ARB RD90 - Manual (Page 21)

3 Installing the Air Locker
19
3.7 A B Drilling & Tapping the Bulkhead Port
A port must be drilled and tapped through the differential housing to
allow the seal housing tube through the housing to connect with the
air line from the air compressor.
c Remove the Air Locker from the housing.
3.7.1 A Front Access Housing Port Location
c Mark a spot on the top of the outside shell of the differential
housing in the position shown in Figure 11. The location should be
about 45mm [1.75”] from the gasket face of the cover flange and
very close to the teeth of the ring gear inside.
Figure 11.
c Cover the drive pinion and bearing seat areas with rags to protect
them from metal filings.
c Drill through the housing square to the outside surface using a
11.2mm [7/16”] drill.
c Tap the hole from the outside using a ¼” NPT pipe tap.
c Remove any sharp edges from the hole that may chip-off and fall
into the housing.
c Carefully remove the rags and inspect with a service light inside the
housing to insure no metal filings are left behind.
3.7.2 B Clamshell Housing Port Location
c Mark a spot on the inside of the shallow half of the clamshell
(i.e., as close to the center of the housing as possible) that is in the
same location as the bulkhead port position shown in the
photograph in Figure 12.