The Ford Barn - View Single Post - 90 degree oil filter hits oil return pipe

MikeK · 03-17-2020, 10:58 AM

Several filters other than the big, FL-1A that holds .88 quarts of oil will fit the same side mount:

Fram PH7328, 3 5/8D x 3 1/4 H .6quart
Fram PH3614, 3"D x 3 3/8 H .4quart
Fram PH3600, 3"D x 5"H .6quart

If you're not a Fram fan, look up the conversions to another brand.
All these filters will fit either directly on the side cover in place of the FL1A or on the 90 degree adapters.

There has also been some talk on this forum (different thread) concerning the backflow preventer flaps in oil filters. Almost all spin-on oil filters have a "backflow preventer" rubber flap valve of sorts that keeps the oil from draining in horizontal apps. A 90 degree adapter is NOT needed to keep the filter full, but they prevent a big mess on removal, and allow 100% pre-fill when changing filters on the side cover mounts.

The ONLY call to remove or defeat it would be if you were running one of the secondary bypass type filters which generate no pressure into the filter. If your filter feeds from the typical side cover mount with an internal tube to the pump outlet it has significant positive pressure. Removing the "backflow preventer" is actually a hindrance, as 1) pre-filling and installing a new filter is a big mess when you go to spin it on, and 2) if your filter is horizontal it will drain every time the engine is stopped, requiring the engine to run with no oil output until the filter fills.

03-17-2020, 10:58 AM	#4
MikeK Senior Member Join Date: May 2010 Location: Windy City Posts: 2,919	Re: 90 degree oil filter hits oil return pipe Several filters other than the big, FL-1A that holds .88 quarts of oil will fit the same side mount: Fram PH7328, 3 5/8D x 3 1/4 H .6quart Fram PH3614, 3"D x 3 3/8 H .4quart Fram PH3600, 3"D x 5"H .6quart If you're not a Fram fan, look up the conversions to another brand. All these filters will fit either directly on the side cover in place of the FL1A or on the 90 degree adapters. There has also been some talk on this forum (different thread) concerning the backflow preventer flaps in oil filters. Almost all spin-on oil filters have a "backflow preventer" rubber flap valve of sorts that keeps the oil from draining in horizontal apps. A 90 degree adapter is NOT needed to keep the filter full, but they prevent a big mess on removal, and allow 100% pre-fill when changing filters on the side cover mounts. The ONLY call to remove or defeat it would be if you were running one of the secondary bypass type filters which generate no pressure into the filter. If your filter feeds from the typical side cover mount with an internal tube to the pump outlet it has significant positive pressure. Removing the "backflow preventer" is actually a hindrance, as 1) pre-filling and installing a new filter is a big mess when you go to spin it on, and 2) if your filter is horizontal it will drain every time the engine is stopped, requiring the engine to run with no oil output until the filter fills.