U-Joint removal

[chickenwafer]

Hey everyone, as you can see, I'm new here but not to Z cars, I have been surrounded by them all my life.

Anyway, to get to the point, I was wondering if anyone out there had replaced the stock U-Joint on their 260z (or 240/280) and how difficult it is. What tools are required? How much time? I'm looking at getting the MSA Spicer oversized u-joints to replace my old rusted ones. Any input would be great- thanks in advance.

Dave

[71zman]

Yep, I changed more U-Joints in Z's than I care to remember. . The tools required are: 1) a big vise (BIG) 2) a sledge hammer, 3) a socket set that you aren't too fond of.4) a punch or chisel

So the process is:

1) Remove the half shafts. They are 14mm bolts, use a boxed end wrench so you don't strip the head.

2) Put the half shaft in the vise and secure so you can see the U-Joint. Next tap out all 4 retainer c-clips on the inside of the U-Joint cap

3) Again, with the shaft secured in a vise and the shaft side U-Joint going up/down, pound down on the u-joint to knock the bottom cap out. Turn the half shaft 180 deg and pound the U-Joint the other way knocking the opposite cap out. Repeat the process with the other part of the U-joint and flange.

4) Get new U-Joints out of box and take off caps on opposite sides. Fit both the caps on the outside of the shaft flange and set the middle part of the U-Joint in place. Put the whole assempbly in the vise (this is why you need a big one) and press fit the caps inward toward the middle part of the U-Joint. Be careful not to disrupt the needle bearings inside the cap. I usually set the middle part in the cap that is moving to hold the needle bearings in place. Also be careful to keep the caps going in straight so they don't bind. Once the caps are close take you socket set and find one that is about the size of the cap in diameter. Open the vise and put the socket between the cap and the shaft and close the vise again using the socket to seat the cap far enough in so you can see the C-clip ridge on the inside of the cap. Put the C-Clip in and repeat socket trick on other side. Do the same to the other half of the Ujoint.

5) Always replace both U-Joints at once

6) When replacing the shafts in the car, use the Emergency Brake to hold the shaft in place to put the final tightening on the bolts

:classic: :classic:

[26th-Z]

You can actually use the vise and socket method to press out the U-joint cup by placing the drift for one cup in one side of the jaw and big spacer over the shaft flange on the other jaw. Closing the vise will press out the cup to the spacer side. This avoids the mistakes associated with beating things with a hammer, like bruised fingers and broken flanges.

[Bambikiller240]

Harbor Freight sells a kit of (basically) "C" Clamps and spacers, etc for U-Joint removal. Price is not very high, and IMO it beats the snot out of bashing things around with a hammer.

PS I have used the hammer method and it definitely does work, but there is lots of opportunity to bugger things up.

[71zman]

Well you learn something every day although I can't quite visualize the drift spacer approach. What exactly does the drift and spacer look like? How do you get alignment in the vise?

71zman

[chickenwafer]

thanks for the help, you guys are great. Hey, Bambikiller240, do you have a link to that site? Thanks a ton guys.

Dave

[Bambikiller240]

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=38335

If you keep an eye on the item over time, it is often sold for less than the price listed on the website

[mperdue]

Hey chickenwafer,

Something to be careful about when putting it back together is to make sure the rod shaped bearings don't fall out of place and get smashed. The u-joint is basically a cross with a cap on each end lined with bearings that are held in place with grease. When I was putting mine back together a few of the bearings got knocked out of place and crushed when I continued pressing in the joint. I had to replace the ujoint. But in the end it wasn't very difficult. If you have the right parts for pressing it's fairly easy.

Oh and if you're considering changing the boots on the half-shafts at the same time you might wan't to reconsider. That was a VERY difficult operation as you have to take the whole half-shaft apart. The cir-clips are killers and the half-shaft is full of little pieces that are easy to drop or put in wrong. It took me and 2 other guys at a professional drive-shaft shop about 2 hours to do it right.

Michael

[beandip]

One more thing IMPORTANT !! Be sure to lube the u-joint. At the factory the bearings in the caps are greased only to hold the needle bearings in place the rest of the u-joint is dry so give the fitting some grease just intell you see the rubber seal start to swell and stop. If more grease is applied you can blow out the seal and the joint will throw grease out.

[santamaus]

My U-Joints are finally going, and I'm happy to have found this thread. A question though--are there caps over the c-clips? I've looked at the U-joints, and don't see the aforementioned c-clips, and the shop manual is about as helpful as a soggy noodle. I also don't see any mention of dust covers or anything in the Black Dragon catalog, and I think I got most of the road grime off.

Is there a method to removing these covers as well (do I just press *those* out)? According to the instructions above, do I remove the caps from the U-joint (roller bearings included), and apply a bunch of all-purpose grease inside there? Is the center section so small that it easily fits inside the yokes?

Thanks in advance!

Chris

[=Enigma=]

Chris,

The circlips that hold the u-joint caps in place are found on the inside of the flange rather than the outside like some others. They are not covered in any way and clearly visible if you remove all the dirt and grime. You can pry them off fairly easily with a screwdriver once you figure out how to do it.

Once you have all the circlips off, you can then use a vise and some spare sockets or the Harbor Freight U-Joint tool to remove the u-joints from the flanges. See the link below for a pic of this process being done on a Jeep driveshaft. You'll see the circlip removal and the use of the Harbor Freight u-joint tool.

http://www.stu-offroad.com/axle/ujoint1/u-joint-1.htm

[santamaus]

Awesome! Thank you very much. Wish me luck!