Dolphin wheel not turning

dolphin

Double-check before purchasing

Drive belt access procedure and wheel assembly removal varies between Dolphin model generations — consult your model-specific manual.

The Problem

When one or both wheels on a Dolphin stop turning, the robot loses drive on that side and will either move in circles, fail to move at all, or get stuck. The cause is almost always mechanical: debris jammed in the wheel, a broken drive belt, or a failing motor.

Steps

1
Remove the robot from the pool and flip it over. Spin each wheel by hand — they should rotate smoothly with little resistance.
2
Look for debris jammed in the wheel housing or wrapped around the axle. Use a narrow tool to clear it.
3
Inspect the drive belt connected to the affected wheel. Replace if broken, cracked, or loose.
💡 Keep a spare belt on hand — they are inexpensive and the most common cause of a wheel stopping.
4
Spin the wheel by hand again after removing any debris. It should turn freely. If it grinds or is stiff, the bearings may be worn.
5
Run the robot briefly on a wet surface and observe both wheels. If one spins significantly slower than the other, a motor issue may be present.
6
If the belt is good, the wheel clears freely, and the wheel still does not turn during operation, contact Maytronics support — motor diagnosis is required.

Possible Causes & Solutions

common

Debris — stones, leaves, or hair — jammed in the wheel or axle

Flip the robot and spin each wheel by hand. If one has resistance, look for debris lodged around the axle or in the wheel housing. Use a screwdriver handle or narrow tool to dislodge it.

common

Drive belt broken or slipped off the pulley

A snapped or de-tensioned drive belt means the wheel receives no drive from the motor. Inspect the belt by removing the side panel or wheel cover — replace if broken or slack.

occasional

Worn wheel bearings creating excessive friction

Wheels that spin freely when the robot is out of the water but lock up under the load of the pool may have worn bearings. Replace the wheel assembly if bearings are seized.

rare

Drive motor for that wheel has failed

If the belt is intact, the wheel spins freely by hand, and there is no debris blockage, the motor driving that wheel may have failed. This requires professional service.

When to Replace

Replace drive belts when cracked, stretched, or broken. Replace wheel assemblies when bearings are worn. Motor replacement requires a Maytronics service centre.

Where to Buy

Find compatible replacement parts from these retailers:

Check price for dolphin replacement parts on Amazon

Compatible Parts

Drive Belt Kit

Model-specific. Confirm compatibility with your Dolphin model (E10, M400, M600, Nautilus CC) before ordering.

Dolphin Wheel Assembly

Available as a complete assembly including bearings. Confirm compatibility before ordering.

Frequently Asked Questions

Can I run the robot with one wheel not turning?

No. A robot with one non-turning wheel will drive in circles and miss most of the pool. Fix the wheel issue before using the robot again.

How do I know if it is the belt or the motor?

Spin the wheel by hand with the robot out of the pool. If the wheel turns freely and the belt looks intact, the motor is the likely suspect. If the wheel is stiff or the belt is broken, start there.