Dolphin pool robot moving in circles

dolphin

Double-check before purchasing

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

The Problem

A Dolphin that drives in circles instead of covering the full pool almost always has uneven traction or drive power between the left and right sides. Start by checking for jammed tracks and debris before assuming a motor failure.

Steps

1
Remove the robot from the pool and flip it over. Spin each track or wheel by hand and check for resistance or objects wedged in the treads.
2
Inspect both drive belts. Replace any belt that is cracked, stretched, or has lost tension.
💡 Keep a spare belt on hand — they are inexpensive and a common cause of uneven movement.
3
Lay the full cable out straight on the deck and check for tight kinks or permanent coils that could drag during operation.
4
Open the side panels and clear both impeller cavities of any debris.
5
Run the robot briefly on a flat wet surface and observe whether both tracks spin at the same speed.
6
If one track is clearly slower and all mechanical components look fine, contact Maytronics support — a drive motor replacement may be needed.

Possible Causes & Solutions

common

Debris jammed in one track or wheel

Flip the robot and spin each track by hand. Remove any debris, hair, or stones caught in the treads on either side.

common

Worn or broken drive belt on one side

Inspect both drive belts for cracks, stretching, or breakage. A belt that has lost tension on one side will cause the robot to curve toward that side.

occasional

Tangled or kinked power cable creating drag

Lay the cable out straight on the deck before each use. A tightly coiled or kinked cable creates drag on one side, pulling the robot off its cleaning path.

occasional

Clogged impeller on one side

Open the side panels and clear leaves, hair, or buildup from both impellers. Uneven flow between sides can affect drive direction on some models.

rare

Failing drive motor on one side

Run the robot briefly out of the pool and watch both tracks. If one spins noticeably slower, the motor on that side may be failing and needs replacement.

When to Replace

Replace drive belts when cracked or stretched. Replace a failed drive motor through a Maytronics service centre — it is not a DIY repair on most models.

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.

Frequently Asked Questions

Can a tangled cable make my Dolphin drive in circles?

Yes. A heavily kinked or coiled cable creates drag on one side of the robot, pulling it into a curve. Lay the cable flat in the sun for 30 minutes before your next run to relax the coils.

How do I know if a drive motor is failing?

Flip the robot over and run it briefly. If one track spins noticeably slower or not at all while the other runs normally, the motor on the slower side is likely failing.