Valves (Shower & Bath)

Please refer to the following steps below to service your Kohler Rite-Temp K-304 shower valve with the mixer cap GP77759 and pressure balancing unit (PBU) (GP500520) or the mixer cap and PBU kit (GP76851).

CAUTION: Before doing any repairs to your Kohler valve, please shut off your water.

1.
Remove the two screws.

2.
Remove the collar (sometimes it may not be present).

3.
Note: If replacing the mixer cap with a new one, use the metal collar (Fig. 3) included with your replacement:

Unless the new valve has the new style collar:

4.
Remove the cap assembly.

5.
Remove the pressure balancing unit (PBU) using a pliers.

Note: If your mixer cap looks like the below image, replace it with part number GP77759:

1.
Check if the inside of the brass valve body is clean without any debris or burrs. The inside of the brass body should like this when installed.

Note: If there is any debris or brass burrs, clean it out with a 50/50 white vinegar and water solution. To remove burrs, use a Scotch-Brite pad, taking care not to scratch the sealing surface where the PBU seals seat against the ports of the valve body.

2.
Check for small o-rings on the back of the PBU:

3.
Check for large o-rings on the back of the cap assembly:

1.
Apply silicone lubricant on the small o-rings that go on the back of the PBU:

This will hold the o-rings in place while installing the PBU into the valve body. Lubricant does not need to be applied to the large o-rings that install on the bottom of the cap assembly:

2.
Apply lubricant to the larger o-ring around the cap assembly.

Make sure that the tab inside the brass body aligns with the notch cut out on the back of the PBU unit.

The PBU should not be at an angle:

*Incorrect installation

The PBU should be completely horizontal in the valve body:

Note: Do not place the PBU inside the brass body at an angle and rotate it. This will cause the small o-rings in the PBU to move out of position and will cause the valve to leak.

1.
Place the black cap assembly on top of the PBU and press it into the brass body. The black top on the mixer cap should be in the 12 o'clock position. (Fig. 17a, 18a, and 19) show correct installation for the current collar design. (Fig. 17b and 18b) show correct installation for the older collar design.

2.
Place the metal collar over the mixer cap and tighten the screws on the left and right. Note: Do not install the metal collar before the black cap assembly. (Fig. 20a, 21a, and 22) show incorrect installation for the current collar design. (Fig. 20b and 21b) show incorrect installation for the older collar design.