Before you pull the valve (which is usually a pain on top mount filters), post the make / model of your pump. Note the the number on the electric motor are ONLY for the motor, and not the pump. Pump info is on the 'wet' part of the case.

The reason is, if your pump is oversized for your filter, the solution may be to throttle your pump back. There are several ways to do this.

It would also help if you can post pictures, by linking from Flickr, Photobucket, Picasa or by emailing them to poolforum@gmail.com