Cutting your grass with a mower provides an appealing and a perfectly manicured lawn. However, it comes along with some challenges, you may wake up early in the morning to mow your lawn and then oops! You realize the mower is not cutting the grass. So, why is lawn mower not cutting grass?
Damaged blade is the most common cause of mower not cutting grass, this problem can also result from other causes that include: poor engine performance, low throttle, clutch slip, too low deck, wet grass and a full grass bag.
Why is my Ryobi Lawn Mower Not Cutting Grass?
The most common cause of Ryobi lawn mower not cutting grass is due to a dull or damaged blade. However, there are also other reasons that include:
1. Dull or Damaged Blade
Dull blades can cause all sorts of problems to your lawn such as not cutting the grass or leaving behind uncut grass. Blunt blade can also damage your lawn. Instead of cutting each blade of grass cleanly, it tears the grass. The ragged edges may turn the grass tips yellow or become entry points for infections.
Mower blades have it tough when cutting the grass. It can become damaged after hitting stones, stumps, water pipes and sprinklers. Be sure to check for loose bolts, misaligned, damaged, broken or bent blade tips.
Misaligned, bent or broken blade tips may not cut the grass. It is also dangerous to use a bent blade, it can damage the mower engine. It is recommended to change the blade when it is damaged or worn-out. Be sure to replace the blade washers and bolts too.
2. Poor Engine Performance
Poor engine performance results from use of old fuel. Fuels older than a month may clog or gum inside the carburetor and block the fuel feed ports. When fuel is left for more than a month, some of the ingredients in the gas evaporates leaving behind thick and sticky substance that clog carbonator. The engine become sluggish with less power not cut the grass.
3. Wet or Too Tall Grass
Is your grass wet or too tall to be cut? Before answering this question, let’s first look at the condition of your grass to examine if it’s wet or too tall. It is difficult to cut grass in wet conditions as compared when dry. When the grass is wet and taller than normal, it may lay down easy when rolled over by a mower. So, the blade will not be in a good position to cut it off.
You are literally pushing down the grass rather than cutting it off as you’re expecting. Mow your lawn regularly when it is dry. Don’t let your grass to overgrow and mow when it’s wet.
4. Low Throttle
Ryobi lawn mower requires a full throttle to produce enough energy to cut off the grass. Low throttle can cause the engine to be a bit sluggish. Check the cables to ensure they are well connected to the carburetor. The lever may be set to a full throttle but the cables may not be reaching the carburetor end.
Low throttle results from dirty air filter. Dust and other air particles can accumulate in the air filter after using the mower for a long period of time. This may reduce the efficiency and performance of the engine. It may not produce enough power to spin the blade fast.
5. Clutch Slip
The clutch which is also known as PTO (power take-off) helps to transfer the engine powers to the blades. When having mechanicals problems, it may slip. Therefore, the blades won’t be able to spin with the same power as normal. Clutch slip is characterized by low power especially when cutting thick or heavy lawn.
6. Too Low Deck
The deck on your lawn mower plays an important role of guiding the cut grass into the bag. It also prevents the grass from falling back on the lawn or clogging the deck area. When mulching, the deck helps to recycle the grass clipping so as to be cut into tiny pieces that are dropped back into the lawn. When the deck is too low, it can cause grass build up underneath. This can stop the blade from cutting.
7. Grass Bag Too Full
Check the grass bag and empty it when full. Continuing to mowing when the grass bag is full can lead to clogging of the area between the deck and the blade. This can prevent the blade from spinning to cut the grass.

Ryobi Lawn Mower Blade Not Spinning
Turned on your mowers and realized the blade is not spinning? Several factors can keep your blade from engaging. There are some tips to consider when troubleshooting your Ryobi lawn mower blade that is not spinning.
Consider Safety First
Prior to troubleshooting your mower, understand all the precaution signs and warnings. Power off your mower before putting your hands in the blades to check if they are obstructed or not. Ensure the lawn is on a concrete floor or in a garage before loosening any bolts. You do not want some of the tiny bolts to get lost in the tall grass.
Start by Reading Manufacturer’s Manual Recommendations
Instead of going to Google search and YouTube videos, read and understand the manufacturer’s recommendations on troubleshooting the problem. You might be lucky to fix the problem just right away. Ryobi lawn mowers comes with a manual. It contains information on some of the common problems and how to fix them.
Check the Power Supply
Ryobi lawn mowers may be powered by electricity, gas or batteries. Check if the electric cables are well connected to the main power source, if the gas tank is filled with fuel or if the batteries are fully charged. The blades may not engage if your unit is not receiving sufficient power.
Remove Obstructions
If your mower runs but vibrate badly and blades barely engages, try to check the deck for any obstructions. Obstructions from big junks of grass and other foreign materials like stones can jam the mowers blade from spinning normally. If there is something that is causing the obstruction, power off the mower and remove it. Try to run your mower again.
Check the Drive Belts
Drive belts on the mower’s deck work in co-ordination with power take-off to spin the blades. When the drive belts are worn out or damaged, the blade also won’t spin. Check and replace if they are worn-out. Ensure they are routed properly during installation. The blades also won’t engage when they are poorly routed.
How to Fix Ryobi Lawn Mower that’s Not Cutting Grass
Mower’s problems can be frustrating especially when you can’t figure out the cause behind it. These guidelines can help you to fix some off the common problem.
1. Sharpen Dull and Replace Damaged Blades
Inspecting the mowers blade regularly helps to determine if it is blunt or damaged. If the blade is blunt, use a file to sharpen it. Sharpen the blade using a file for at least once per season or depending on how often you use your lawn mower. A sharp blades cuts the grass cleanly, allowing it to heal quickly.
If the blade is misaligned, bent or broken, then it is time to replace it. It is dangerous to use a lawn mower that is having a damaged blade. A new blade will solve many problems such as not cutting grass. When replacing the blades ensure to get new bolts and washers too.
2. Mow at a Full Throttle
Read manufacturer’s instructions to check if the throttle is set correctly. The lever should be set full when mowing. Also check the throttle cables to ensure they are adjusted correctly. The engine is supposed to run perfectly in order to generate enough power to cut the grass.
3. Use Fresh Fuel
Avoid fueling your lawn mower with old or bad gasoline. Using fuel stored for over 1 month can be detrimental to your lawn mower. It may clog carburetor chambers. Drain the fuel tank, clean the carburetor and refill with fresh gas to resolve this issue. If you are intending to use the gas for a long period of time, try to use fuel stabilizers to keep it fresh.
4. Free Obstructions
Remove rocks and other foreign objects that may be lodged in the mowers PTO (power take-off). PTO helps to transfer power from the engine into the blades in order to spin. When foreign materials are lodged in, it may not be able to transfer enough power into the blades.
5. Replace Worn Out Drive Belts
Drive belts on the mowers deck work hand in hand with PTO mechanism to engage and disengage the blades. The drive belts may not engage when they are damaged or worn out. Be sure to install them properly when replacing. May also not work properly when installed wrongly.
6. Clean out the Mower
After using your lawn mower, ensure it is cleaned properly. Remove grass stones and other foreign materials that may be plugged in the deck. Inspect the deck to find out if it is damaged. Tighten loose bolts and grease the blade joints for a smooth spin.
Final Thought
It is a good thing to have a mower, it helps to maintain your lawn into a desired levels. However, there are several problems you are likely to encounter when using a lawn mower. Know all the safety precautions and warnings. Also read and understand the manufacturer’s recommendations when troubleshooting your mower.