ARB RD94 - Manual (Page 15)

4 Installing the Air Locker
13
4.3 Drilling and 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 Mark a spot for the bulkhead port on the left hand (seal housing)
side toward the top of the differential housing that is in an area that
will be well clear of the ring gear, the differential, and any other
obstructions that may snag the seal housing tube (Fig.7.).
HINT : The mark shown in figure 7. should be copied as
closely as possible.
Figure 7.
Figure 8.
c Cover the drive pinion and axle tube areas with a rag to protect
them from metal filings.
c Drill through the housing square to the outside surface using an
11.2mm [7/16”] drill. (Fig.8.)
c Tap the hole from the outside using a ¼’’ NPT tapered pipe thread
tap.
c Remove any sharp edges from the hole that may chip-off and fall
into the housing.
c Very carefully remove rags and inspect with a service light inside
the housing to ensure no metal filings are left behind.