TM 5-4210-233-14&P-2
6-6. FIRE PUMP - Continued
(4) If inspection shows that the wear ring clearances are excessive, or the impeller hubs are scored or
grooved, turn impeller hubs in a lathe to an acceptable rework dimension at which they will clean up
and install undersize wear rings during reassembly. These repair rings are available in 0.025, 0.050,
and 0.075 inch (.635, 1.27, and 1.905 mm) undersize. Table A gives the original hub dimensions for
the impeller and the rework dimensions for each degree of undersize.
TABLE A
IMPELLER AND WEAR RING REPAIR DIMENSIONS
Impeller
Original
Original Wear
Reworked Hub Dia
Undersize Wear
No.
Hub Dia.
Ring No
Ring No.
71800-25
71799
5.501"/5.498 "
71800
5.475"/5.473
71800-50
(139.72/139.65 mm)
(139.06/139.01 mm)
71800-75
5.451 "/5.448")
(138.45/138.38 mm)
5.426"/4.423"
(137.82/137.74 mm)
i. Assembly of Pump Body.
(1) Install impeller (11) and snap rings (13). Make sure snap rings (13) are securely seated at the
impeller hubs.
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