Pin u-joint

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Haroldc30
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Joined: Sun Jan 06, 2019 12:52 pm
First Name: Harold
Last Name: Chambers
* REQUIRED* Type and Year of Model Ts owned: 1925 fordor. 1923 touring
Location: Winfield tn.
MTFCA Number: 50278

Pin u-joint

Post by Haroldc30 » Thu Feb 27, 2020 5:04 pm

Hello everybody. When using adjustable pinion bearing is it necessary to pin the u-joint.Thanks in advance Harold


Scott_Conger
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First Name: Scott
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* REQUIRED* Type and Year of Model Ts owned: '13, '15, '19, '23
Location: Clark, WY
Board Member Since: 2005

Re: Pin u-joint

Post by Scott_Conger » Thu Feb 27, 2020 5:08 pm

It really should be secured. Some have run without securing, but that is frankly bad practice. It will not be necessary to be fussy about the fit to the length of the front bushing, since your modern pinion bearing assembly takes care of end play. It's simply the proper way to complete the job.
Scott Conger

Tyranny under the guise of law is still Tyranny

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Henry K. Lee
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Location: South Pittsburg, TN
MTFCA Number: 479
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Re: Pin u-joint

Post by Henry K. Lee » Thu Feb 27, 2020 5:44 pm

Set it good! Make sure that the clearances are tight just like an original. If that retainer comes loose and that u joint is not tight to the bushing.., start looking for a new ring and pinion.

I personally add another stop collar in front of the split one with two more holes, drilled, tapped, and loc-tite added at 120 degrees apart. Have seen these do self destructive behavior, not good!

My $0.03 worth,

Hank


Wayne Sheldon
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Re: Pin u-joint

Post by Wayne Sheldon » Thu Feb 27, 2020 8:00 pm

As Scott C says, "It's simply the proper way to complete the job."
But lets make it less (or maybe more?) simple.
While in "theory" pinning the U-joint may not be necessary? People think that because the new and improved (actually one of the few "improvements" that I actually endorse!) pinion bearing does set both forward and backward thrust/lash, pinning it shouldn't be needed? However, NOT pinning it does allow some float forward and backward of the U-joint itself. Something it was not intended to do. How much float? Depends upon a whole bunch of factors. Just how well does everything between the drive shaft and the back of the transmission fit? How much wear is there? How much play? Even IF everything fits near perfectly, there is STILL some room for float! There HAS to be, because the springing of the rear end causes a forward and back motion between the U-joint and the transmission! Without it, every bump in the road would cause the two pieces to try to rip each other apart! So, the U-joint WILL float! Just how much? Gravity will ALWAYS try to move the U-joint back. Certain torques and other stresses will try to move it forward. Depending on the amount of angle between the engine and the driveshaft, the U-joint will TRY to center itself. So there WILL be a constant struggle any time the car is being driven to push the U-joint all over the place. If everything is snug? The movement may be slow, but it WILL still happen, it HAS to, because anything that causes ANY shift will force the U-joint to try to re-center itself. So even IF everything is snug when you assemble it? It will NOT stay that way! It will very slowly begin making little noises that you will not notice, and you may not notice them getting very slowly worse. The shoulders that the U-joint will begin hitting, will begin to get beaten back, therefore allowing the U-joint MORE room to move. More room to move will allow it to move more, and faster, and wear even more, and even faster.
Someday, someone will take a ride in your T, someone that knows what a T is supposed to sound like, and wonder what that noise is. (That is what happened some years back to a friend of mine!) Or, you may find yourself on the side of the road waiting for a tow. (I heard about that one.)

Not only should the U-joint be pinned? But even though in theory the thrust is not needed, some effort should be made to confirm that the U-joint is near the proper rearward thrust position, and properly centered in the ball. Otherwise, IF the U-joint winds up too far forward because the driveshaft front bushing isn't properly set or face-reamed? The U-joint may be too far forward and again, it will TRY to center itself, only to cause a fight between opposing stresses and excessive U-joint wear. If something did not go together right? The best time to find it and fix it? Is before the rear end is installed and driven a few thousand miles.
If everything else is good and the pin is handy? It shouldn't take more than about fifteen minutes to check and pin the U-joint.


Jerry VanOoteghem
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Location: S.E. Michigan
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Re: Pin u-joint

Post by Jerry VanOoteghem » Mon Mar 02, 2020 7:16 pm

Haroldc30 wrote:
Thu Feb 27, 2020 5:04 pm
Hello everybody. When using adjustable pinion bearing is it necessary to pin the u-joint.Thanks in advance Harold

Yes.

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