When you feel like your EGO electric mower is starting to shake, shut off your mower, remove the safety key, and remove the battery so you can inspect the mower blade and motor shaft.
An EGO lawn mower vibrates when the mower blade is installed incorrectly, the blade is bent, or the blade is not balanced.
If the mower blade impacted a foreign object, the motor shaft may be damaged leaving a vibration.
Stay safe by following the safety instructions found in your operator’s manual. Wear heavy work gloves when working with sharp blades.
This post may include affiliate links. Purchases made through these links may provide a commission for us, at no extra cost to you. As an Amazon Associate, we earn from qualifying purchases.
Follow all safety instructions provided in your equipment operator’s manual before diagnosing, repairing, or operating. Consult a professional if you don’t have the skills, or knowledge or are not in the condition to perform the repair safely.
This is Why Your EGO Lawn Mower Vibrates & Shakes
1. Blade is Loose and Not Installed Correctly
The mower blade is often the reason your EGO starts to shake. Check to make sure the blade is installed correctly and securely attached.
Install the blade and parts in the right order
When installing the mower blade, make sure the blade parts are installed in this order:
- Install the flange before installing the mower blade.
- Push or self-propelled mower: The inner is mounted to the fan. The fan and inner flange are then mounted to the motor shaft. Make sure the fan blades are pointed toward the mower deck.
- Zero-turn mower: The flange is mounted to the motor shaft.
- Place the blade on the flange with the side that is printed “THIS SIDE FACING GRASS” facing toward the outside. If you don’t find your blade printed with this message, just make sure the blade sails are pointed toward the deck. The sails are the high sides of the blade.
- Install the washer and insert the blade bolt into the shaft and finger tighten.
- Move the blade to align the holes in the blade with the holes in the flange.
- To keep the blade in this position while you tighten the blade, place a screwdriver or other similar item in one of the holes in the blade.
- Next, place another screwdriver in the fixing hole to keep the blade from spinning.
- Tighten the bolt using a torque wrench to the specifications listed in the owner’s manual for your specific model.
- Push or self-propelled mower blade: Torque to 36-43 ft-lb.
- Zero-turn mower blade: Torque to 36-41 ft-lb.
2. Mower Blade is Bent
When your blade impacts a solid foreign object like a rock or stump, it can bend causing your EGO mower to give a bad cut.
To prevent damage to the blade, it’s a good idea to walk the lawn to make sure there’s nothing in the way that you may run over and damage the mower.
A bent blade will cause an uneven cut. It can also cause your mower to start vibrating. Sometimes a bent blade is obvious and sometimes not so the best way is to remove the blade.
Make sure your mower is parked on a flat-level surface and remove the battery pack(s). Wait for all moving parts to stop moving before working under the mower deck.
- Check for a Bent EGO Mower Blade By Removing the Blade
Remove the blade and lay it on top of a new EGO mower blade if the bend isn’t easily noticed by looking at it. This is the best way to verify whether or not your blade is bent. Even a very slight bend can cause a bad cut.
Replace a bent blade with a new one. NEVER attempt to straighten a bent mower blade to reuse it. When you do this, the metal is compromised and becomes weakened.
It is possible for the weakened area to break off and fly out of your mower deck at high speeds. This could cause injury or damage to people, pets, or objects in the area.
3. Mower Blade is Not Balanced
It is necessary to balance your mower blade before reinstalling your EGO mower. Failing to do so can cause vibration and damage to the motor shaft and cause you to feel a vibration.
A balanced blade is one that has equal weight on each end of the blade. A blade can become unbalanced when dirt wears the blade unevenly or when removing more metal from one one of the blade during the sharpening process.
Use a blade balancer to check the balance of your blade. If you don’t have a blade balancer, you can place a nail in the wall with the nail head about 3/4″ to 1″ away from the wall. Place the center of the blade on the nail.
Another option is securing a screwdriver in a vise so the metal end of the screwdriver sits horizontally. Place the center of the blade on the screwdriver.
You want the blade to sit level while balancing on the nail head or screwdriver. If it doesn’t, shave a little more metal off the side of the blade that is hanging lower until it sits even with the other side.
4. Bent Motor Shaft
A bent motor shaft will cause the blade to wobble causing your EGO mower to shake. You may be able to tell there is a problem with the shaft by grabbing a hold of each end of the blade and checking to see if there is extra movement.
If the blade is installed correctly and you suspect a problem with the shaft, have an EGO service center identify and repair the problem.