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I thinnk I just foud out that I have a WW2 oil filter instead of an M38 unit... see pics below... I had totally forgotten about this, since I am working on the electrics, and looking for some stuff, I found this.







Some chalk so you can see the lettering...




I have tried to take the cartridge out, but have not been able... is there a trick to this? I haven't forced anything, and the cartridge spins freely... I'm guessing I will have to remove something else, other that the top, but have no idea...




Also, anyone willing to trade it for the correct application? I mean, if a WW2 assembly might have been compatible, I can keep it, but if someone has a CUNO out there that is willing to trade, I would be more than happy to.

Thanks,

Jorge

Hello Jorge,

The first 6 M38 Pilot models used that filter. All the production M38's and the first 2000 or so M38A1's used the Cuno. The M38A1 went back to that filter and in the late 50's and early 60's the M38's that needed new filters would usually get that filter instead of a Cuno.

So yes the military junior you have could be a WWII, or later M38A1 or M37 unit. The choice is yours.

For the Cuno to perform it's filtering task it's "T" handle had to be rotated at least once each week. When it was ignored the sludge would build up quickly and clog it up. Then corrosion would attack the fine plates and voila it won't turn anymore at all.

Several manufacturers made those military juniors and the WWII guys that are very detail oriented actually nail down which brands were used on which WWII jeeps.

So I would be ok using it, like it would be a motor-pool change or something similar? How do I extract the filter unit? It spins, but I cannot pull it out... Can I pry the unit somehow, taking into account that I wouldn't wish to misalign/force and break anything inside?

How does the CUNO work? What's the principle behind the rotating filtering?

Thanks, as always, for your input, Wes! Sure wish I had a neighbor like you or some other guys in this group!

Jorge

I noticed your post on the G503. I also noticed Joel Gopan's reply about protecting the edge of the cannister with a piece of wood when you use a couple of crew drivers to leverage the element out.

If you do a search of this topic on the G503 board someone else a few months ago asked the same thing. I responded that they should be careful prying against the cannister. Joel had the gonads to say I was foolish in my advice and it wasn't necessary.

The Cuno filter is a stack of thin stainless steel discs very close together. They use a cleaning wire between each disc which when you rotate the main "T" handle shaft will scrape each side of each disc clean and dump the crud in the bottom of the bowl. Then every 6,000 miles you are to remove the core and clean the bowl. Cuno is still alive and still manufactures this style filter. It gets it's bad rap from the bad habits of it's owner/operators. It is actually a very good system and has been used on airctaft from the 1920's thru the end of WWII.\
http://www.cuno.com/library/LITHSAKDDS.pdf

Here is a list of filter manufacturers and the correct part numbers for the Fram junior filters.

AC - P203
Big A - 92010
Bosch - OX79
CarQuest - 85010
Fleetguard - LF-568
Fleetrite - LFR8574
Ford - 9N18649, 9N6714,
Fram C3, C3P
Hastings - LF130, LF102
Lee - 70FR
Motorcraft FL144
NAPA – 1080, "Gold" FIL1010, FIL1071
Purolator - L20700, L20110, PM352, P70AC, T110, L20701
Western Auto - 5815?
Wix – 51010

When draining the Fram Junior cannister during an oil change on a M38A1, how do you prevent making a big mess? Given the usual orientation of the drain plug (bolt) and the other engine components in the vicinity, I've found it difficult to contain the oil stream once the drain is out. What's the secret?
Thanks,
Warren

You can use a piec of funnel shaped metal or card board to direct the flow forward and outboard to a small plastic bucket or you can unbolt the filter housing from it's mount bracket and move it forward and outboard or you can not drain it but instead when you pull the element out use a turkey baster to suck the oil out and wipe the interior up with a rag and some solvent.

Thanks, Wes. With Thanksgiving done and the turkey baster now freed up, I'll try that approach next oil change.