A common complaint about the MGB is the collapsible steering columns fitted from model year 1968 onward. It seems that all too often they wear out long before the rest of the car does, or at least, when the rest of the car is repaired, the steering column is ignored. Often it is because the factory never offered any replacement parts, so when they wore out, you either had to find a replacement column or you just had to put up with the worn parts.
The ball bearings used from the factory were of the worst design possible. They were cheaply made and of an oddball size that was/is not readily available Bearing replacements kits are now available from GEM Enterprises, elsewhere on this site, for a reasonable cost, so there is no reason to put up with a sloppy column. [Ed. Note- these bearing kits are no longer available]
Another of the problems with these columns is the telescopic joint in the steering shaft. In order for the steering column to be able to collapse in the event of an accident, both the outer steering column housing and the inner shaft has to be able to collapse. The outer housing is perforated to provide for easy collapsing. The shaft is designed to telescope within itself upon a collision. The shaft itself is made of two pieces. One, the outer tube is basically a hollow tube with a modified socket to receive the inner shaft. The inner shaft is solid, and threaded to attach the steering wheel.
The inner shaft has two flats formed on the sides to match the outer tube. There are two recesses around the inner shaft in the area where it fits into the outer tube. From the factory, these recesses were filled with a tough plastic to act as friction material between the inner and outer shaft. Often if someone disassembles the steering column, the plastic is broken into pieces and cannot be reinstalled as it originally was. Reassembling the column without this plastic adds rotational play in the steering shaft and allows metal to metal contact between the inner and outer steering shafts. Left alone, this will eventually wear the shafts to the point of failure.
One solution to this problem is to drill two holes through the inner and outer shafts and install 1/16" split cotters. This will allow the shaft to hold together as one piece until a impact causes the cotters to shear. When the cotters shear, the column will collapse as designed. The downside to this method is that the cotters can also shear when you do not want them to shear. If one uses the steering wheel removal method of backing off the steering wheel nut and hitting the shaft/nut with a big hammer, you will likely shear the cotters, requiring steering column disassembly and replacement of the cotters.
Another solution would be to weld the two shafts together, but this would eliminate any possibility of the column collapsing as designed. I have never believed that safety devices should be over-ridden so I will not recommend this method.
The third method it to replace the plastic that was injected at the factory with something very similar. To do this, I completely disassemble the steering column. The two shafts are separated and the old plastic is removed completely. On the outer tube, there will be four small holes, about 1/16" in diameter. I use a center drill to taper two of these holes to act as a socket for the nozzle of my hot glue gun.
With the two shafts back together and in their proper positions, I heat up the shafts with a propane torch or a heat gun. The idea is to heat the metal up to around 165 degrees so that the hot glue will flow all the way around the recesses before cooling and solidifying. Before you do this, be sure that the bottom steering column bearing is in place, because after the shafts are assembled, the bearing cannot be installed.
With the shafts good and warm, and the glue gun warm as well, I insert the nozzle into one of the funnel shaped hole and force the melted glue into the hole and the space between the two shafts. When the cavity is full, glue will start to ooze out the hole on the opposite side. I then repeat the same technique for the second hole. I allow the shafts to cool, then remove the excess hot glue from the outside of the tube.
The steering column can now be reassembled with new bearings and will be as good as new!