Fisher 846 - Removing the Pilot;Actuator Assembly; Replacing the Pilot;Actuator Assembly

Instruction Manual
D102005X012
846 Transducer
June 2017
39
Removing the Pilot/Actuator Assembly
To remove the pilot/actuator assembly, disengage the four mounting screws, and gently pull the assembly out of the
module subassembly. To aid removal, the pilot/actuator framework may be gently gripped with a pair of pliers.
CAUTION
Do not attempt to remove the pilot/actuator assembly by gripping or pulling on the deflector or nozzles. Doing so could
alter the alignment or disable the deflector/nozzle mechanism.
Inspect the assembly for a buildup of foreign material. The nozzle passageways should be clear, and the deflector
should be clean. The deflector can be cleaned by spraying it with contact cleaner. Clean the nozzles by gently inserting
a wire with a maximum diameter of 0.38 mm (0.015 inches).
D Insert the wire into each nozzle separately from the outside as shown in figure 20.
D Do not try to put the wire through both nozzles simultaneously.
D Do not push the wire on the deflector bar.
CAUTION
Do not apply force to the deflector bar while cleaning the nozzles. Doing so could alter the alignment or disable the
deflector mechanism.
CAUTION
Do not use chlorinated solvents for cleaning the pilot/actuator assembly. The chlorinated solvents will deteriorate the
rubber diaphragm
Figure 20. Cleaning the Nozzles
A6655‐1
DEFLECTOR BAR
WIRE
WIRE
PLASTIC HOUSING
Replacing the Pilot/Actuator Assembly
1. Verify that the rubber diaphragm under the nozzle area is blue for pilot/actuators inserted into a direct action unit,
or red for pilot/actuators inserted into a reverse action unit.