Thursday, April 14, 2016

Replacing a U-Joint on Scarlett

Disappointingly, even though I had been injecting fresh grease into each of Scarlett's U-joints every 2500 kilometers, I noticed during the 35k km services that the one nearest the sidecar wheel was loose and beginning to fail.

The replacement U-joint used to be readily available at the local AdvanceAuto parts store, Neapco 1-0300, but the supply has apparently dried up.  None of the auto parts chain stores had it or something similar.

Ordered two online, and got them on Monday of this week.  Finally got around to doing the replacement myself after dithering whether or not to do it or have someone do it as I remembered it being a bit of a PITA.

I'd reviewed the below video by fellow URALista Craig H.  aka S 854 on  He made it look pretty easy and overall, it was.  But my karma dictated that I run into some "learning experiences".

Overall, yes, you can do it with all the components "in situ".  It took me much longer than I figured on due to my "learning experiences" listed below though.  Still, it's done.  Next time, probably borrow the use of a hydraulic press or buy one before then.

Yes, a hydraulic press is a better choice rather than beating metal with metal.  Yes, it's a bit "shade tree mechanic".

Learning experiences:

1.  Get and use a decent set of snap ring pliers, not the crappy one with multiple pin types from Harborfreight.  

2.  Took me a while to figure out how to remove the snap rings which were different and thinner than the older ones shown in the second video.  You need, besides a decent set of snap ring pliers, a thin bladed fat tip screwdriver to pry up one of the end points that you've compressed towards each other, then once pried up, use needle nose pliers to pull the ring out.  Yep, you'll probably bend the old snap ring, making it unusable.

3.  Best socket to use is the 17mm socket, it fits best to drive the cups inward.

4.  Due to the awkward location, several methods were tried and discarded to apply force to the U-joint cups to get them into the right position.  Destroyed a long wooden post, ruined a 3/8" drive extension, and best of all hit myself in the hand with the BFH at least three times.

5.  Best learning experience?  I was down to my last snap ring to be put in, but the cup just wouldn't go far enough into the yoke for to me install it!  I pounded on it and pounded on it to no avail.

Finally, during dinner, it occurred to me to ask a neighborhood friend, Chip, to help pound the cup in as I apparently was too weak.

Chip readily came over and after some examination he said that one of the roller bearings had probably fallen from the inside rim of the cup and was blocking the progress of the last cup.

We drove out the cap in question and damn if there wasn't a roller bearing laying there.  Dammit.

So, bearing retrieved and put back into place, some careful replacing of cup onto the U-joint cross, some careful hammering and Chip got the last cup into place and I put in the last snap ring.

I still have to inject grease in but Chip recommended I not use what I had, but to use synthetic grease instead so I'll have to go buy it.

6.  Don't use try and push the cap initially onto the yoke mounting hole, use a turning motion with steady downward pressure, ensure its level, then light taps with the hammer.

7.  If progress isn't evident, try slightly moving the yokes about, sometimes the angle change helps.

I see a hydraulic press in my future:

source: Harborfreight

24AUG16: Update.  A fellow Uralista, Stagewex on SovietSteeds found what is a comparable u-joint to the Neapco 1-0300.  It's an Autozone sourced u-joint, the Duralast 1-0300DL for $9 each vice the Neapco u-joint which I paid $27 each from!


RichardM said...

I was hoping that regular greasing of the u-joint will extend it's life. I guess not. I wonder why?

I can't count the number of times that I wished I had a press.

Ridertips said...

Just checked my old Interceptor suspension :)

redlegsrides said...


I am still sure that regular greasing will increase the life of the u-joints. I'm hoping it was just a defective u-joint. Or, I need to ensure grease is oozing out of every thing cup seal each time. Maybe rotate the u-joint while greasing?


When I clicked your link, thought I'd gone to a "weight loss" spam site, turned out to be just an AD....

RichardM said...

In order to use a hydraulic press on that u-joint, you would need to remove the stub axle from the sidecar swing arm. I had tried doing that last June but the bearings wouldn't come loose from the swing arm. The solution would have been to remove the swing arm and press out the axle and bearings but that probably would've damaged the bearings. I decided to leave it to be done at Raceway in July.

redlegsrides said...

It was exactly your experience dealing with the stub axle that pushed me in the direction of doing the u-joint replacement "in situ", RichardM!.