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Technically, the handbrake pads could be removed and reinstalled without taking the handbrake calipers out of the car.
Unfortunately, that won’t do any good, because to install new (thicker) pads you will need to readjust the self-adjuster
and install a new bronze fork. In other words, the handbrake calipers have to come out.
Do you really need a new bronze fork, or can you just rebend the old one? Well, if the handbrake pads are not being
replaced, you only need to spread the bronze fork a little bit prior to reinstalling, and you will probably get away with it.
If you’re replacing the handbrake pads, though, you will have to spread the bronze fork all the way back to its as-new
shape. Mike Morrin says, “Really bad idea. I have seen a couple of cases where the fork has broken due to metal
fatigue. In itself not a big problem, but both times the rotor was destroyed before the fault was noticed. Always replace
the forks when you have the hand brake calipers off. They are cheap.”
When you go to removing the pads from the handbrake calipers, the ROM, Section 70.40.04, says “remove nut and
spring washer securing pads to brake pad carriers, remove pads.” The Haynes says the same thing in Chapter 9,
Section 18, step 10. Removing that nut and spring washer is unnecessary; merely loosen it two full turns and the pad
will slide right out, leaving the bolt, nut and washer loosely in place. They even provided a little hole at the top center
of each pad to make it easier to grab and pull out. Of course, the new pads come with new screws in case you want to
replace them, but there’s really no need unless you strip them or something.
Just getting the nuts loose may be a challenge, though: The nut is 0.325” (8.25mm) across the flats. This isn’t even a
standard Whitworth size! Craig Sawyers says, “The nuts that secure the handbrake pads to the arms are 2BA. And
only a 2BA socket will get in there to remove the nuts.” Paul Burke says, “BA stands for British Association - believe
it or not. BA threads start at size 0 (zero) which is the biggest, and the bolts and nuts get smaller as the number gets
bigger.”
Well, at least you know what to look for. This author used an 11/32” socket which worked but didn’t fit too well; a
21/64” would have been better, if such a thing exists.
The bolt that this nut threads onto has an unusual head, but the threads are standard 10-28 fine thread. So once you get
those weird nuts off, you could put normal-sized nuts on to replace them -- but that might not work well, either. The
nut on the outboard side fits down into a well, and installing a nut with a larger 3/8” hex will probably mean you can’t
get a socket or wrench on it. This author found an excellent solution: the nuts used on military jet aircraft are extremely
high strength and high temperature, yet they are very tiny and require a 12-point box end wrench or socket to install. If
you can find a source for such nuts, they are highly recommended for this application. And you can leave the spring
washer out, since the military nuts are self-locking. You will need to find 12-point sockets or box-end wrenches in 1/4”
or 5/16” sizes; Snap-On makes them. I can guarantee they’ll be easier to find than 2BA -- at least here in the US.
The facing of the handbrake pads is a rectangular shape with a corner cut off diagonally. The end with the corner cut
off diagonally must go towards the rear of the car, or away from the pivots on the main caliper.
All agree on one important point: make very sure the fingers on the bronze fork are correctly in place in the little holes
when it’s all together. If one has slipped out, the handbrake pad will ride against the rotor, and this will damage the
rotor itself in only a few hundred miles.
HANDBRAKE CALIPER REBUILDING: Jan Wikström says, “The self-adjusting ratchet mechanisms in the pad
holders are quite likely to be clogged with semi-carbonized grease and dysfunctional; open the pad holders up, clean
out the ratchet mechanism and grease very lightly with high-temp grease or MoS
2
(molybdenum disulfide). Drowning
them in grease as the factory did is just silly; the ratchets may rotate one turn every few months and don’t really need
lubrication.”
Mack Kamna describes rebuilding the handbrake calipers on Jaguar inboard rear brakes: “In the past my parking brake
lever had to be pulled quite a ways to be effective. I found the self-adjusting nuts to be galled up with dry grease and
very tight on adjuster bolt threads. I cleaned them up and dressed the gear teeth with a small file, then greased both the
adjuster bolt threads (using C5A, anti seize), and the adjuster nut gear teeth (Hi-temp brake grease). I then installed the
handbrake mechanism assembly with new retraction plates, and adjusted the handbrake “system” per the manual.
When I pulled the handbrake lever, you could hear the adjusters smoothly clicking, and the pad assemblies tightened