Originally Posted By: Gary Allan
There are two series of holes on the baseplate. The outer ring is positioned over the exterior of the filter media. The inner holes are positioned over the interior of the media They're both exposed to the incoming oil flow, and therefore the pressure seen on the exterior of the media. If the PSID exceeds limits, the inner area of the combo valve gets depressed and vents excess flow to the interior of the media.
Low PSID, the ADBV area of the combo valve gets all the flow
Too high a PSID, the inner - bypass part of the combo valve allows flow to go that way.
Pretty trick in concept ..and hasn't shown to be a issue in terms of reliability. I wish that they had a silicon version.
Ah, I see exactly how it works now.