Oil Filter-ology
 

OR converting our oiling system to “full flow” oil filtration. Might get a little wordy but forgive me, I’m old
I wanted to start a discussion of the benefits of converting our engines. There are some threads here and over at the H.AM.B.

After giving it some thought I’ve concluded it’s a waste of time. Here’s why;
The flathead is ALWAYS filtering oil thru the 60-80 .000” restrictor orifice. I use either a WIX or Baldwin. There is other brands out there of similar quality

MOST “modern” engines have a bypass valve to protect the oil filter from over pressurization. Fer instance, that little aluminum gizzy/adaptor where your spin-on filter goes in a Chevy has a little (3/8”) spring loaded disk [valve] that unloads at about 6 lbs. There are others out there that unload at a higher pressure
MOST spin on filters have their own [internal] bypass valves.

Start throwing rocks, guys. I’m here to learn

Re: Oil Filter-ology
 

Gene: The topic of Full flow oil system conversion has been around for a very long time.
Here's a Fordbarn discussion from 2016. No doubt Henry Ford's OEM system was adequate for his OEM engines.
https://www.fordbarn.com/forum/showthread.php?t=203777

Re: Oil Filter-ology
 

Re: Oil Filter-ology
 

I'm with "Gene1949" on this, especially the way the vast majority of these vehicles are used and maintained these days. One thousand mile oil change intervals and no operation on dirt roads means that it is more important to get as many of the smaller particles filtered out as you can and not worry about the big chunks (of which there are none). Someone on here (I think it was "51-Merc-Ct") figured out that all of the oil passes through the filter every 10 or 11 minutes.

Better we should concentrate on fulfilling the 1000 mile interval suggested for chassis lubrication. A lot of people miss it.

Re: Oil Filter-ology
 

In one of the many past threads, someone posted a comment about the “stock ugly oil filter”. I think one in original type condition or re-painted with original style decals looks good sitting up there. I’ve seen some nice ones with pin stripes. As has been stated many times, if it didn’t work Henry would not have spent the money to put it on there......Mark

Re: Oil Filter-ology
 

I also consider the "full flow" system a waste of time.
Spin on filters with "bypass valves" have the valves to insure that the oil continues to flow should the filter clog, not to prevent "over pressurization" in the filter.

Re: Oil Filter-ology
 

51 MERC-CT

I did not mean to suggest the filter internal bypass was to prevent over pressurization. That is the job of the block adaptor as stated in my post.
You are correct in that the oil filter bypass is for those who do 20,000 mile oil changes [clogged filter]
Sorry for the confusion

Re: Oil Filter-ology
 

I converted my '40 pickup to 90% filtration and I would not do it again, not worth the work and expense involved!

Re: Oil Filter-ology
 

my two cents worth i would never run without a filter of some kind the only mod i would make to the ford setup would be to move the restrictor to the return this allows anything larger than the restrictor to enter the filter not clog the restrictor Major heavy engine manufacturers still run bypass filters and if you weigh the filters when you change them surprise surprise the bypass filter has more weight increases so its trapping more than the full flow and dont use cheap filters their cheap for a reason quality counts

Re: Oil Filter-ology
 

They run 3 micron bypass filters in addition to the full flow filter.

Re: Oil Filter-ology
 

Moving restrictor to return line has one disadvantage in that pressure inside filter housing will be somewhat higher. I would like to hear from someone who's done this to see if they had any problems with leakage of canister.

Re: Oil Filter-ology
 

can be done canister needs to be in good condition and top edge lapped flat

Re: Oil Filter-ology
 

Interesting idea, thank you.

Re: Oil Filter-ology
 

I'm with Gene here also. Bypass filter catches smaller particles and does a really good job.
In our OT heavy trucks there is also centrifugal canister filter witch spins by oil pressure.
That is one awesome devise and collects amazing amounts of crap from oil.

Re: Oil Filter-ology
 

I would leave the restrictor in place on the inlet as designed, for one on cold start up I would want all the oil pressure I could get going to the internals rather than filling a drained out oil filter housing. If you have things floating in your engine that would clog a restricter you have other problems. Just my opinion

Re: Oil Filter-ology
 

This is just for information; my 2 CDN 8Ba's with factory filter do not have a restriction on the inlet to the filter; the restriction is downstream of the filter. The restriction is a very small hole drilled in the center shaft which is the return "pipe" to the pan. I guess this would mean the filter would clean the oil before it had a chance to plug the restriction which would not be the case with the restrictor on the inlet. I doubt if the filter would drain down 1/2 a pint when sitting for a long time in which case I would guess the filter itself would act as a restrictor on start-up. Both of these engines had the restrictor hole plugged (with crud) when taken apart, effectively the filter would never get dirty so unlikely it was ever changed. Restriction plugged= no filtering.

Re: Oil Filter-ology
 

US filters have two (2) holes in the center return pipe at the same level as the restricted inlet.
There is no restrictor hole in the inlet to the filter. The restrictor hole is in the fitting that goes into the inlet hole on the filter.




https://www.fordbarn.com/forum/pictu...ictureid=41578

Re: Oil Filter-ology
 

Ford knew what they were doing when they designed their filtration system. I wouldn't try to fix something that isn't broken.

Re: Oil Filter-ology
 

[attach]Attachment 480060[/attach]

Re: Oil Filter-ology
 

Yup, just like that one..^^^^^^.....Mark

Re: Oil Filter-ology
 

Just to be clear 51 Merc-CT; the 2 CDN 8BA's (51 M3 and 50 Meteor) do not have any restriction of any type (except the diameter of the tubing) from the block to the interior of the filter housing. They have one drain hole in the return pipe located in about the same place as shown in your picture. The diameter of the hole I am not sure of but a piece of stove-pipe wire is a snug fit. It seems the engineers that designed these old trucks had a different thinking process depending on which side of the 49th parallel they were on?

Re: Oil Filter-ology
 

They did a lot of things differently up north in Canada. A person would have to check the system starting at the block ports to see if there is a 1/16" restrictor orifice in the line somewhere. Ford of Canada made several different oil filtration and oil cooler systems over the years for trucks and military vehicles like the Universal Carrier. They modified the oil distribution manifold on the back of the block in several ways for the different systems they produced. Nothing surprises me when referring to products manufactured by Ford of Canada. The flow to the filter has to be reduced to maintain oil pressure in the engine. The restrictor orifice is the easiest way to control that.

Re: Oil Filter-ology
 

My oil filter canister inlet hole is missing a restrictor. Any suggestions on how to make one/ where to buy one??
THX!

Re: Oil Filter-ology
 

Ckrivin: Read the thread below , especially the posting by JSeery. Also read all the links in the posts. There are two styles of resterictor fittings. One for Ford and one for Merc. The Weatherhead fitting is easier to find.
https://www.fordbarn.com/forum/showthread.php?t=195393

Re: Oil Filter-ology
 

Solder a regular fitting closed and drill it out to .060 and you will be good to go.

Re: Oil Filter-ology
 

me again my only concern is oil flow in the flathead was never designed to accommodate a full flow filter ive seen some mods done but still wonder if they actually flow suffient oil and in fact causing a problem in the long run due to reduced oil flow inside the engine

Re: Oil Filter-ology
 

Re: Oil Filter-ology
 

yeh got to luv it 38c shorts singlet sweaty as and covered in grease oil and dirt [you cant grow roses without manure]

Re: Oil Filter-ology
 

You can put your concerns to rest. The oil conversion where the oil is pumped to a remote filter and then returned to the engine directly into the original internal passage will NOT cause any short or long term problems. I know from personal experience having converted many engine's for others as well as my high mileage daily driver. To date two round trip cross country journeys with absolutely no issues and that includes feeding the oil to a set of original ARDUN heads.

The Ford flathead internal oil cross passage measures .421 in diameter that's the largest internal passage. When I do the conversion I make sure all of the fittings I use match's the .421 internal dimension. The oil lines used are 1/2 internal diameter. The correct oil filter to use is the Ford Motorcraft FL-1A this filter will not restrict the flow its a perfect filter for this type of conversion.
Point is when you do the conversion simple back yard hot rod ingenuity is all it takes to get it right so the engine will survive.
Ronnieroadster

Re: Oil Filter-ology
 

I run a true 100% full-flow system on my 32 Cabriolet (284 cubic inch stroker engine). I have a modified oil pump -> The bottom plate of the pump has been modified to take the entire oil volume out of the pump, through a hard-line and bulkhead fitting in the side of the oil pan, through a full-flow filter and back to an enlarged oil galley on the side of the block. The oil-pump casting has been plugged where the oil normally exits the pump gear area and goes through the long-slot to the pressure galley (it was blocked off). Though this setup is a bit more complex that the '95%' setup that many use - it delivers 100% filtered oil to the engine.

I've always snickered at the claim of '95%' filtration for the guys that make mods to pull the oil from the original oil-galleys, then through a filter - the number seems a bit optimistic to me in that these systems pump unfiltered oil to the rear main bearing - so I consider these 95% systems to be about '66%' . . . but hey, we can calculate it a lot of ways. LOL

Re: Oil Filter-ology
 

Dale I have seen a serious problem develop with the oil pump conversion your running. That pertains to the oil line in the pan when it comes off or begins leaking. Complete disaster happens. Had a few fellows using the conversion sold by an un named source who experienced this type of failure.
Ronnieroadster

Re: Oil Filter-ology
 

I've had the system you are probably referring to on my engine for 25 years with no problems. I would suspect improper installation caused the problems you are referring to.

Re: Oil Filter-ology
 

Has anyone else had issues with full-flow filter systems trapping air? I've had two engine failures with what is usually called the 95% filter modification. Both lost #8 rod bearing in a few 1000 miles.