"John Horner" wrote in message
news:Wj13j.10154$Mr.6069@trnddc04...
Leon wrote:


This is way off the woodworking topic, but the function of an
anti-drainback valve is to keep the filter full after the engine is shut
down and oil pressure is no longer generated. It is normally a rubber
flap which acts as a one way valve.


You are correct.