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Replacing M14 Plunger Packing

To make service easier, it is suggested that several gallons of clean water be pumped through the M14 before any service procedures that involve fluid end components are started. This action will remove a significant portion of contaminants left in the fluid cylinder by the normal pumpage and improve the ability to work with the parts or spot potential problem areas. Refer to the following page for position of parts.
Bleed off all pressure inside pump fluid end before starting any service work. Shut the valve on the inlet piping if provided to prevent flow of liquid from the source into the pump during service. Check to insure that the power is locked out.
Unbolt the plunger clamps (14) and remove them from the plungers (42) and plunger rods (6). Remove the nuts (52) holding the stuffing boxes (37) to the fluid cylinder (34) and remove the stuffing boxes (37).
Rotate the crankshaft (2) by hand until one of the plunger rods (6) is fully retracted from the plunger (42). Slide the plunger and stuffing box out of the cradle of the pump as a single unit. Repeat this procedure for the other two plunger stuffing box assemblies.
Loosen the set screw (55) locking the threads on the adjusting nut (41) and unscrew the adjusting nut. Use caution because the packing (39) is spring loaded. Pull the plunger (42) from the assembly and then remove the packing (39 ).

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Inspect all parts for damage or unusual wear patterns and replace any components that appear damaged. Insure that the plungers are smooth and free of cracks, scores and grooves. New packing will fail prematurely if used with plungers that have damaged or have rough surfaces. FMC Technologies recommends that all three packing sets be replaced, not just those that show signs of leakage, whenever this type of service is performed. This will help insure maximum operation time between service intervals.
Reverse the previous steps to rebuild the pump after worn or damaged components have been replaced. FMC Technologies recommends that all seals or gaskets that are disturbed during a service procedure be replaced. This includes the stuffing box face seal o-ring (45) and valve cover o-rings (44). Insure that all fasteners are tightened to the values specified in the Fastener Torque Requirements section of this manual.