The housing hub 68 and the primary flange 21 define a passage 70 which opens into {TAIL ~ a space} 56 at the radially inner end of the primary flange and a chamber 57 at the radially outer end of {HEAD ~ the primary flange} 
The housing hub 68 and the primary flange 21 define a passage 70 which opens into { TAIL ~ a space } 56 at the radially inner end of the primary flange and a chamber 57 at the radially outer end of { HEAD ~ the primary flange }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD