2-50. R.O. PUMP MOTOR SHEAVE ASSEMBLY.
a. General. The R.O. pump motor sheave holds the five Vbelts that transmit power to the R.O. Pump. This
paragraph describes removal, inspection, cleaning, and installation of the pump motor sheave.
b. Removal. (Figure 2-52)
(1) Remove R.O. pump belt shroud in accordance with paragraph 2-75.
(2) Remove R.O. pump belts in accordance with paragraph 2-76.
(3) Remove three bolts (2) and three lockwashers (3) from hub (1) and sheave (4).
(4) Remove pump motor sheave (4) from hub (1).
(5) Loosen, but do not remove, setscrew in hub (1).
(6) Using puller, remove hub (1) from pump motor shaft (6).
(7) Remove shaft key (5) from pump motor shaft (6).
(1) Remove grease and dirt from sheave, hub, and hardware.
(2) Remove rust and corrosion from the entire R.O. pump motor sheave assembly.
(1) Inspect sheave for cracks, dents, excessive wear by belts, or other damage.
(2) Inspect hub for cracks, stripped thread holes, or other damage.
(3) Inspect bolt heads and threads.
(4) Inspect lockwashers for offset ends.
e. Repair or Replace.
(1) Replace damaged pump motor sheave.
(2) Replace damaged or worn hub.
(3) Replace all damaged screws, nuts, bolts, and washers.
f. Installation. (Figure 2-52 and Figure 253)
(1) Insert shaft key (5) into keyway of pump motor shaft (6). Align with front of shaft (figure 2-53).
(2) Place sheave (4) on hub (1) and attach with three lockwashers (3) and three bolts (2).
(3) Press hub (1) (figure 2-52) onto shaft (6) and align motor sheave with pump sheave within 0.06 inch
(1 .52 mm) with a straight edge (figure 2-53).
(4) Tighten setscrew on hub (1) into key.
(5) Replace drive belts in accordance with paragraph 2-76.
(6) Recheck alignment of both sheaves.
(7) Replace R.O. pump belt shroud in accordance with paragraph 2-75.