Don Terrill’s Speed-Talk

I am doing a couple of oil drain backs from the heads and i have a remote oil filter with 2 inlets and to outlets can i use one inlet for a return line or will the pressure it back up the line to the head,i only use one inlet and one exit atm or punch a couple holes in the top of the sump.

Oil drainback lines from the heads should be plumbed to the oil pan. DO NOT USE the ports off the oil filter housing.

Mark is correct and you answered your own question.
Your initial idea would plumb a gravity fed line into a pressure fed line.
Yes, it will go the wrong direction and essentially send the pressure to zero.

Also, gravity alone is not enough to push oil through any worthwhile mesh filter.

Thought that may have been the case ,Cheers guys

Will a vacuum pump make the problem worse or help with getting the oil back down to the sump?

Depends. If you suck from a rocker cover, likely worse. If from the valley, better.

MadBill wrote: ↑Sat Oct 05, 2019 12:14 am Depends. If you suck from a rocker cover, likely worse. If from the valley, better.

It pulls from the valve cover now but i will do a fitting on the valley plate.Cheers