M38 Distributor Rebuild

Discussion topics on Willys Overland M series vehicles
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Naugha
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Post by Naugha »

I'd recommend a slotted spring pin (a.k.a "roll pin") instead of a cut nail. My local Ace Hardware has an assortment in the Hillman bins. Ron
Excellent!

Any advice on the oil seal?
Did I press it wrong?
*Buy one from xxx.com?
*Pull it / fill with Permatex ?
*Forget about it and wait to see if it leaks?
*Chewing gum? 8)
Don Alvarez
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Post by RonD2 »

Don,
Not sure about the seal. In the September 1955 ORD9, Figure 06-7 on page 105, I see item AA, listed on page 146 as Seal, Oil type, 0.756 OD, 1/8 width, 0.500 shaft diameter (WO-119054, Ord 7351671). Is this the seal? If you can't find the real thing, perhaps those dimensions can help find a suitable substitute?

By the way about the roll pin, also looking in the September 1955 ORD9, Figure 06-7 on page 105, I see item HH, listed on page 144 as Pin, Straight, Headless, 1/8 x 7/8 (Ord 112011). The dimensions should help find the correct size pin.

Good luck!
Ron D.
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51

“The only good sports car that America ever made was the Jeep."
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Naugha
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Post by Naugha »

Somewhere in TM 9-1825B / Section 5/ Group 3/ P.240-248

It says to press the upper bushing (bearing) “flush with face of the bearing bore” ..... which maybe I do not exactly understand.

Should I have pushed that upper bushing/bearing flush with the top of the shaft hole (which I did) or should I have pushed the bushing a little further in so that the top was even with the bottom of the oil seal section of the ‘bore’.

.... and I assume the oil seal groove faces down when pressed into the top of the shaft bore.

..... and what exactly bad happens if a little lubricant leaks past that seal?

..... and why are the bushings easy to find but not the seal?

This too shall pass. 8O
Don Alvarez
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Post by RonD2 »

Don,
“flush with face of the bearing bore” seems pretty clear to me.

When you took it apart, did you mark, measure, or photo the position of the bushings? and other parts?

I don't know for sure, but would imagine that if lubricant leaks past the seal the parts intended to be lubricated won't have it? Might be compensated by more frequent lubrication of the oiler wick? I don't think I'd leave the seal out on purpose. Use the old one until a new one turns up? What's it made of?
Ron D.
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51

“The only good sports car that America ever made was the Jeep."
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Naugha
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Post by Naugha »

When you took it apart, did you mark, measure, or photo the position of the bushings? and other parts?
Yes. I have photos of each step but the oil seal and bushings are inside the bore .... oh, maybe if I had looked closer at the inside spacing.

Wes has mentioned before that the manuals were written for folks with shop training and experience..... like the ‘bore’ is the center of the ‘shaft hole’ and does not include the larger diameter top section where the seal sets ?? Right?

I think there is another part of the manual that tells you to draw a pic of the cam orientation without emphasis on ‘why’. In a past post Wes explains with pics the importance of properly clocking these parts..... I need to reread that post.

This all can be frustrating but most things made by humans can be fixed by humans. I will take a closer look at sites that use parts lists with few pictures and call around about the oil seal.

*** Rick’s parts may come in today. :)
Don Alvarez
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Naugha
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Post by Naugha »

September 1955 ORD9, Figure 06-7 on page 105, I see item AA, listed on page 146 as Seal, Oil type, 0.756 OD, 1/8 width, 0.500 shaft diameter (WO-119054, Ord 7351671). Is this the seal? Ron
Yes. That's the one. It looks similar to other oil seals but smaller. It is a hollow metal ring filled with a plastic/rubber insert. The plastic/rubber material has a center groove.

I think I smashed it against the upper bushing which was not "seated flush with the bore."

I am very good at smashing things with my HF press. If you need anything smashed I am your go-to guy.

Don
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Post by RICKG »

Mornin Guys. last time I checked the parts were in Jacksonville "in transit arriving late" USPS go figure..
Don, it is possible to install the cam plate 180 deg off so pay attention.
keep 'em rollin'
RICKG MC 51986 DOD 01-52, '50 CJ3a
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Naugha
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Post by Naugha »

Don, it is possible to install the cam plate 180 deg off so pay attention. RickG
Yes Sir. I will also use the Wes album pics as a guide.

Don
Don Alvarez
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Post by Naugha »

I think I found the needed distributor oil seal on one of the sites that use long lists for small items rather than pictures.

The numbers don’t match what we found in the parts manual but the owner says it is the same seal.... very inexpensive. I bought two in case I screw up again. There is wisdom in redundancy.... just ask RickG.

I found an overseas source for some of these hard to get 24V distributor parts and think the assembly can be built for far less than the going price..... for those who want a backup for their backup. :wink:

Soon we will reassemble Humpty Dumpty; a glorious endeavor filled with anticipation, the father of restless sleep, disaster’s child, a gathering place for all who live on the edge. 8)
Don Alvarez
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Post by RICKG »

according to tracking the parts have been in Jax since the 8th :x
you think they can't find Ocala? I know it from my motorhead days as the home of "Big Daddy"..
keep 'em rollin'
RICKG MC 51986 DOD 01-52, '50 CJ3a
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Post by 4x4M38 »

Don Garlits!!
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Post by RonD2 »

Swamp Rat.
He's what the crowd came to see.
Ron D.
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51

“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari

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Naugha
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Post by Naugha »

Meanwhile, back at the Barn, two other distributors were discovered in Don's stash and he seeks info on part transplant viability with his 24V / IAU4006AUT.

With enough parts the noob hopes to eventually assemble a backup or two.
Will some stuff from these distributors work on a IAU4006AUT?


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Don Alvarez
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Post by RonD2 »

Micrometer is your friend.
Ron D.
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51

“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari

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Post by wesk »

Or a parts list for the 4008 series so you can simply compare the list with your own M Jeep parts list.

Just go to my photo album and review the IAD 4008 data at: http://www.willysmjeeps.com/v2/modules. ... _album.php

Here's you IAU4006AUT List:
Large file: http://willysmjeeps.com/v2/modules/gall ... AUT_UT.jpg

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IAD4000 series parts list:

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Large file size photos of these four pages are in my photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
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. ... _album.php
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