Mammotion Luba Blades Not Spinning or Not Cutting the Grass
- Wet grass packed under the discs and guards
- Seized floating cutting deck from packed grass dust
- Loose or cracked blade disc throwing the balance off
Problem Description
The Luba drives around but the cutting discs do not spin, it leaves the grass uncut, or it throws a cutting or lifting mechanism error and stops. On the Luba the three cutting discs ride on a floating deck, and wet grass packed under the discs and guards is what jams them almost every time, so this is usually a cleaning job rather than a broken motor.
Why This Happens in Real Homes
On the Luba the three cutting discs ride on a floating deck, and wet grass packed under the discs and guards is what jams them and trips a cutting or lifting mechanism error nearly every time, so this is usually a cleaning job rather than a broken motor. In real yards the mistake is letting matted clippings build up under the deck between mows.
Power off, clear the packed grass, free the deck, and check the discs and blades before assuming the sensor or motor has failed.
Symptoms
- Robot drives but the cutting discs do not spin
- Grass left uncut behind the mower
- Cutting or lifting mechanism error and it stops
- Discs jammed and will not turn by hand
- One disc spins but another does not
- Motor faults shortly after starting
- Blades cut raggedly, leaving tufts standing
- Error appears after mowing long or wet grass
Recognize these? Here's what usually causes it.
Common Causes
- Wet grass packed under the discs and guards
- Seized floating cutting deck from packed grass dust
- Loose or cracked blade disc throwing the balance off
- Loose center nut on the disc collar
- String or wire wound around a disc shaft
- Dull, bent, or worn blades
- Bent disc after hitting a root or stone
- Failed lifting-mechanism sensor or blade motor
Most fixes happen in the first 3 steps.
The cutting blades are sharp and can start without warning. Always stop the mower in the app and switch off the main power before reaching under the deck, and wear gloves when handling the blades.
Step-by-Step Solution
Power down and get under the mower safely
Stop the mower in the Mammotion app and switch off the main power switch before you go near the blades. Tip the Luba onto its back or side on a soft surface so you can see the three small cutting discs on the underside, each carrying pivoting razor blades. Never work around the blade area with the mower powered on, since the discs can spin without warning.
Clear grass packed under the discs and guards
The most common trigger for a cutting or lifting mechanism error is wet, matted grass built up between the discs, the blade guards, and the mower body, which physically stops the discs turning and jams the deck. Pull and brush out all the caked grass around the discs, the guards, and the screw holes until each disc turns freely by hand. In heavy growth this needs doing every couple of weeks.
Free the floating cutting deck
On the Luba the disc assembly rides on a lifting mechanism that lets the deck float over uneven ground, and fine grass dust seizes that mechanism so the mower reports a fault even when the blades look clear. With the debris cleared, press the deck up and down by hand and confirm it moves smoothly and springs back. If it is stiff, keep clearing the packed dust around the pivot points until it travels freely.
Check the discs, center nut, and blades
Look at each disc for cracks or wobble, since a loose or cracked disc throws the balance and trips the motor. Confirm the center nut or collar holding each disc is snug. Each disc holds three blades on small screws you remove with a 2.5mm Allen key; replace blades that are dull, bent, or have worn screw holes, and make sure new blades pivot freely on their screws rather than binding.
Look for a wound obstruction on the disc shafts
String, wire, trimmer line, or thick weed stems can wrap around a disc shaft and lock it. Turn each disc slowly by hand and watch for something wound at its base, then cut it away. A single wrap of line around a shaft stops that disc and makes the mower report the blade motor as stalled, which looks alarming but clears in a minute once the wrap is gone.
Restart, and if it persists suspect the sensor
Set the mower upright, power on, and run a short mow to confirm the discs spin. If it still errors immediately with everything clean and free, the lifting-mechanism sensor or a blade motor may have failed rather than being clogged. Note the exact error text shown in the Mammotion app and give it to Mammotion support, since a clean mower that still throws a cutting error points at a sensor.
Quick Solutions
Still having issues? This is usually the deeper cause below.
If the sensor still misses events after repositioning, check whether a scheduled 'home' or 'away' mode is overriding the sensitivity setting silently.
Make clearing under the blade deck part of routine maintenance every few weeks in the growing season, since the lifting mechanism seizing on packed grass is the number one cause of a Luba that stops cutting. Mammotion has a support portal with Luba articles at support.mammotion.com.
This issue almost always looks more complex than it is — the majority of cases trace back to a single setting, a stale credential, or a default that shipped wrong.
- Wet grass packed under the discs and guards
- Seized floating cutting deck from packed grass dust
- Loose or cracked blade disc throwing the balance off
- Loose center nut on the disc collar
- String or wire wound around a disc shaft
Before you go — try one of these (they fix most cases).
Official Manufacturer Manual
Mammotion provides official product documentation through their online manual rather than downloadable PDF. Access setup guides, troubleshooting steps, and product specifications for your Mammotion Luba Robotic Lawn Mower.
Source: mammotion.com
Need More Help? Mammotion Support
Note: The contact information below connects you directly to Mammotion's official customer support team, not Trunetto. They can help with warranty claims, device replacements, and advanced technical issues.
Accessories owners commonly pair with Mammotion Luba Robotic Lawn Mower.
Blink Mini - Compact indoor plug-in smart security camera...
Blink Mini - Compact indoor plug-in smart security camera...
Blink Mini - Compact indoor plug-in smart security camera...
As an Amazon Associate we earn from qualifying purchases.