After two years of constant use my Polaris 360 just stopped moving. We had recently had a storm and the swimming pool bottom was covered with debris from the trees. The Polaris had been running around the bottom of the pool around thirty minutes before with no problem now it had just stopped. I checked the obvious things, such as, the screen on the inlet hose and it was clear and the water pressure was up to where it should be.
I decided to pull the 360 out of the water and investigate the problem further. As soon as I got it out the problem was obvious. Both wheels on the right side were jammed solid the single wheel move somewhat but there was definitely a resistance on it keeping it from turning smoothly. I removed the top of the Polaris 360 and found that the main drive belt had stretched and slipped off of the pulley. It somehow wrapped itself up around the drive gears jamming them.
All I had to do was replace the belt and it has been working fine ever since. The procedure for replacing the belt is tricky only because you have to remove the wheels from the axle and then slip the axle out to be able to get the old belt out. Installing the new belt is exactly the reverse order of removing the old one.
While you have the Polaris 360 apart it would be a good time to check the wheel bearings for wear. If they show signs of wear and look like they want to separate they should be replaced as well. As the wheel bearings wear out the race that holds the balls in place will slide out and allow the ball bearings to come out in the pool.
There is one more reason that the Polaris 360 will stop moving forward and it has to do with the water jet that turns the impeller that moves the Polaris. The water jet can become clogged if there is no filter in the hose that feeds the Polaris. If a large piece of debris gets into the water jet and can't fit through the jet and be washed out it will plug the jet stopping the forward motion of the Polaris 360.
To get to the jet and clear it take off the top cover of the Polaris and you will see another cover inside on the right side as you look at it head on. Only one screw holds the cover on so remove the screw and lift the cover off. Once the cover is off you will see the impeller and a water jet under neath it attached to a small hose, pull off the end of the hose closest to the water jet and either blow or wash the debris out of the water jet from the outlet side of the jet.
Make sure you get it all out and then re-assemble the Polaris and it should work fine. One more check to make while the Polaris is apart is the water jet that is attached to the "tail," the tail jet can become clogged and cause the Polaris to suck the tail up into the debris bag so it is a good idea to make sure the tail jet is clear as well.
