Hayward C1200 Stripped Locking Knob/Rod Fix


New member
Aug 24, 2019
Moved from here.

filter has one year warranty. seen similar models where the tightening rod loosen from the bottom debris sump (usually from overtightening and/or lack of top lid O ring lubrication?) rod is probably intact so either the bottom or top female threads may be messed up. if under warranty, Hayward will replace with new filter. if not you could order replacement locking knob and use dremel tool to surgically remove current locking knob from rod assuming knob is stripped. if sump base is stripped, i'm not aware of a repair other than replacement of filter.
The stripped threads in the base of a Hayward Starclear pool filter can be fixed with a Helicoil, part 5521-9. About $35 on eBay. The kit comes with a tap, a stainless insert with new threads and a tool to install it. You are supposed to use a 19/32 drill, but I didn't need one; the hole was big enough I could just use the tap. I used a 1/2" 12 point socket and a long extension to turn the tap, since its so far down in the filter base. It's a 10 minute repair. The threads on the rod are 9/16, UNC 12 threads per inch.