U-Joint Tech Day
February 13, 2005 - Elk Grove Village, Illinois

About a dozen members assembled to R&R the universal joints in the MGB propshaft. Most of them had never seen it done before, so there were lots of hands in the pockets for a while.

Click on small images for larger images.- Larger pics average 34KB.

Disassembly wasn't too difficult, just a little tricky. Remove all of the snap rings and tap the side of the yoke until the bearing caps come out the ends. Unfortunately one of the caps was pushed in until it dropped into the middle of the yoke, after which it was a bit of a challenge to get it back into the bore to drift it to the outside. Most of the reassembly seemed to be going okay, until one snap ring could not be installed. On the chance that a needle roller was caught crosswise inside of a bearing cap, it was disassembled for further inspection, a few times. After some careful measurement it was determined that the new U-joint was about 0.004 inch too wide across one axis to allow installation of the last retaining ring. This was apparently a manufacturing error (which should be very rare with these parts). So a hand grinder was employed to take a couple of thou off each end of the yoke at the tip of the male bearing journal, after which the bearing caps would nest a little farther on, and the assembly width was reduced accordingly. Reassembly was then normal with snap rings fitting and seating properly, and all was right with the world (having consumed about 75 minutes for a 15 minute job).
With this "baptism by fire" experience well in hand, the second u-joint was installed in proper order in about 15 minutes with nothing unusual to write home about. Things may have gone a little quicker, but show and tell is important for these tech sessions, and everyone needs a chance to scratch and sniff. By end of session about ten more club members are qualified to change a u-joint without too much fuss. The second picture from left above shows three different u-joint spiders, any of which would fit the assembly, but not all being equal in function. The part on the left which was just removed has a grease fitting dead in the center, which is generally useless when it cannot be accessed in assembly. The part in the middle which we were installing has a grease fitting extending at 45 degrees to one side, which is accessible in assembly, assuming it is actually assembled in the correct orientation. These u-joints will accept grease into the center which is distributed to the four end caps through drilled holes in the spider. If access to the center mounted grease fitting is a problem, you could drill and tap one of the end caps for a short grease fiting, in which case grease will be distributed to all four ends through the same drilled holes in the spider. The part on the right has no grease fitting and is not drilled through the spider. In this case installing a grease fitting on one end cap is a lost cause, as it would only supply grease to a single bearing cap. These u-joints are often advertised as being "sealed u-joint" and/or "lubed for life" like it was a premium feature. What it really means is the life of the part ends when the seals and grease fail, and then you get to install another one. Two of these parts are being returned to the supplier unused.

Photos courtesy of John Schroeder