O ring 109 seals against {TAIL ~ fluid leakage} between {HEAD ~ retainer plate} 104 and rear cover 89 
O ring 109 seals against { TAIL ~ fluid leakage } between { HEAD ~ retainer plate } 104 and rear cover 89
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH