School me on the Anti drainback valve in the filter

[Blown7]

As the Subject line says what is the purpose and the need for the valve in the filter? If the filter is mounted vertically whats the point? The reason I ask is my aircraft filters do not contain them and the filters 90 percent of the time are mounted on the engine horizontally allowing the oil in the filter to drain back. My Hamburger dual filter remote mount in a vertical install and I would like to use my Champion ch 48111-1 filters for this application on the 401. They are rated for 40 micron with 15 gallons of flow per minute with a 550 PSI burst rating with no internal bypass.

Jeff

[jeepsr4ever]

Jeff all it is only a small rubber diaphram that covers the outer edge of the filter. At least thats how I have seen it. What it tries to do is hold any backpressure by creating a seal so the volume in the oil pan doesnt try to suck the oil from the filter and gallies back to the pan by gravity.