EDITOR NOTE: This is a reprint of a series entitled Just the Tip authored by Thomas Brobst. His ‘make-do-with-what-you-got’ and ingenuity makes for interesting reading and maybe help a poor soul out of a perplexing repair. See if you agree with me this is fun reading.
Just the Tip
Tip #6
Hello again fellow MG and British car connoisseurs. I have a new tip for just in time for the holiday season….my Christmas present to you, haha. So, this afternoon I'm in my garage “putzing” around on my MGA and I noticed the parking brake only seems to work on the left rear wheel. I put it up on the lift to check to check it out. I adjusted both rear brakes and then the parking brake cable adjuster. And now both wheels grab when I put the parking brake on but I'm at the limit of the parking brake cable adjuster. That is to say, underneath the car, in the middle, where you adjust the parking brake with the big hex nut on the end of the threaded stud on the end of the parking brake cable….the nut is turned all the way in as far as it can go. And even then I still have to pull the parking brake handle up farther than I would like. This is the classic parking brake cable stretch or so it seems. So, what to do? Buy a new parking brake cable? I might have done that but how do I know it will solve the problem for certain after all that work and expense...not to mention having to wait till next weekend to finish it? I could install one of those “JC Whitney” style cable “shorteners” that use a U-bolt to “eat-up” some cable length. On my resorted “A”!? No way! How about this…..if I can lengthen the outer sheath of the parking brake cable I would effectively shorten the cable itself. If you can’t raise the bridge lower the river, right? Working at the parking brake cable bell-crank on the back of the rear axle I saw a way to add a cable sheath spacer between the end of the sheath and the bell-crank trunnion.
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Fig 1—Spacer made from 3/8” OD steel tubing
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I selected a piece of steel tubing I had laying around that was pretty much the same diameter as the cable sheath. I would have preferred thick walled aluminum tubing but , alas, I couldn’t find that in my junk bins. Using my trusty band saw I cut a length about three quarters of an inch long and then cut a lengthwise slit about an eighth of an inch wide to allow it to fit over the stranded cable. Next, I pulled the cable sheath away
Fig 2—First Spacer installed over cable.
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from the trunnion and inserted my newly fabricated spacer (see Fig. 2). With a pliers I squished the spacer to close up the gap so it wouldn’t fall off and also so it would fit into the counter-bore that the cable sheath normally fits into in the side of the trunnion. Of course, since I'm a hack, the spacer was a tad too large to fit into the counter-bore. Nonetheless, I figured it would still work so I tested it.
With the cable adjuster re-adjusted it did, in fact improve things but it still used up too much of the adjustment for my satisfaction. So I made a second spacer. In this one I cut the slot
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Fig 3. Second spacer installed into trunnion counter-bore.
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a little bit wider, maybe 3/16 of an inch, so it would crimp down further. Sure enough, when I installed it in between the trunnion and the first spacer it fit nicely into the trunnion counter-bore. (Everything works better the second time, right?)
Why did I fell it was important for it to fit into the counter-bore? It was in the hope that it would help keep the cable sheath aligned and possibly reduce the likelihood that the spacers would abrade the stranded cable itself. If you look at the last photo you'll see that with the parking brake engaged the cable and the spacers all line up very nicely. I think that that second spacer kind of did the trick. My adjustment is now shy of the middle of the adjuster and the parking brake handle engages at a perfect, low height and feels nice and strong.
So, it took me less than an hour and I didn't have to spend any money! Sometimes things just seem to work out. Have a great holiday, all. See you in the new year.
~~ Tom Brobst
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June 2022
