Polaris 65 question

[vlapinta]

My Polaris 65 is not moving properly, it is very slow. I have hd it for 2 years with no problems. I removed the top and the white piston is spinning slowly around the piston is moving very slowly back and forth. I noticed when the white piston inside moves back a little the robot moves but now most of the time it just spins and dosen't move back and forth which causes the robot to sit in one spot. Is is supposed to be moving back and forth quickly or slowly? Anyone have any suggestions what could be wrong? I did make sure the filter near the quick connect wasn't clogged. I am just not sure how fast that piston inside the tube is supposed to be moving. Can this be the problem? The water is shooting out where it is supposed to, so nothing seems glogged. I am getting the idea that to get motion the inside must go back and forth which is not happening.

Vicki