means for directing said {HEAD ~ intermingled oil} and coolant back to said {TAIL ~ coolant tank} 
back to
means for directing said { HEAD ~ intermingled oil } and coolant back to said { TAIL ~ coolant tank }
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL OTH TAIL TAIL TAIL TAIL TAIL TAIL