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Jeff Berk

wide ratio FS5W71B slipping out of 3rd & 4th

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There is indeed someone making freshly locally machined RH main shaft nuts. 

Now I have to remember where I saw it......

Check godzillaraceworks first....

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Assuming your threads are ok on your old nut, you can also just make a thin shim washer to put between it and the spacer behind it to move the place where the peen gap in the shaft lines up with the nut sleeve in a fresh spot when the nut torques up. 

 

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3 hours ago, zKars said:

Assuming your threads are ok on your old nut, you can also just make a thin shim washer to put between it and the spacer behind it to move the place where the peen gap in the shaft lines up with the nut sleeve in a fresh spot when the nut torques up. 

 

I might just do that. $60 for a nut seems a bit steep. If I still had access to the maker space machine shop I'd try and make some but they're closed until further notice due to C-19. I actually found some M27X1.5 staking nuts but nothing M27X1.0.

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18 hours ago, Jeff Berk said:

I might just do that. $60 for a nut seems a bit steep. If I still had access to the maker space machine shop I'd try and make some but they're closed until further notice due to C-19. I actually found some M27X1.5 staking nuts but nothing M27X1.0.

I did a lot of looking and couldn't find anything M27x1.0

$60 seams really cheap to me when you look at the time it takes, the material and the fact that an M27x1.0 tap starts at about $50 up to $150

I found a piece of 1 1/2" steel hex stock 12" long that would cost about $50 to my door. Could only get 8 nuts or so out of that. You couldn't get me to machine one for $60

Not trying to be argumentative but these one off parts are really expensive to make.

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Just dig in, mentally, to what the nut does, and what the purpose of the crimp over the flat section is for.  It seems mysterious but it's actually very crude.  It's actually a last safeguard that should never be needed.  You could probably torque the nut and never crimp it and 99.99% of the time it would not come loose.  

Also, consider the chemistry of the thread lockers, which weren't available in the 70's.  If you buy a new differential today it will come with thread locker on the bolt for the locking pin.  No special crimps or lock washers even though if the lock pin comes loose, it's disaster for the differential.  I'd do what zKars says above and add some red Loctite for extra peace of mind.  

It's just a nut on the end of a shaft.

https://nylok.com/

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OK, I'm good with the nut issue and I just about have the whole thing taken apart. I could use an opinion on the condition of the 3rd/4th fork condition.

3rd-4th fork B.jpg

 

 

3rd-4th fork A.jpg

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Something seems off center, looks like uneven wear.  If you measure the thickness of the bearing pad it should match the thickness of the other forks.  Is the fork tight on the shaft?

I looked around for pictures and found an interesting transmission parts site.  Might be handy.

https://www.transmissionpartsdistributors.com/fs5w71-fs5w71a-fs5w71c-fs5w71e-fs5w71g-fs5w71h/

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The fork was tight on the shaft (roll pin intact). I've attached closeups of the 1/2 fork (marked "T") and 3/4 fork (marked "C") with measurements. I'm not sure if there is any path forward if the 3/4 fork needs to be replaced because it appears to be NLA. The measurements are widths. I'll send the thickness shortly.

An additional question... The rebuilding kit only came with one set of needle bearings but the transmission has several of them. Should I purchase additional needle bearings and replace them all?

3rd 4th fork C.jpg1st 2nd fork.jpg

 

 

Edited by Jeff Berk

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referring to the above photographs, the 3/4th fork pad thicknesses (top, center, bottom) are 4.11, 5.09, and 4.00mm.

The center pad has a slight stepped appearance on one side. 

The 1/2 for pad thicknesses (top, center, bottom) are 4.55, 4.33, and 4.98mm

I'm measuring the pad thickness as shown in the photograph.

 3rd 4th fork D.jpg

 

 

 

 

Edited by Jeff Berk

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