Clack V3728 WS2 drive cap assembly
Clack

Clack WS2 Drive Cap Assembly (V3728)

Product Code V3728

$82.52
Clack Corporation · Genuine OEM

WS2 Drive Cap Assembly

Couples the WS2 drive train to the piston, moving it precisely through every service and regeneration position.
Part # V3728Clack WS2 (2")Genuine Clack

The Clack V3728 drive cap assembly sits at the top of the WS2 valve body. It carries the gearing that the piston rod attaches to, turning the motor's rotation into the straight-line piston travel that steps the valve through service, backwash, brine draw, rinse and refill. A cracked cap or stripped gear leaves the piston stuck between positions — replacing the full assembly gets the valve cycling correctly again.

At a Glance

Key Specs

Part Number
V3728
Fits Valve
Clack WS2
Port Size
2"
Type
OEM Assembly
Specifications

Technical Details

Manufacturer Clack Corporation
Manufacturer Part # V3728
Description WS2 drive cap assembly
Compatible Valve Clack WS2 series 2" control valves
Function Drives the piston between valve cycle positions
Condition New, genuine Clack part
Why Replace It

Signs of a Failed Drive Cap

Stuck Regeneration

The valve hums or shows an error but never reaches the next cycle position.

Grinding or Clicking

Stripped or broken gear teeth slip under load instead of moving the piston.

Leak at the Cap

A cracked cap or failed seal lets water weep out around the top of the valve body.

Installation

Replacement Overview

  1. Put the valve in bypass, unplug power, and relieve pressure by opening a downstream faucet.
  2. Remove the valve cover and the drive bracket and motor assembly to expose the drive cap.
  3. Unscrew the drive cap assembly and lift it out together with the piston.
  4. Transfer the piston to the new V3728 cap, lubricate the cap O-ring with NSF-approved silicone grease, and thread it back into the valve body.
  5. Reinstall the drive bracket, motor and cover, restore power, and run a manual regeneration to confirm the valve steps through every cycle.

🔧 Pro Tip: With the cap off, the piston and seal stack are fully exposed — it's the ideal time to inspect them. We stock the matching WS2 seal & spacer stack (V3729), downflow piston (V3725) and brine piston (V3726).

Compatibility

Will It Fit My Valve?

The V3728 is built for Clack WS2 series 2" control valves. It does not fit Clack WS1, WS1.25 or WS1.5 valves, which use a different drive cap. Check the model on your valve's label before ordering, or call us and we'll confirm the right part.

Ships from California

Fast dispatch from our Santa Ana, CA warehouse.

Genuine Clack

Factory OEM part, not an aftermarket copy.

Build Help

Questions on your valve? Call (877) 541-6603.