5
1. Tag critical parts to facilitate reassembly.
2. Mark mating surfaces to ensure proper meshing.
3. Clean and lubricate all parts as required.
4. All seals must be replaced when rebuilding.
5. All screws, washers and other small common parts
must be replaced if damaged in any way.
6. Replace damaged or frozen lubrication fittings with new ones.
2-3 Required Tools
A bearing puller or press, and common hand tools are
necessary for proper assembly and disassembly.
2-4. Disassembly (Refer to Figure 3-1)
1. Remove lifting screw (19) from actuator.
2. Remove bottom pipe (16) from shell (1) (upright models) or
shell cap (4) (inverted models) or base plate as applicable.
3. Loosen and remove set screws (14) in cap (4) and
remove cap from shell (1).
NOTE
It may be necessary to break shell cap or base plate loose
with a hammer.
4. Remove worm gear (3) from shell (1).
5. Remove top load bearing (2) which may be attached to
either shell cap (4) or worm gear (3).
NOTE
Use only a soft face hammer to tap bearings loose.
6. Remove bottom load bearing (2) which may be attached
to either the shell (1) base plate or worm gear (3).
7. Remove four cap screws (5) from each of the two worm
flanges (8) and remove flanges.
NOTE
Be careful not to lose flange shims (9 and 10).
8. Press oil seal (7) out of flange (8).
9. Remove worm (12) and worm bearings (11) from shell (1)
by striking one end of worm with a soft face hammer.
10. Remove worm bearings (15) from worm (14) with
bearing puller or press. Note: This step will not be
necessary if worm or worm bearings are not damaged.
2-5. Cleaning
1. Use degreasing solvent to remove grease or oil from all parts.
NOTE
Remove grease from unit and do not reuse old grease.
CAUTION
Provide adequate ventilation during the use of cleaning
agents; avoid prolonged breathing of fumes and contact
with skin.
2. Use clean hot water or a soap solution for general
cleaning of painted surfaces.
3. Dry parts thoroughly after cleaning.
NOTE
Remove grease from unit and do not reuse old grease.
2-6. Inspection (Refer to Figure 3-1)
Inspect actuator parts as follows:
1. Make a visual inspection of shell (1) for broken, cracked
or distorted areas. Check threads of all bores for burrs
or broken threads.
2. Check shell cap (4), base plate, bottom pipe (16), lifting
screw (19), worm gear (3) for burrs or scratches on
their working or mating surfaces.
3. Check fit between lifting screw thread and internal
thread in worm gear. If fit is excessively loose, replace
worm gear or lifting screw as required.
4. Check small common components (screws, etc.) and
replace as required.
5. Check bearings (2) and (11) for seizure, galling or play
and replace as required.
2-7. Assembly (Refer to Figure 3-1)
1. Press worm bearings (11) onto worm shaft (12) making
sure that bearings are seated properly against shoulder.
NOTE
When tapered roller bearings are used, the small end of
the cone should point to the worm end.
2. Position worm shaft end (12) in shell (1).
NOTE
If tapered roller bearings are used, tap worm bearing cups
into place in the shell.
3. Press oil seals (7) into worm flange (8).
NOTE
The sealing element should point inward.
4. Position worm flanges (8) with shims (9 and 10) and
bolt in place.
5. Position bottom load bearing (2) or bearing cup in shell (1).
5a. Press load bearing cones onto worm gear (3).
6. Install worm gear (3) in shell (1).
