Oil filter question

[Herrmann_Sherman]

In the next days I will change the oil of my M38/CJ-3A mixture. I also will change the oil filter.

My question is as follows:
Is the M38 oil filter the same as on the CJ-3A or are they different?

Thank you for an answer

Herrmann_Sherman

[wesk]

From the Willys factory the M38 used a CUNO style oil filter and the CJ3A used a Fram cannister oil filter. The military eventually swapped most of the Cuno's for the old Military Junior cannister filters made by Fram, Puralator & AC. These were used on the WWII MB/GPW and the M38A1's from mid 1953 and on. The civilian Fram is a different creature and uses a different element.


M38 with original correct Cuno oil filter.


M38A1 with Cuno oil filter.


M38A1 engine with Military Junior oil filter.



Here's the assortment of civvy oil filters used on the CJ2A & 3A.


Here's a civvy Fram on an early CJ3B.


The Military Junior filter is on the left and the CJ civvy filter on the right.
_________________
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules.php?set_albumName=Wes-Knettle&op=modload&name=gallery&file=index&include=view_album.php

[Herrmann_Sherman]

So I hope that I can tell my dealer that I have an Military M38 filter?
The top is stamped

"MILITARY STANDARD FILTER"
"COVER ASSEMBLY 25791"
"PUROLATOR PRODUCTS INC."

[Oldsalt]

If you have the military size filter it is a Fram C-4 or equivalent. The local parts places won't usually have a listing for a military jeep. If it is the civilian size they will have a listing for a CJ3A.

[wesk]

Several manufacturers produced the military junior for the military. Most common are:
Fram used C-21
Puralator used PD-51
AC used C-26

There are a couple dozen replacement numbers that will work. Caution with the gasket size. Some of the elements that will fit have a wrong size gasket with them.

Here's a good thread on these:
http://g503.com/forums///viewtopic.php?t=9376&highlight=

The best list in that thread is:

[Herrmann_Sherman]

ok, guys. I´ll try it out.
Many thanks!!

Herrmann_Sherman


Dealer was sending me:
Standard Military Junior Filter
ACP-115

[Herrmann_Sherman]

But I don´t understand how the circulation of the filter is working. I´ve found the inflow-line but how is the oil leaving the case???
I just can find the hose but no hole to suck the oil....
It seems that the oil pressure changed from 4 to 3,6...
and I´ve taken out some snippets of old gaskets in the housing....

Oil is Castrol Classic XL SAE 20W/50...

[wesk]

in thru the outer circumference of the filter element and out thru the center and then thru the center filter tube and down to the timing gear cover on the engine.
_________________
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules.php?set_albumName=Wes-Knettle&op=modload&name=gallery&file=index&include=view_album.php

[skyjeep50]

Oil flows up to the filter from the oil gallery along the left side of the engine, outlet is just under the fuel pump, and then leaves the filter and goes down to the timing gear cover. There it lubes the timing gear and flows back to the oil pan.
Pic 1 is of my M38 motor with the Cuno oil filter - return line can be seen routed to the timing gear cover. Pic 2 is M38A1's motor (with shiny new motor mounts installed - had to pull the motor to get them on), the return line can just be seen routed from base of the filter housing to the timing cover.


_________________
1951 M38