JLG 450A_AJ Series II Service Manual - Manual (Page 89)

SECTION 3 - CHASSIS & TURNTABLE
3121290 – JLG Lift – 3-49
5. Remove thrust bearing (11) from top of coupling shaft
(12). Inspect for wear, brinelling, corrosion, and missing
rollers.
6. Check exposed portion of coupling shaft (12) for signs of
rust and corrosion which might prevent its withdrawal
through seal and bearing. Use crocus cloth or fine emery
paper as needed.
7. Remove coupling shaft (12), by pushing on output end
of shaft. Inspect coupling shaft bearing and seal sur-
faces for spalling, nicks, grooves, severe wear or corro-
sion and discoloration. Inspect for damaged or worn
internal and external splines or keyway. Replace shaft if
any of these conditions exist.
NOTE: Minor shaft wear in seal area is permissible. If wear exceeds
0.020" (0.51 mm) diametrically, replace coupling shaft. A
slight “polish” is permissible in shaft bearing areas. Any-
thing more requires coupling shaft replacement.
8. Remove and discard seal ring (4) from housing (18).