6 Maintenance
22
Read the instructions carefully. The items refer to the parts list and service kits section.
Drawings 14-17
Gear Box Internal Assembly
Caution: If you suspect that the Gear Box requires service, proceed with caution. If at any time you do
not feel completely comfortable servicing the Gear Box, contact Alfa Laval immediately.
Drawing 14: Begin by holding the Gear Box upright to keep the internal components from unexpectedly spilling out.
Use a pick to remove the upper Gear Box Snap Ring (pos. 16.2) from the top of the Planetary Ring Gear (pos. 16.1).
Hold the Top Planetary Washer (pos. 16.3) in place on top of the Gear Stack (Drawing 15) and flip the Ring Gear and its
contents upside down.
Press down gently on the Planetary Output Shaft (pos. 16.8.1) so that the Gear Stack (Drawing 15) slides down and out of the
Ring Gear.
Remove the lower Gear Box Snap Ring (pos. 16.2) from the bottom of the Ring Gear, then remove the Planetary Output Shaft
Washer (pos. 16.9). Inspect the Washer for scoring or cupping and replace if necessary.
Drawing 15: Separate the four layers of the Gear Stack (Drawings 16 and 17) and place the layers on a flat surface.
At the top of the gear stack is the Top Planetary Large Washer (pos. 16.3). Inspect the Washer for scoring or cupping and
replace if necessary.
Beneath each of the three upper Gear Stack layers (Drawing 16) is an Inter-Tier Planetary Washer (pos. 16.7). Inspect these
washers for scoring or cupping and replace if necessary.
Drawing 16: The upper three layers of the Gear Stack are identical. Each layer includes four Planet Gears (pos. 16.4.1) with
pressed-in Planet Gear Bushings (pos. 16.4.2); one Planet Carrier Plate (pos. 16.6.1) with a Planet Gear Pinion (pos. 16.6.2)
pressed into the bottom and four Planet Gear Idler Shafts (pos. 16.6.3) pressed into the top. Four Planet Gear Washers (pos.
16.5) sit on the Idler Shafts underneath the Planet Gears.
Inspect the Gear Bushings for severe wear on the top or bottom; overly loose fit inside the Planet Gears; or overly loose fit on
the Idler Shafts. The Bushings do not need to fit tightly into the Planet Gears for the Gear Train to run properly.
Inspect the Gear Pinion (pos. 16.6.2) for worn, damaged, or sharp/pointed teeth. Pay special attention to the Pinion in the
lowermost layer, as it experiences the most torque. Ensure that the Pinion is fully pressed into the Carrier Plate and does not
shift or rotate.
Inspect the teeth of the Planet Gears (pos. 16.4.1) for any worn, broken, or bent teeth.
Ensure that the Idler Shafts are tightly installed in the Carrier Plate and are pressed all the way into their respective holes.
Inspect the Gear Washers for scoring or cupping and replace if necessary.
Drawing 17: The lowermost layer of the Gear Stack is the same as the upper layers, with the exception that the Carrier Plate
and Gear Pinion are replaced with the Planetary Output Shaft (pos. 16.8.1). Inspect the Gears (pos. 16.4.1), Gear Bushings
(pos. 16.4.2), Gear Washers (pos. 16.5), and Idler Shafts (pos. 16.8.2) as described above.
Inspect the Planetary Output Shaft for wear or damage on the shaft.