[xj-s] emergency brake / handbrake weirdness from hell

Hi folks,

well I am about to chuck this whole car because of what I have gone
through with the handbrake.

I have the JDHT CD and tried for several days to service my
handbrake before finally giving in and taking it to a mechanic.
They held onto my car for 5 days and didn’t do jack to it. I
finally called them and the guy tells me it’s going to cost $2,000
to repair. He said the rear discs are ‘‘paper thin’’ and need to be
replaced along with the handbrake calipers. Of course, I said no
way and went and got it. The car (1990 XJS) only has 78 k miles and
the discs looked far from paper thin when I was under the car. I
haven’t measured them yet but bought a micrometer and am confident
they aren’t less than the .4’’ spec. The regular brake system works
just fine.

A weird thing I have noticed is that the handbrake holds fine
against the car being in reverse gear, but slips when the car is
placed in drive. That seems very strange to me since I know reverse
gear typically has more torque than drive. Anyone know why that
would be happening? Oh and the handrake pads are about 3/8’’ thick
and appear new so they aren’t the problem from what I can tell.

It’s really driving me nuts since this emergency brake problem is
the only issue preventing my car from passing inspection here in
Texas. Also, no auto parts stores seem to carry OEM or aftermarket
handbrake calipers, and I haven’t found them at JagGraveyard or
anywhere else either. If anyone knows where I can get them or at
least a rebuild kit I woyuld really appreciate a heads up.–
ckimrey
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In reply to a message from ckimrey sent Thu 28 Feb 2008:

Whoa whoa whoa buddy,

Before you chuck that car…

First and foremost, check your cable. I know that it seems weird
that in reverse it holds, but that may be because of the rotation
of pads vs. rotor wear/ or some other physical b.s. The matter of
fact is that your cable itself is faulty. I am fairly certain
based on your explanation.

You need to tighten it in order to make it work. First you need to
jack up the car and remove the rear wheels. By the way, does the
car slide forward when you just pull the brake to engage it, and
not let the lever back down(you know how wne it is engaged, it
still comes down.)? Don’t let the lever come down, does it ingage,
if so, its the mechanism, if it is still rolling, it is something
with your cable. Disassemble the handbrake area(may need to take
out the seat) and get to the cable. You may tighten it there too,
BUT… You may also be able to tighten it at the wheels. I
haven’t looked there like ever, and have’t seen how the cable works
at the wheels. But basically, it is probably the combination of
pads a bit thin (not paper thin) and the cable being loose. You
can also remove the cable (it was threaded there in the first place
after all) But yeah, check the cable.

Good luck, read other posts too as far as tightening cable at the
wheels–
Gleb
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In reply to a message from Gleb sent Thu 28 Feb 2008:

It has been a while since I played with my handbrake system
but if I recall…There is a self adjuster that most likely
is frozen. Also check the cable. If the pads are thin or the
handbrake caliper is out of adjustment it will not work
properly. The system is really simple but is hard to see
especially without a lift.

Is there nobody in Texas here that might be able to help or
refer a decent shop.

Keep us posted.–
Greg 1985 XJS HE DANA rear
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In reply to a message from Gleb sent Thu 28 Feb 2008:

thanks Gleb,

well yes I have worked with the cable quite a bit. Initially it was
extensively rusty at the adjuster and the adjuster nuts would not
turn. I removed it and cleaned it all up and it now works as it
should. Tightening the cable helped get it to the point where it is
now- namely the brake holds when car is in reverse gear. When the
car is in drive it is apparent the brake is trying to hold by the
sound of the pads on the disc, but it just doesn’t hold tightly as
it does if set against the reverse gear. Further tightening of the
cable only serves to make the travel of the handbrake lever
progressively shorter. I got it to the point where it would only
click twice before going no further. Still the braking was no
better so I backed it of to get 3 clicks (4 if really pulling
hard). If I put it in drive and keep the button pressed while
really pulling up hard I can get it to hold the car, but we’re
talkin like 50 lbs pulling. I’ve read Kirby’s book on this issue
and cable tightening as a means to get better braking hold is to
him a big no no.

I’m pretty sure it’s an issue of the adjusters in the handbrake
calipers being rusty or gummed up with old grease. Man though I
tried for days to try and get a wrench on them to no avail. It
seems the only way to get them off is to drop the rear end and that
is going to a whole new planet for me as a weekend grease monkey. I
was freaked out enough as it was being under there with the car on
stands. It is unbelievable that it takes that much trouble to
service what is essentially a glorified bicycle brake.

Beyond that I can’t seem to find the parts to replace or rebuild
them should I ever get them off. There is no way I am going to pay
2 grand to fix a handbrake though.–
ckimrey
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In reply to a message from ckimrey sent Thu 28 Feb 2008:

Where in Texas are you??? There are some good shops in the DFW
area I can recommend. Most of the XJ6/XJ-S rear calipers don’t work
properly because no one uses the *&^%$## handbrake when they park.
My wife had a 1972 XJ6 that would lock the rear wheels at highway
speeds with the handbrake but she used it EVERYTIME she parked the
car!!! The ratchet mechanism grease gets hard and to compound the
problem, if the wear distance is too great then the ratchet
increment is greater than the cable pull and won’t ‘click’ to the
next tooth. The calipers need to be disconnected from the cable and
pulled and pushed to the extreme positions until the ‘click’ is
heard in both directions. I use a long prybar to lever the arms
back and forth. If this procedure fails then the other way is to
remove the split pins and turn the adjusters with a flat blade
screw driver (good luck as the exhaust is in the way) and reinstall
the pins. I have never failed to adjust a handbrake caliper and I
have never charged more than several hours labor if I had to remove
the split pins and turn the screws by hand. If the rotors or pads
are worn beyond limits, then the price goes higher as the job
becomes more difficult (not $2000.00 difficult) but I WOULD FIND
ANOTHER SHOP. bob–
The original message included these comments:

finally called them and the guy tells me it’s going to cost $2,000
It’s really driving me nuts since this emergency brake problem is
the only issue preventing my car from passing inspection here in
Texas. Also, no auto parts stores seem to carry OEM or aftermarket
handbrake calipers, and I haven’t found them at JagGraveyard or
anywhere else either. If anyone knows where I can get them or at
least a rebuild kit I woyuld really appreciate a heads up.


Owning and Repairing Jaguars Since the Early 70’s
Decatur, TX., United States
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Since you have the JDHT CD, refer to Section 70.40.04 in the Brake
Section. That section deals with the replacement of the handbrake
pads, and proper adjustment of the “adjusters” in the handbrake
calipers themselves. As described in that section, you have to
manually move each of the levers in an inboard direction repeatedly
until the adjuster ceases to click when you pull the lever. At this
point, you have the calipers closed to the point where the pads are in
contact with the disc.

If you cannot adjust one or both of the calipers in this fashion, then
something is wrong with the adjuster mechanism, and you should remove
the caliper(s) to repair the mechanism. You indicate in your later
post that you have repeatedly adjusted the cable, so that is NOT your
problem. You have it properly adjusted if the handle clicks 3 to 4
times when you pull with a normal force to get it to full engagement
position.

One other thing – are you sure all 4 pads are properly in place? It
is not uncommon for one or more pads to become dislodged from the
caliper, and if this happens, you lose proper clamping force.

George Balthrop, Clifton, VA USA
85 & 89 XJ-S Coupes; 89 XJ40 VDP-----Original Message-----
From: ckimrey molbio1@yahoo.com

I have the JDHT CD and tried for several days to service my
handbrake before finally giving in and taking it to a mechanic…
A weird thing I have noticed is that the handbrake holds fine
against the car being in reverse gear, but slips when the car is
placed in drive. That seems very strange to me since I know reverse
gear typically has more torque than drive. Anyone know why that
would be happening? Oh and the handrake pads are about 3/8’’ thick
and appear new so they aren’t the problem from what I can tell.

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In reply to a message from motorcarman sent Thu 28 Feb 2008:

thanks bob,

I am in the Austin area so if anyone knows someone good here for
this I’d love to hear from you.

Yeah I am certain you are right that it’s just an issue of gummed
up ratchet mechanisms in the calipers. That is something I know I
can deal with, but my god getting to them is a nightmare.

Maybe I am just being to skittish about dropping the rear end
myself. It just seems so extreme, but maybe that’s just because I
have never done it. I’ve read on here about people doing it in a
couple of hours, but I get the impression alot of this forum’s
members are damn good mechanics. I’m just a dabbler. Anyway how is
it done with stands and such? I really would rather not be crushed
under the differential ; )–
ckimrey
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In reply to a message from ckimrey sent Thu 28 Feb 2008:

ckimrey, yes you need new disks, also new handbrake pads, not
new handbrake calipers, the cable is fine. bring the car home
, drop the cage, youll be much better off.–
cardogs - Ken Jakub '91 XJS V12 convertible
pittsburgh, pa, United States
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