(1) If necessary, remove motor from pump in accordance with paragraph 2-48 and remove pump
assembly from stand in accordance with paragraph 271.
The chemical feed pump is a delicate piece of equipment. It can
be damaged if dirt or grease gets into the mechanism. Before
beginning disassembly of pump block, make sure work space is
clean and uncluttered. Clean exterior of pump thoroughly before
taking it apart.
Pump blocks are filled with lubricating oil which may spill out of
tie-rod holes. Depending on shop conditions, you may remove
lubrication by opening screw plug on top of each block and
pouring out oil.
(2) Remove two nuts (1) (figure 3-25) (ARMY) from tie rods holding assembly together.
(3) Remove three nuts (1) (figure 3-26) (USMC) from tie rods holding assembly together.
(4) Remove end plate (2) and gaskets (3) from tie rods (5). Discard gaskets (3).
(5) Slide pump block/head assemblies (4) and gaskets (3) off tie rods (5), one at a time.
(1) Clean tie rods, their threads, and threads on nuts holding end plate.
(2) Clean gasket seats before replacing a bad unit with a serviceable one.
(3) Remove chemical corrosion, pitting, and discoloration on each pump unit.
(4) Clean chemical tube couplers on all pump units.