Power Jacks S-Series - Manual (Page 8)

8
Sym-metric Series – Screw Jacks
6.2 Rotating Screw D.A.I.
6.2.1 Main
Unit
6.2.1.1 Ensure that shell cap grub screw and plug (18) are slackened back clear of the thread grip (36) in
shell (1) before unscrewing the shell cap (It may be necessary to tap shell cap loose).
6.2.1.2 On some models it will be necessary to remove the worm shaft (4) before the worm gear assembly
can be pulled clear of the shell.
6.2.1.3 Check all parts for damage or excessive wear and replace where necessary paying special
attention to “O” rings (13) & oil seals (8 & 9).
6.2.1.4 After re-assembly of the worm shaft assembly, strike each end of worm sharply with a wooden or
fibre mallet to seat bearings properly. (Bearings must be assembled with the shield facing
outwards).
6.2.1.5 Press oil seals (9) into worm recesses in shell housing (1) with the sealing members pointing
inwards.
6.2.1.6 When re-assembling the worm gear and load bearings ensure that the bearings are fitted so that
the plate with the smallest bore size fits over the worm gear spigot.
6.2.1.7 The shell cap should be fitted after the worm shaft assembly has been securely clamped and with
the worm gear assembly in position. Tighten the shell cap until a slight drag is felt on rotating the
worm shaft by hand.
6.2.1.8 Tighten shell cap grub screw (18). It may be necessary to fit a new thread grip if it has become
worn due to numerous adjustments.