u joints don’t fit.

[Naugha]

Today I attempted to install new (no-name/cheap) u joints on my M38 project. I watched all the videos, looked at several diagrams and dusted off my HF shop press. The yokes and retaining ring grooves were cleaned and given a spot of grease. When problems arose I Google searched the site but was unable to find a thread on my problem.

* The u-joints smoothly pressed in flush with each side of the yoke. The cap on one side was then pressed further in and the retaining ring was set into its groove. Fine. Just like in the videos.

* But..... there was not enough travel length left for the second cap to be pressed below its retaining ring groove.

* I checked my alignment and pushed the HF shop press to max thinking it just needed more persuasion. After cracking two u joints on two different yokes I tossed everything in the can..... no pics. #&$@%#@$&

Is going cheap with the unbranded u joints probably the source of my problem? The ad said “fits M38” and I have often used the supplier.

What u joint brand/source is known fit the M38?
Or is user error lurking somewhere in my method?
_________________
Don Alvarez
Retired HS Teacher
Central Florida
M38 Project

[RonD2]

Which propeller shaft Don? Front or rear? Are you sure you have M38 shafts? Photos of the shafts and yokes would help. Anything like what's in the Reference Guide or the ORD9?

Starting here: http://willysmjeeps.com/v2/modules.php?name=Forums&file=viewtopic&t=11544&highlight=drive+shaft+joint

And here: http://willysmjeeps.com/v2/modules.php?name=Forums&file=viewtopic&t=9100&highlight=spicer+joint

Standing by to see if you're sure you have M38 propeller shafts....
_________________
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

[Naugha]

Here are the props. The new u joints did not fit either one.
The props and old u joints are marked Spicer.

I will make measurements of the yokes and replacement u joints on my next trip to the Barn. Thanks, Don







_________________
Don Alvarez
Retired HS Teacher
Central Florida
M38 Project

[4x4M38]

Don,
Is there any chance a roller came out during assembly?

That would keep the whole thing from compressing properly.

Don’t ask me how I know.
_________________
Brian
1950 M38
MC11481
http://www.willysmjeeps.com/v2/modules.php?set_albumName=album372&op=modload&name=gallery&file=index&include=view_album.php

[wesk]

Don,

Start in my photo album in the sub-album M38 running gear. You first accurately measure all parts of the shaft assemblies you have and compare them to the Willys blueprints in my photo album.


Rear Shaft PN 801675
Large file: http://willysmjeeps.com/v2/modules/gallery/albums/album167/MC_Rear_Shaft_801675_sm_b.jpg


Rear shaft 807690 (925896)
Large File: http://willysmjeeps.com/v2/modules/gallery/albums/album167/807690_925896_Rear_Drive_Shafts_smb.jpg

I am still looking for front shaft blueprints.
_________________
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

[Naugha]

[RonD2]

Don,
I'm guessing that your cheapo unbranded u-joints didn't come in a box that was marked with a part number either? It stinks when vendors sell new parts without any sort of packaging to identify the maker and part number, and even if you ask, they can't, or worse, won't tell you. Sometimes I can understand this for parts that are unique to the M38, but not for common parts like U-joints that are otherwise available most anywhere.

Along with the blueprints, the M38 Reference Guide has 3-4 pages of pretty good prop shaft descriptions, including some dimensions and identifying features.

My M38 came to me with good U-joints so I can't confirm from personal experience what the correct part number for the M38 actually is, but some research seems to point to the Spicer 5-153X and 5-1310-1X, both commonly available on-line or at local auto parts stores, prices from $13 to $22 each. If you google "Spicer 5-153X" you'll get hits that give the dimensions for these U-joints that you should be able to compare with your old joints.

See the dimensions here: https://www.danaaftermarket.com/spicer-automotive/automotive-driveshaft/universal-joints/part/universal-joint/5-153X?partType=PART&catalog=PIMS_NA

There's lot of good info literature on that site, lube recommendations, torque specs, replacement u-bolt kits, etc.
_________________
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

[Naugha]

The Spicer 5-135x u joint spec (cap to cap) length is 3.219".
My unbranded joints by direct measure are 3.22" +/- .005' ... the same.

The distance between the inner lock ring groove edges of my yokes by direct measure is 3.15" +/- .01".

3.22" > 3.15" .... close but no cigar.

Neither my unbranded joint nor the Spicer 5-135x will fit.

3.22" - 3.15" = .07" too long .... which agrees with what I see in that when I press one end of the u joint just below the locking ring groove on one side of my yokes ..... the other end of the u joint is flush with the surface of the other side of the yoke.

I see the Spicer u joint and yoke retaining groove (dotted line) in the second blueprint but do not see measurements indicating the ‘fit’ values I found by direct measurement.

I am taking the props to my mechanic guy this morning. He will probably get a good laugh then explain where I went wrong.

This is why people drink.
_________________
Don Alvarez
Retired HS Teacher
Central Florida
M38 Project

[4x4M38]

.07” Don, not .17

Still, just over 1/16” interference.

It’s mind boggling to me Willys and it’s successors would design and supply prop yokes for these vehicles that would not all have the same length dimensions if everything else is the same.

Why?

I can see if other dimensions are different. If the whole yoke is different.
But just this one dim?
_________________
Brian
1950 M38
MC11481
http://www.willysmjeeps.com/v2/modules.php?set_albumName=album372&op=modload&name=gallery&file=index&include=view_album.php

[RonD2]

Brian,
Might be premature to say the yoke is out of spec?.....still trying to determine if it is in fact original Willys M38 shaft and yokes or not. The blueprints should have the dims but they're kinda hard to read....still examining them.

Don's photo's are hard to see as well --- do they look like yokes might have been replaced? Has he finished measuring the rest of the dims?
_________________
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

[wesk]

When a very technical topic like this pops up I often see folks just poke at it here and there without actually making a detailed examination of the facts and dimensions and without sharing all their dimension checks, just a little piece of info here and there. Often folks also communicate directly by phone or email on the topic and those pieces of info never find their way here to the original post.

[RonD2]

Thanks Wes. Blowing it up is a lot easier on the eyes. We've been waiting for you to wade in here and straighten us out.

I still can't find the dim between the snap ring grooves, but I might be blind.

Interesting note on the early drawing --- that the bearing races get tack welded in position.

I'm thankful that those drawings are available in this forum. Great stuff found nowhere else!
_________________
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

[Naugha]

[RonD2]

Still missing a piece of the puzzle? Determining the design spec dimension of what the distance between retaining clip grooves is supposed to be --- to see if yours is within spec?

If you did crush bearing roller pins (twice!) in your previous attempts, did you find those pins bent up or crushed in the bottom of the cup when you examined the debris after it broke? One pin mangled like no others? I sure would think that if a pin came out of place you'd also have seen or sensed that the cup wasn't properly seated and/or wouldn't spin like it's supposed to before pressing it?

Recommend that you consider removing the zerk fitting (if equipped) before pressing to relieve any possibility of hydraulic pressure from grease already in the cups.
Remove the cups before pressing to inspect and make sure everything is in order before pressing. Maybe off-shore QA isn't what it should be?

[danrothe2001]

1. Your measurements of the snap ring grooves are wrong. Inside to inside is irrelevant. Measure outside to outside and add the snap ring thickness to the u-joint width to find the dimension. This is the one that counts. Also note that some of the offshore u-joints use thicker snap rings which means that the u-joint will be narrower. Do not mix snap rings and u-joints.

2. Improper pressing will crush the ears and narrow the gap. The shop manual will show the proper way to support the u-joint to prevent this. Measure the dimension next to the driveshaft and the at the end. If it crushed they will not be parallel and you will get a smaller dimension outboard than inboard. The correct repair at this point is part replacement. The Bubba method is to find a piece of round stock slightly wider than the distance between the ears and drive it in to spread the ears until they are parallel again.

This info comes from 30 years of driveshaft repair and seeing most of Bubba’s screwups.

Dan