M38 52' oil canister maintanence?

joebuck · Post by **joebuck** » Mon Oct 20, 2014 6:47 pm

I have owned my restored 52' m38 for a year. Can someone lead me to a previous thread on how or what to do with the canister? I guess that is the oil filter? Thanks

Jim · Post by **Jim** » Mon Oct 20, 2014 7:10 pm

First, get the M38 Manual, available free herein for
downloading. Second, get lots of paper towels and
rubber gloves. Third, get an oil change receptical.
Fourth, follow the manual's directions. That should
do it.
PS: Quick Lube places probably don't have a clue.

Jim in Darkest Arkansas

Post by **wesk** » Mon Oct 20, 2014 9:33 pm

Which oil filter do you have? Cuno or Military Junior?

Cuno

Military Junior

joebuck · Post by **joebuck** » Tue Oct 21, 2014 8:39 am

Post by **wesk** » Tue Oct 21, 2014 9:19 am

Download the TM 9-8012 and review pages 118 thru 120. Download the ORD 9 SNL G-740 and review pages 21, 43, 44 & 45. These are both free downloads on our downloads page:

http://www.willysmjeeps.com/v2/modules. ... tit&lid=90

http://www.willysmjeeps.com/v2/modules. ... tit&lid=95

I have some excellent drawings in my technical photo album:
http://www.willysmjeeps.com/v2/modules. ... _album.php

Do feel free to use the several hundred technical photos in my albums anytime.
http://www.willysmjeeps.com/v2/modules. ... _album.php

Two cautions:
1-Exercise care aligning the gasket and bowl retainer.
2-You should rotate the "T" handle one turn each time you use the jeep if it's not a daily driver and once a week if it is a daily driver. Open and clean it's bowl each oil change for a lightly used jeep and every other oil change for a daily driver.

joebuck · Post by **joebuck** » Tue Oct 21, 2014 9:31 am

awesome! thanks so much. will follow to a tee

Now that i am looking, i think mine is a fram?

joebuck · Post by **joebuck** » Tue Oct 21, 2014 9:53 am

So i identified the oil filter wrong... i thought the pan was the oil filter. So i need to clean the oil pan and address the oil filter

joebuck · Post by **joebuck** » Tue Oct 21, 2014 10:58 am

Just took oil filter top off and my element is dry as a bone. it appears it is not working and has been rerouted? i guess the pan cannister is oil filter.. i am trying to find the owner who i bought it from and call him

Post by **wesk** » Tue Oct 21, 2014 11:12 am

What "pan cannister". The oil pan is only an oil pan. Nothing else. Post a photo of your "Pan Cannister".

Check the two hoses from the oil filter to the block and make sure they are not plugged up. One attaches to the front engine timing cover and the other to a fitting hiding behind the fuel pump. Disconnect the hoses and blow through them.

joebuck · Post by **joebuck** » Tue Oct 21, 2014 1:50 pm

Ok heres the deal or situation. i finally figured out difference from Oil bath Air Filter and the Oil Filter. Ha!

Called the guy that restored it 30 years ago and he bypassed the OIL FILTER!!!!....he said all the stock filter system does is or does starve the 1st plug/cylinder. He told me with light use just change the oil every year with 30 weight.

M606BR · Post by **M606BR** » Tue Oct 21, 2014 3:53 pm

Just to complement information regarding Cuno-type filter maintenance procedure:

According to the supplement to the TM 9-8012 from January 1958, there is a change to be done to page 63, table II, lines 6 and 7, as follows:

"On Cuno-type filter, turn the handle four to five complete turns." (after operation)

Post by **wesk** » Tue Oct 21, 2014 7:40 pm

Your budy was wrong. Put the oil filter back on the engine. The issue with low pressure to #1 rod bearing was not the oil filter. It was too large a spray jet for the timing gears. It was corrected by reducing the nozlle diameter from 0.070 to 0.040.

joebuck · Post by **joebuck** » Tue Oct 21, 2014 7:56 pm

Wesk , he was instructed to do this by willys overland factory. He restored this jeep in their plant on weekends using their tools and manuals and it seems personnel since his buddy worked in there.

So I guess I need to find out what nozzles diameter I have? If I have the big nozzle then I need to reduce them per you

Post by **wesk** » Tue Oct 21, 2014 8:23 pm

Interesting old tale. Having worked in a factory or two I can say I can't imagine Willys factory security allowing a civilian to bring a used M38 into their facility for repairs. I can imagine an employee carrying parts off the property to help his buddy repair his jeep though. When was this unusual trip to the Willys factory made?

Here's the location of the spray nozzle:

45auto · Post by **45auto** » Tue Oct 21, 2014 9:41 pm

There is some truth to closing off the oil filter, but still miss directed. This is where I need to find the documentation and I'm sure I have it some where or I wouldn't have known to look.

As Wes said, the system is a bypass type system and oil is bleed off the #1 main. To keep this from being a problem a restriction is needed in the system as a 3/16 hose coming off the #1 main would bleed off way too much pressure and could and most likely at some point starve the main for oil. In the canister type filter the filter acts as the restriction and knowing such, you should always keep a filter in the canister. The Cuno filter has a very small hole inside the outlet line connection which creates the restriction.

You can see where advice such as "always use a filter or plug it off" along with "its not that great a system" can turn into "just take it off and plug it!!" The system does work and I can't say either the canister or Cuno is better, I just use what came as original on my M38 and M38A1 and keep the oil changed. Also as Wes pointed out, there was a change in the Cam gear orifice hole from .070 to .040. If that small of a hole makes a big difference, you can see where an unrestricted 3/16 line could make even a bigger difference. The key here is to remember it is a System and it should be kept in tact for everything to work as it should.