User Guide

Removal of Mounting Bracket from Valve

Body

If it is necessary to remove the mounting bracket from the

valve body, remove stem sleeve, indicator plate, locking nut

and packing nut. Then remove bracket nut. (See Figure 3).

2. Remove actuator piston sleeve. Slide (2) large washers

(1-1/4" O.D. x 9/16" I.D. X 1/8" thick) over the actuator

shaft and screw a 1/2"-20 thread hex nut against the

washers.

3. Tighten the nut (5 turns) until the actuator shaft has been

pulled (compressing the actuator springs) approximately

1/4".

Caution:

Do not remove this retaining nut until reassembly

is completed. Strong spring forces are present.

4. Remove upper and middle housing, bolts and

diaphragms as required. (See Figure 4).

5. Install replacement diaphragms in reverse order. Be sure

diaphragm ribs fit properly in the actuator cover grooves.

6. Reassemble housing and remove retaining nut and

washer on the actuator shaft.

Caution:

Make certain that housing bolts are securely

tightened prior to removal of retaining nut on actuator shaft.

7. Reassemble the actuator to the mounting bracket using

mounting bolts supplied. Spacers (2) are required on

MK-8900 series actuators.

Actuator Springs: Not field replaceable. Return actuator to

factory for service.

MAINTENANCE

This is a quality product. Regular maintenance of the total

system is recommended to assure sustained optimum

performance.