The first order of business was to take everything apart. That was just straightforward mechanic work, but the brake drums were a trial. It turns out that MG designed the hub that holds the wheel bearing as an integral part of the drum. The internet was full of stories about how hard it is to get apart. Back in the day, MG dealers had a special tool, but those are long gone. I wound up creating a wooden extension that bolts to the brake drum and allows a modern two-jaw puller to be used:
That got the drum off, but it also left the inner bearing behind. Again, the internet said that usually happens. More work with the puller removed that as well.
Once it was all apart, Troy Nace and I did hours of work comparing the components on hand (both new and old) with the parts diagram, and attempting to assemble everything exactly right. Finally the uprights with the spindles were correctly assembled with all the spacers, washers and grommets in the right place, and I could start thinking about the brakes.
First order of business was to reinstall the bearings in the integral hub in the drum, and for that I took all my parts over to Phil Oles' house. He has a magnificent old arbor press that made quick work of it - once we cleared a path to it!
I was sure the car would be on the ground very shortly, and the passenger side brake assembly came together without a hitch. It would spin freely, and the brakes adjusted just as one would hope. But when I assembled the driver's side, something was binding! Before I could get the large castle nut tightened, the drum seized and would not turn.
I backed away to ponder. In conversation with Charlie Baldwin, we came to the conclusion that I should remove the brake shoes and adjusters to make sure the binding wasn't there. A further conversation with Kelly Williams gave me the suggestion to use Dykem machinist's blue dye to ensure the bearings were seating properly. I did both things, and all I gained was the knowledge that those two things weren't the problem.
By this time, I had had the hub off at least 6 or 8 times, and I was being bad and tapping the bearings back in with a mallet because I didn't feel like driving over to Phil's. It was time for a press at the Grant Street Garage! John Zimmerman helped me pick up a modest 12 ton press at Harbor Freight, and I built a rolling base and assembled it.
Incidentally, those wheels are the style to allow me to drop the base to the floor for stability, and they are also removable. The press works great!
Good thing, because I used it about a dozen times since it came together. My next check was to press the bearings out of the hub so that I could assemble the inner stack of components to ensure a bearing wasn't binding as things were tightened. All was OK.
Back apart it came, and I decided it would be OK to reinstall the brake shoes. Here's a picture to remind me how the springs go:
It was clear the drum or hub was hitting something, so I began a iterative process that went like "take it apart, put Dykem on some surfaces, press the bearings back in, put it back together, and see what hits." After a couple of hours of that dance, I finally found it - the back of the hub was hitting something. The arrow shows the rub:
The only culprit I could see was the nuts that hold the brake backing plate to the spindle. I found evidence of an old hit:
Easy to test for that - I removed the nut and bolt entirely, and tried again. Then I had a new hit! You can tell it's fresh because it's shiny.
I tried relieving the edge of the hub a bit with a rotary stone in a Dremel tool, and it made it better, but there's a bit of rubbing still. Tomorrow I'll get it all straight, and then I'll be back on track.
This is another place where something that clearly had worked decided to stop. It's not a big surprise, because all the component were off the car and were mixed pretty thoroughly. Tolerances stack differently every time you reassemble something, and I found a combination that didn't want to fit!
On the plus side, I will never fear pulling those brakes apart again, because I've done it 20 times in the past week!
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