Joyce Machine Screw Jacks - Manual (Page 5)

5
2-2 Repair Parts
Obtain repair parts by calling Joyce/Dayton Customer Service at (800) 523-5204, (937) 294-
6261, (937) 297-7371 (facsimile) or by email
[email protected] . You may also call
your local sales representative. When ordering repair parts, please supply the serial
number (located on the jack nameplate).
Recommended repair parts for rebuild or spares. Refer to Section 3-1 Exploded View and
Section 3-2 Parts List.
A. (1) Thrust bearing – Item 4
B. (1) Worm gear – Item 5
C. (2) Worm shaft bearing and race – Item 6
D. (2) Worm shaft seal – Item 7 (2-ton and larger)
E. (1) Shim kit – Assortment of item 8
F. (1) Worm - 12
G. (1) Lifting screw - 14
H. (1) Boot (if signs of wear are evident) – Item 34
I.
(1) Traveling Nut - 37
2-3 Disassembly of Machine Screw Jacks
Use the appropriate disassembly procedure – if the lifting nut is outside the jack on the
screw, the jack is a Keyed for Traveling Nut (KFTN), also called a “rotating screw”,
otherwise the jack is a translating model. Handle machined parts with care, and maintain
an “order of disassembly” to aid in re-assembly. Remove all couplings, screw support
bearings, etc. before beginning disassembly.
Disassembly Procedure for KFTN (rotating screw) Models: see Figure 3-1
1. Remove the boot clamps (item 33) and collapse boots (item 34), if the jack is equipped
with boots. Remove the traveling nut (item 37) from the screw.
2. Loosen the (4) set screws (item 13) in the sleeve cap and remove the sleeve cap by
rotating counter-clockwise (CCW.)
3. The screw assembly can now be removed from the jack sleeve. The screw assembly
consists of the machine screw (item 14), the upper thrust bearing (item 4), the key
(item 38) and the wormgear (item 5). The upper thrust bearing can be removed from
the assembly. The wormgear can be pressed off the screw for replacement if
necessary. Note: On inverted KFTN models, it may be necessary to remove the screw
first.
4. Remove screws (item 10) from the bearing cap (item 3). Remove the bearing caps and
seals (item 7) carefully to avoid damaging seals. Make sure keys have been removed
first. Note: the WJ250 thru WJ51 jacks have retaining clips (item 20) instead of bearing
caps.
5. Carefully remove the shims (item 8) from the jack sleeve or bearing cap. NOTE: there
will not necessarily be an equal quantity of shims per side. Keep track of the number
and order of shims on each side of the jack. The WJ250 thru WJ51 jacks do not have
shims.
6. Remove the worm bearings (item 6). The cup may be press-fit and require the use of a
dead-blow, plastic or other non-marring mallet to remove the worm (item 12).
Disassembly Procedure for Translating Models: see Figure 3-1
1. Remove the boot clamps (item 33) and collapse the boot (item 34) if equipped. On
upright and inverted models, loosen the (4) set screws (item 13) and remove the sleeve
cap (item 2) by rotating CCW.
2. Remove the protection tube (item 11) and check to see if the lifting screw has travel
stops. This may require the use of a pipe wrench or strap wrench. If the jack has travel