Service manual

5
NOTE: If intermediate flange (5) will not slide easily off shaft (6), clamp square housing (4) in a vise with
intermediate flange (5) free. Insert prying device between intermediate flange (5) and square housing
(4). Pry gap until intermediate flange (5) is free to slide off shaft.
CAUTION
ATTENTION
Take care not to damage either faces that are being pried against or 0-ring (41) with prying device.
CAUTION
ATTENTION
If intermediate flange (5) will not slide off easily because its sleeve bushing (53) was seized
on shaft (6), ball bearing (31) was most likely damaged and must be replaced. If intermediate
flange (5) did not slide off easily because it was stuck on housing (4) rabbitt, ball bearing (31)
may not have to be replaced.
12. Remove O-ring (41).
CAUTION
ATTENTION
In next step, ring gear (12), pinion (11) and key (13) will be removed. If ring (12) and pinion
(11) are to be reused, identify them, with a marker or the like, so it can be determined to which
housing they belong (if there is more than one housing in pump) and which direction face of
each gear was positioned in housing. Do not mark with scribe or punch as this may leave a
burr or high spot which could lead to pump damage or seizure. If key (13) is to be reused,
mark it so that it can be assembled into its original stage and facing its original direction.
13. Remove pinion gear (11) and key (13) from shaft (6) and ring gear (12) from front pump square housing
(4).
CAUTION
ATTENTION
If pinion gear (11) will not slide easily off shaft (6), its key (13) is most likely at least partially
sheared. In this case, the disassembly cannot be completed in the field without the chance of
damaging other good parts, and the unit should be returned to Imo for further disassembly
and
inspection.
NOTE: If ring gear (12) will not come out of housing (4), it is most likely seized on its OD and will not be possible to
remove. The pump can still be disassembled with the ring gear (12) left in housing (4).
14. Remove square housing (4) from shaft (6). Do not permit dowel pin (37) to drop as square housing (4) is
removed. Remove dowel pin (37) from either square housing (4) or front flange (2), whichever is
applicable. Remove O-ring (40).
NOTE: If square gear housing (4) will not slide easily off shaft (6), clamp it in a vice with the front flange (2)
free. With a soft-headed hammer, tap on gear end of shaft (6) until there is sufficient gap to insert a
wedging device between the square housing (4) and the front flange (2). Pry the gap until square housing
(4) is free to slide off shaft (6).
CAUTION
ATTENTION
Take care not to damage either faces that are being pried against or 0-ring (10) with prying device.
CAUTION
ATTENTION
If the shaft had to be hammered to remove the square gear housing (4), the ball bearing (31)
was
damaged and must be replaced.
NOTE: If square housing (4) cannot be removed without applying excessive force, unit should be returned to
Imo for further disassembly and inspection.
15. Remove capscrews (42) from seal housing (9).
16. Remove shaft (6) from front flange (2). Removal of shaft also removes seal housing (9), outside lip seals
(32), ball bearing (31), and bearing retaining ring (33).