more transmission pics

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It never ceases to amaze me how many variations there are in the little Jeep Transmission..on the internals..
Each one I have taken apart..seemed to be a tiny bit different from others in the past.
Some had cork seals..some had rubber...some had what I guess is neoprene..??
The bearings vary also..in the number or "balls". (no comment)...some had sealed sides -only one- not both.. These are the bearings on the input shaft..
Roller bearings..that go into the back of the input shaft..they came in different diameters also.. I have miked NEW rollers -- right out of GI packages with different part numbers - There was a difference of from 1 to 4 thousandths on some.. I guess these were for differences in the output shafts.??? All in all -- this little T-84 will run forever - as long as there is someone who cares enough to take care of them.....
Gene -- top

[Robert Tofson]

I have read all the posts here about the "late" washer and seal. I still don't know if the group has come to agreement on (1) which way the seal goes in relation to the open or closed side. Closed flat side toward the T/C, meaning then that the seals open face would be looking toward special washer. (2) is an oil slinger still used? Al said..... "in Johns enlarged photo, the seal has the lip facing to the TC so they were intending to stop oil transferring from the TC to the gearbox".

Any help would be appreciated. Thanks in advance.

Bob

[Kilroy]

Robert, clarifying I am no T84 expert, by reading these posts and consulting manuals etc., my understanding of the different arrangements of the rear main drive gear bearing / oil sealing set up is the following.
Parts are listed front to back, starting from the snap ring installed on the shaft).

I put in bold in Arrangement c) what might answer your questions.


Arrangement a) (see for instance TM 10-1513, change 1, October 1942)

1) spacer (WO # A-738)
2) oil retaining washer (WO # A-410), a.k.a. "oil slinger"
3) main shaft bearing (WO # A-916), shielded side to the front

Arrangement b) (see for instance SNL G-503 January 1944, or figure 70 in TM 9-803 February 1944)

1) spacer (WO # A-738)
2) oil retaining washer (WO # A-410)
3) main shaft bearing (WO # A-916), shielded side to the back
4) oil retaining washer (WO # A-410)

Arrangement c) (as per Army Motor, December 1944, via Bob N’s site)

1) oil seal (WO # A-15428) w/ lip toward the front
2) spacer (WO # A-15427) w/ recessed end toward the front
3) main shaft bearing (WO # A-916), shielded side to the front
4) oil retaining washer (WO # A-410) w/ flat (closed) side to the front

This in itself seems clear, and it would seem three arrangements were used over time. However I am in doubt about some points.

The new parts (WO A-15428 and WO A-15427), according to the Army Motor article, were introduced on the assembly lines at the factories in November 1944 (judging from the referenced S/Ns). But,
Question 1: was the arrangement listed in the article, which refers to overhauling old transmissions in the field, also used at the factory?

Likewise, the Army Motors article refers to a previous TB 1803-1 (8 December 1943), which explained another procedure (presumably using old style parts) for stopping oil migration from TC to tranny. This procedure might be the same described, in April 1944, in Ch 2, Sect. II, para 9 a of TM 9-1803B, which in fact is one and the same as Arrangement b) above, thus also corresponding to an intermediate factory arrangement. But TM 9-1803B here is somewhat misleading because it mentions an “oil baffle” and states that “the oil baffle was not supplied on vehicles of early manufacture”. Now, if the new oil seal A-15428 was introduced in November 1944, this elusive “oil baffle” should actually be the standard oil retaining washer A-410, since no other part is listed in the SNL G-503 of that period, as far as I know. If that is so, I don’t know when MBs were ever produced without it, since TM-10-1186, which covers both MAs and early MBs, already lists the washer A-410. So,
Question 2: could it be that a third type of oil slinger/baffle/ washer/seal existed, and therefore a fourth type of arrangement, either factory or field, or is this just another instance of TM9-1803B being inaccurate?

[Bob N]

Interesting discussion. The "early" procedure may have been the turning around of the bearing on the main shaft. However, I haven't traced down any documents to support this. I do remember reading it somewhere, just not sure where.

[Robert Tofson]

Robert, clarifying I am no T84 expert, by reading these posts and consulting manuals etc., my understanding of the different arrangements of the rear main drive gear bearing / oil sealing set up is the following.
Parts are listed front to back, starting from the snap ring installed on the shaft).

I put in bold in Arrangement c) what might answer your questions.


Arrangement a) (see for instance TM 10-1513, change 1, October 1942)

1) spacer (WO # A-738)
2) oil retaining washer (WO # A-410), a.k.a. "oil slinger"
3) main shaft bearing (WO # A-916), shielded side to the front

Arrangement b) (see for instance SNL G-503 January 1944, or figure 70 in TM 9-803 February 1944)

1) spacer (WO # A-738)
2) oil retaining washer (WO # A-410)
3) main shaft bearing (WO # A-916), shielded side to the back
4) oil retaining washer (WO # A-410)

Arrangement c) (as per Army Motor, December 1944, via Bob N’s site)

1) oil seal (WO # A-15428) w/ lip toward the front
2) spacer (WO # A-15427) w/ recessed end toward the front
3) main shaft bearing (WO # A-916), shielded side to the front
4) oil retaining washer (WO # A-410) w/ flat (closed) side to the front

This in itself seems clear, and it would seem three arrangements were used over time. However I am in doubt about some points.

The new parts (WO A-15428 and WO A-15427), according to the Army Motor article, were introduced on the assembly lines at the factories in November 1944 (judging from the referenced S/Ns). But,
Question 1: was the arrangement listed in the article, which refers to overhauling old transmissions in the field, also used at the factory?

Likewise, the Army Motors article refers to a previous TB 1803-1 (8 December 1943), which explained another procedure (presumably using old style parts) for stopping oil migration from TC to tranny. This procedure might be the same described, in April 1944, in Ch 2, Sect. II, para 9 a of TM 9-1803B, which in fact is one and the same as Arrangement b) above, thus also corresponding to an intermediate factory arrangement. But TM 9-1803B here is somewhat misleading because it mentions an “oil baffle” and states that “the oil baffle was not supplied on vehicles of early manufacture”. Now, if the new oil seal A-15428 was introduced in November 1944, this elusive “oil baffle” should actually be the standard oil retaining washer A-410, since no other part is listed in the SNL G-503 of that period, as far as I know. If that is so, I don’t know when MBs were ever produced without it, since TM-10-1186, which covers both MAs and early MBs, already lists the washer A-410. So,
Question 2: could it be that a third type of oil slinger/baffle/ washer/seal existed, and therefore a fourth type of arrangement, either factory or field, or is this just another instance of TM9-1803B being inaccurate?

Thanks Kilroy for taking the time to help wade through this......you too Bob.

I have taken another look at TM 9-803 and am again unsure if the manual is correct, or for that matter what is and what is not. On page 126 there is an exploded view of the T-84. It does not show part number WO-A-15428 however below that is a list of parts and WO-A-15428 (oil seal) is listed with a note: Only to be used with transmissions with a raised "H" on the case, same with WO-A-15427 (spacer). My tranny has the "H".

Then,,,,,,,,,the exploded view in TM-9-803 does not agree with the sectional view in that the exploded view does not show an oil slinger on the T/C side of the bearing as does the sectional view. In talking with George Baxter at AJP's, he said the oil "new" seal replaces the oil slinger so that the sequence from the snap ring back toward the T/C is the special washer (spacer) with the lip goes over the snap ring, then the seal is placed on the shaft with the flat side toward the T/C,....then the bearing. The spacer with the lip goes inside of the seal so that the two are mated so to speak. He did not quote any manuals, just his experience in rebuilding trannies.

John Barton and I exchanged a couple of e-mails and he is looking into it as well. Interesting stuff, these old vehicles. Maybe part of the problem is fitting new stuff to old stuff

Thanks for the look guys,
Bob

[john barton]

I addressed this a little in one of the transmission posts...
then I bumped up the one with the pictures of the three arrangements..
it was from some posts earlier and was not really part of my 4 part long series...
I think I posted somewhere that this is a little confusing throughout the manuals and parts books...I don't know if I even really got all the dates
straight..
Kilroy's list of parts that went with each version is correct I think...
but there never was a picture of the final "seal" version..
click on the link in Bob's post that has the WWII army motors article..
even that picture is the old two oil slinger version...the text describes the seal version and how it is installed..
it does answer that the one oil slinger is still used...in the T/C..

the TM 9-1803B page 23 para 9 a discusses..the early version without a baffle,,
and how to turn bearing around, and add another baffle (oil slinger)
even the names are different throughout..!

post war parts books list the seal version parts, but still have early drawings...some with one slinger, some with two..

it is just one of many places where the books and manuals where not always up to date, or correct...

it took me a long time to figure out the piston T-Slot and oil squirt
hole on rods because of manual screw up's...just have to keep diggin.

John

[Robert Tofson]

John my tranny was missing the early spacer that is shown between the snap ring and the oil slinger.....and there was an oil slinger on the T/C side of the bearing. I was thinking the oil was migrating into the T/C from the tranny; seems that the two oil levels are different but I have read and been told the two cases will find their own levels Maybe the "new" and improved seal, that goes on the tranny side of the bearing only replaces one oil slinger but one should still be used on the T/C side of the bearing as mentioned in the Army Motors article that Bob provided?

Bob

[Bob N]

John my tranny was missing the early spacer that is shown between the snap ring and the oil slinger.....and there was an oil slinger on the T/C side of the bearing. I was thinking the oil was migrating into the T/C from the tranny; seems that the two oil levels are different but I have read and been told the two cases will find their own levels Maybe the "new" and improved seal, that goes on the tranny side of the bearing only replaces one oil slinger but one should still be used on the T/C side of the bearing as mentioned in the Army Motors article that Bob provided?

Bob

Yes, you would use the slinger on the TC side.

[Ron Fitzpatrick]

I have all of these different varients of spacers, seals, shims, slingers in stock if anyone needs them...

Give me a ring

Cheers,
Ron

I put in bold in Arrangement c) what might answer your questions.


Arrangement a) (see for instance TM 10-1513, change 1, October 1942)

1) spacer (WO # A-738)
2) oil retaining washer (WO # A-410), a.k.a. "oil slinger"
3) main shaft bearing (WO # A-916), shielded side to the front

Arrangement b) (see for instance SNL G-503 January 1944, or figure 70 in TM 9-803 February 1944)

1) spacer (WO # A-738)
2) oil retaining washer (WO # A-410)
3) main shaft bearing (WO # A-916), shielded side to the back
4) oil retaining washer (WO # A-410)

Arrangement c) (as per Army Motor, December 1944, via Bob N’s site)

1) oil seal (WO # A-15428) w/ lip toward the front
2) spacer (WO # A-15427) w/ recessed end toward the front
3) main shaft bearing (WO # A-916), shielded side to the front
4) oil retaining washer (WO # A-410) w/ flat (closed) side to the front