Transfer case overflow problem

1941 - 1945, MB, GPW Technical questions and discussions, regarding anything related to the WWII jeep.
semberae
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Re: Transfer case overflow problem

Post by semberae » Mon Oct 28, 2019 10:30 am

Thanks Bruce and Ron. :) :)

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Re: Transfer case overflow problem

Post by Chuck Lutz » Tue Oct 29, 2019 11:44 am

For years before Mike Stopforth passed away, we noticed that for the FORD T/Cs, there was no number change, but the cases were different.
Willys managed to change the part number....so we never used the ones with the large opening because of this leaking problem.
GPW Transfer Case EARLY Lg Opening.jpg
GPW Transfer Case EARLY Lg Opening.jpg (74.92 KiB) Viewed 258 times
Transfer Case GPW-7705 Front LATE.jpg
Transfer Case GPW-7705 Front LATE.jpg (191.58 KiB) Viewed 258 times
Note that the later case has holes for the shift rails and not just a huge opening....

Al Brass' solution back in the day was to sandwich a very THIN piece of brass with two hole just large enough for the shift rails to pass through.

However, before going any further, you need to confirm you are not transferring gear oil from the T84 to the T/C...which only exacerbates the problem! Do that by opening both FILL plugs to see if the T/C has an excess run out and then check the T84 to see if it is low.
Then take another 30 minute drive with a good part at that 35MPH sweet spot and return home.
Recheck the levels....this will tell you if the rear T84 bearing is allowing oil to pass through and needs to be replaced with a SEALED-BOTH-SIDES bearing with sealant on the splines and bearing as explained by "MartySoCal" some time ago.

Now, if that is not the problem and the T84 is right up to the fill plug and the T/C is low, you have a leak, or as noted, you have the EARLY case and the high revs splash enough gear oil to escape the vent. Again, as Joel mentioned, there should be a felt disc under the cap. If the leak persists and you intend on driving at 35MPH plus, then you need to either use a gasket or a brass shim or just get a LATE GPW T/C case and build it up.
Chuck Lutz

GPW 17963 4/24/42 Chester, PA. USA 20113473 (USA est./Tom W.)
Bantam T3-C 1947

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Re: Transfer case overflow problem

Post by Joe Gopan » Tue Oct 29, 2019 4:14 pm

I am lucky enough to have been at this when original parts were plentiful My T-84 was assembled with a like new case and an A-1195 NOS crated Transfer. I check it a few times a year the same fill plug is usually down about 1/4" but there are no oil spots on the garage floor,the bottom of the transfer does have wet spots from wicking caused by saturated gaskets.Checking Oil Levels in JEEPs is a way of life It's been installed since 1971.
The thin brass baffle is an excellent Idea, too bad there is no easy way to check the case to see if it has the large opening. Perhaps the dealers will offer these baffles .
2011 MVPA PIONEER AWARD - MVPA #1064
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Bill H.
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Re: Transfer case overflow problem

Post by Bill H. » Tue Oct 29, 2019 4:17 pm

Chuck Lutz wrote:
Tue Oct 29, 2019 11:44 am
For years before Mike Stopforth passed away, we noticed that for the FORD T/Cs, there was no number change, but the cases were different.
Willys managed to change the part number....so we never used the ones with the large opening because of this leaking problem.

GPW Transfer Case EARLY Lg Opening.jpg

Transfer Case GPW-7705 Front LATE.jpg

Note that the later case has holes for the shift rails and not just a huge opening....

Al Brass' solution back in the day was to sandwich a very THIN piece of brass with two hole just large enough for the shift rails to pass through.

However, before going any further, you need to confirm you are not transferring gear oil from the T84 to the T/C...which only exacerbates the problem! Do that by opening both FILL plugs to see if the T/C has an excess run out and then check the T84 to see if it is low.
Then take another 30 minute drive with a good part at that 35MPH sweet spot and return home.
Recheck the levels....this will tell you if the rear T84 bearing is allowing oil to pass through and needs to be replaced with a SEALED-BOTH-SIDES bearing with sealant on the splines and bearing as explained by "MartySoCal" some time ago.

Now, if that is not the problem and the T84 is right up to the fill plug and the T/C is low, you have a leak, or as noted, you have the EARLY case and the high revs splash enough gear oil to escape the vent. Again, as Joel mentioned, there should be a felt disc under the cap. If the leak persists and you intend on driving at 35MPH plus, then you need to either use a gasket or a brass shim or just get a LATE GPW T/C case and build it up.
Chuck, he confirmed there was no transfer of fluid in his second post.

Great comparison pictures!
Bill H.

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semberae
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Re: Transfer case overflow problem

Post by semberae » Tue Oct 29, 2019 7:43 pm

The felt disc doesn’t help, I have tried that. I know I have the early TC.


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Re: Transfer case overflow problem

Post by Joe Gopan » Tue Oct 29, 2019 8:00 pm

I thought that the felt is a fix and the breather just has a baffle.
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

semberae
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Re: Transfer case overflow problem

Post by semberae » Tue Oct 29, 2019 8:11 pm

The vent actually has 2 baffles just below the holes in the vent tube. The felt will get saturated with gear oil and block the air flow of the vent and the the pressure is relieved thru the output shaft seals. Ask me how I know.

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Re: Transfer case overflow problem

Post by Chuck Lutz » Wed Oct 30, 2019 10:58 am

As long as you run the jeep at higher speeds for sustained drives (35-35MPH) the sloshing around of gear oil in the T/C will overflow the breather tube when the early case is used even if there is no transfer of gear oil from T84 to T/C.

Ford guys can't tell since the part number for Early/Late is the same. Willys guys have it easier....the cases have DIFFERENT casting numbers which enable you to tell which have the EARLY feature (large opening) or the LATER feature (shift rails openings only). Here ya go, Willys guys...

First, the EARLY part numbered case:
Early C-18-15-10.jpg
Early C-18-15-10.jpg (45.95 KiB) Viewed 212 times

Next, the LATER style with only the shift rail openings:
C-18-15-10-1 Code.jpg
C-18-15-10-1 Code.jpg (96.05 KiB) Viewed 212 times
Be advised that these cases continued to have changes to them through the CJ era so numbers continued to be changed! The larger shaft opening for the intermediate shaft is one example!
Chuck Lutz

GPW 17963 4/24/42 Chester, PA. USA 20113473 (USA est./Tom W.)
Bantam T3-C 1947

semberae
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Re: Transfer case overflow problem

Post by semberae » Wed Nov 06, 2019 5:20 pm

semberae wrote:
Tue Oct 29, 2019 7:43 pm
The felt disc doesn’t help, I have tried that. I know I have the early TC. .

Chuck Lutz
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Re: Transfer case overflow problem

Post by Chuck Lutz » Thu Nov 07, 2019 11:22 am

Either you address the case opening, or install some Rube Goldberg plumbing to deal with the overflow.
In other words....you can FIX the problem or just address the symptom....pick your poison.
Chuck Lutz

GPW 17963 4/24/42 Chester, PA. USA 20113473 (USA est./Tom W.)
Bantam T3-C 1947

semberae
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Re: Transfer case overflow problem

Post by semberae » Thu Nov 07, 2019 11:56 am

Right now I am just trying to address the symptom till when I do have to pull the Transfercase. No big deal.😎

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Re: Transfer case overflow problem

Post by Chuck Lutz » Thu Nov 07, 2019 12:27 pm

You could do what one of my friends did until he could address the problem in the off season....get some Pampers (diapers/nappys) and shove one up around the T/C vent. Then you can replace it when it gets oily and at the same time, top off the T/C gear oil. That will keep the leak from dripping out as you drive and making a mess of the underside of the jeep which can happen on a long enough drive.

DO NOT under any circumstances try using 140 wt. gear oil or anything like STP in lieu of the 90 wt. recommended.
Chuck Lutz

GPW 17963 4/24/42 Chester, PA. USA 20113473 (USA est./Tom W.)
Bantam T3-C 1947

semberae
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Re: Transfer case overflow problem

Post by semberae » Thu Nov 07, 2019 1:21 pm

No pampers for my Jeep. I was told when I first got my GPW and started working on restoring it, that Jeeps like to mark their territory( leaking seals, oil weeping thru paper gaskets, and just general leaking. I’ve got used to cleaning up the the oil that comes out the vent. It lets me check out other things under neath that you normally wouldn’t check if everything was working 100%. Like I said before no big deal.😎👍 I am using 90wt GL 1 in the TC and trans.👌

semberae
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Re: Transfer case overflow problem

Post by semberae » Fri Nov 08, 2019 6:50 am

semberae wrote:
Thu Nov 07, 2019 1:21 pm
No pampers for my Jeep. I was told when I first got my GPW and started working on restoring it, that Jeeps like to mark their territory( leaking seals, oil weeping thru paper gaskets, and just general leaking. I’ve got used to cleaning up the the oil that comes out the vent. It lets me check out other things under neath that you normally wouldn’t check if everything was working 100%. Like I said before no big deal.😎👍 I am using 90wt GL 1 in the TC and trans.👌.

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