is set to cut grass at lower heights. If it is, the grass generally clusters collectively, causing the mower to spit out the grass. It results in no cutting of the lawn at all. To overcome this problem, increase the deck height and mow again.

3. Dull Or Wrong Blade

The lift blades of lawnmowers create a suction to pull the grass up into the blades to cut it cleanly. These blades come in various styles to create different lift amounts. However, the lawnmower’s motor plays a crucial role in the blade’s effectiveness. 

Dull Or Wrong Blade

You may have a blade that’s crafted to create a high lift, but the mower’s engine may not have the capacity to spin the blade at the optimum speed that generates the lift. This situation leads to uneven cutting of the grass and spitting of the grass from the sides of the lawnmower.

4. Wet Grass

Wet grass is more difficult to mow than dry grass. Wet grass clogs up the lawnmower, a common issue for many users. You will notice your lawnmower spits out grass when you try to mow wet grass. The clogged, wet grass prevents the blade from cutting the grass further.

You may have to manually collect all the grass clippings in a bag after a couple of minutes, repeating it till you are done. Using a lawnmower to mow wet grass may result in the weakening of the blades. You may even end up rusting and discoloring the blades. 

Clean the chute periodically.

5. Clogged Mower Deck

An efficient lawn-cutting process requires your mower deck to be free from dust, debris, and clumps of cut grass. It helps the grass slip smoothly through the lawnmower. A clogged mower deck results in the lawnmower spitting out the grass.

Clogged Mower Deck

Lawnmower blades may have an unchecked track to the chute, allowing them to get stuck in that area. You can prevent the clogs by:

  1. Using a sprayed or Teflon-coated deck. It doesn’t allow the grass to accumulate on the deck.
  2. Moving the lawnmower to a convenient area when cleaning gets difficult means it starts spitting out the grass.

6. Bad Tire

A tire not inflated to the mark may cause the lawnmower to spit grass. The unbalanced lawnmower starts spitting away the grass from the slightly raised side. A difference of a few psi may result in the mower moving evenly.

7. Clogged Chute

The discharge chute of your lawnmower may clog due to overgrown or wet grass. A lawnmower with a clogged chute spits out the grass in different directions. Along with the tall or wet grass, the chute may get clogged if not cleaned for a long time. Previously cut grass clippings accumulate inside, clogging it and leading to grass spitting by the lawnmower.

Why Is My Lawn Mower Spitting Out Grass: Solutions

1. Sharpening The Blade

Ensure the blades of your lawnmower are sharp. Experts recommend sharpening them at least two times per season, as per the topography.

Sharpening The Blade

A blunt-edged blade may lead to several issues, including clogged chutes and grass-catcher problems. If the blade is bent due to any hard impact, consider replacing it, as it cannot be sharpened.

2. Cutting Grass To The Appropriate Height

Cutting overgrown grass to the average height helps get the lawn mowed correctly. The grass catcher then efficiently grabs the cut grass and collects it in the attached bags. 

3. Cleaning The Mower Deck

Inspecting your lawnmower’s underside helps you understand how the excess grass has accumulated in it, hampering the overall performance. Remove the spark plug using a wrench.

 Cleaning The Mower Deck

It prevents the lawnmower from turning on while you remove the grass. Scrape off the grass accumulated on the deck using a paint scraper.

4. Replacing The Air Filter

A dirty air filter is a common reason for your lawnmower to spit grass. The apertures of your air filter may fill with dust, interrupting the fuel supply flow and affecting the overall combustion process. Therefore, it’s essential to clean or replace dirty air filters.

Replacing The Air Filter

Instead of cleaning the air filter, experts recommend replacing it. However, if you think cleaning will suffice to solve the problem, you can clean it with a few drops of liquid dish soap. In addition, use warm water for ideal cleaning. Once you clean the filter, squeeze it and allow it to dry in the air.

5. Cleaning Fuel System

If water finds its way into the gas tank, it hampers the lawnmower’s ignition. Check the gas tank for any amount of water in it. Because of the color difference, you can easily recognize it as oil floating on water.

Drain or suck out the water from the oil, and then replenish the tank with fresh fuel. 

Why Won’t My Grass Go Into The Bag?

There are several reasons for a lawnmower to spit out grass. Here are a few reasons to check and fix the problem.

  1. The grass catcher bag may already be full of grass clipping
  2. Incorrect installation of grass catcher
  3. A damaged grass catcher
  4. A clogged chute
  5. Blunt, bent, or damaged mower blades
  6. Mower height set to low
  7. Wet or Tall grass
  8. The uneven surface of the lawn

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When a lawnmower starts spitting out grass, there are several problems behind it. The issue may be caused by a clogged chute, damaged or blunt blades, improperly installed grass catcher, overgrown or wet grass, and other factors related to a poor fuel system, air filters, etc.

You must take immediate action to resolve the situation because grass clippings dumped on the lawn detract from the overall appearance of the lawn. Additionally, the grass clippings may prove to be tox

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