Hayward GMX600NM Valve Clamp Assembly for Pro-Series Top-Mount Sand Filters
The Hayward GMX600NM is the OEM 2-piece valve clamp assembly used to secure a top-mount multiport valve to the filter tank on select Hayward Pro-Series sand filters. If your existing clamp is cracked, warped, stripped, or won’t tighten evenly, replacing the clamp helps restore a tight, stable valve-to-tank connection and can help prevent leaks caused by poor clamp tension.
Fits / Compatibility
- Hayward Pro Series top-mount sand filters including common models such as S166T, S180T, S210T, S230T, and S244T
- Also commonly used on additional Hayward top-mount sand filter families that use this clamp style (verify your filter model and clamp style)
- Frequently paired with Hayward Vari-Flo XL top-mount valves that clamp to the tank (for example, valve assemblies that list GMX600NM as the included clamp)
What It Does
- Clamps the multiport valve securely to the filter tank flange
- Provides even clamping force so the tank O-ring can seal properly
- Helps prevent valve shifting, seepage, and clamp failure from cracked or fatigued plastic
What’s Included
- (2) Black Noryl clamp halves (GM600-NM is commonly molded into each half)
- (2) Bolts (commonly ~2-1/8″ length)
- (2) Nuts
- (2) Rubber end caps (bolt caps)
Note: This clamp secures the valve to the tank. The tank O-ring that seals between the valve and tank is typically a separate part (often referenced as GMX600F on many setups). If you have a leak at the valve-to-tank seam, consider replacing the O-ring at the same time.
Common Reasons to Replace
- Clamp is cracked, split, or sun-brittle
- Clamp won’t tighten evenly or won’t hold tension
- Valve shifts or rocks on the tank flange
- Leak at the valve-to-tank connection due to poor clamping (after confirming the tank O-ring is in good shape)
Installation Notes
- Turn off the pump and relieve filter pressure before loosening any clamp hardware.
- Clean the tank flange and valve mating surfaces so the clamp seats flat and evenly.
- Tighten the clamp hardware evenly to avoid cocking the valve or pinching the O-ring.
- After reassembly, run the system and check carefully for seepage around the clamp seam.
Related Products
- Hayward GMX600NM Valve Clamp (search)
- Hayward GMX600F Tank O-Ring (search)
- Hayward SP071620T Vari-Flo XL Top-Mount Valve (search)
- Hayward Pro Series Sand Filter Parts (search)
- Silicone O-Ring & Gasket Lubricant (search)
Maintenance Tips
- Keep the clamp area clean—grit on the flange or O-ring can cause leaks and uneven clamp tension.
- Do not overtighten to “stop” a leak; replace the tank O-ring if it’s flattened, stretched, or nicked.
- If the valve-to-tank joint seeps after service, depressurize, re-seat the valve evenly, and retighten the clamp uniformly.
- Shade exposed equipment when possible—direct sun accelerates plastic aging.
