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M38A1 Oil Filter
Posted: Sat Oct 06, 2012 2:52 pm
by Deadguy
I wanted to replace the oil filter element, and when I compared my oil filter to the ones I see online, there is a huge difference. My oil filter container is only like 3 inches high, and all the others I see are much larger. Can anyone tell me what is going on with this?

Posted: Sat Oct 06, 2012 3:21 pm
by frankthecrank58
hey Deadguy! what you have is the Cuno style oil filter which has a cartridge that you clean rather than replace. if you have the tm 9-8012 manual,( on this site in the downloads, i believe) it tells you on page120 and 121 how to remove , clean, and re-install this type of filter. the other pic you show is the canister with a removable filter.
Posted: Sat Oct 06, 2012 3:24 pm
by wilfreeman
Didnt they stop using the Cuno type in real early production 'a1s?
Posted: Sat Oct 06, 2012 3:29 pm
by frankthecrank58
i don't know, but the filter in deadguy's pic is the same as the one in my m-38 manual so that's why i suggested he look online at how to clean his. my m-38 has the disposable canister and it's d.o.d. is 9-9-52.
Posted: Sat Oct 06, 2012 3:36 pm
by wilfreeman
I think they used the Cuno in very early production 'a1s, then switched over to the Military Junior type.
Posted: Sat Oct 06, 2012 3:36 pm
by circleburner12
deadguy, ive got a oil filter set-up for sale, if interested.
Posted: Sat Oct 06, 2012 4:09 pm
by Deadguy
well, I don't want to replace it if I don't have to. I have a very early M38A1, with the swing up grill and everything.
Posted: Sat Oct 06, 2012 4:14 pm
by wilfreeman
The Cuno type should be correct for an early 'a1 I think.
Posted: Sat Oct 06, 2012 4:39 pm
by Kendall
Don't forget, to properly use the Cuno style oil filter, that handle on the top needs to be turned daily.
Kendall
Posted: Sat Oct 06, 2012 4:52 pm
by Deadguy
oh yeah? Clockwise? Counterclockwise? How much do I turn it?
Posted: Sat Oct 06, 2012 7:56 pm
by frankthecrank58
according to my owners manual; daily, rotate handle several times( doesn't say which direction so probably doesn't matter) weekly; remove drain plug from bottom of base to allow accumulated foreign matter to drain. every 1,000 mi; disconnect lines, remove filter from bracket, remove six nuts, lockwashers and bolts securing filter unit to base and remove unit. clean discs well in a dry-cleaning solvent and oil mix. reassemble and reinstall. whew.....sounds like a lot of work! my manual # is CDN-OM9-804 and this info is on pg 48 para 76. don't know if this helps you but at least i got to practise my typing! cheers. frank.
Posted: Sun Oct 07, 2012 6:49 am
by Xamon
Sorry to highjack here but.... You have the canadian manual!? Any chance we can get you to share/scan it? Please? It would be nice to have the 100% correct manual and info.
Posted: Sun Oct 07, 2012 7:16 am
by wilfreeman
I think I've seen one online. It is a canadian site - he has m37 manuals too. I'll look when I get a chance.
Posted: Sun Oct 07, 2012 7:51 am
by wesk
Again we are forgetting the easiest source for data. The M38A1 operator's manual addresses the Cuno filter (TM 9-804A for early A1's) and how to service it. The M38A1 ORD 9 shows clearly at which serial number the M38A1 switched to the old large military junior filter.
The later M38A1 operator's manual on page 1 at the bottom alerts you to the fact there was an ealier M38A1 operator's manual TM 9-804A dated Jul 1952 and that the TM 9-8014 supercedes it. The TM 9-8014 also states on 60 and 62 (Lube chart) how to service the Cuno while it illustrates the later military junior and describes only the later military junior in the engine repair chapter.
If you own an early A1 (52/53 model) then you should get a copy of the TM 9-804A. If you can't locate one then download the M38's TM 9-8012 PDF form free off our downloads page and print the Cuno service directions and add them to your TM 9-8014.
Finally I have enough detailed photos in my photo album to answer 80% of the questions that come up here. For Cuno's one only need to look here:
http://www.willysmjeeps.com/v2/modules. ... _album.php
Posted: Sun Oct 07, 2012 8:10 am
by frankthecrank58
i got my manuals from Brian Asbury, from Milton Ont. He is a member of this forum. he also sent me my new data plates. he has a large inventory of NOS parts available. if you want a hard copy of the manual go to the members list and send him a PM. the only manual i have that says CDN is the operators manual. the others i have are the same as the downloads on this site. when i become more computer literate, and have access to a scanner, i will share the manual. the manual cost me $24.00 plus the Gov't Sanctioned Theft (GST) hope that was helpful! cheers, frank