Kevin B. Rhodes wrote:
> I just replaced the shoes and drums on my 77ish Spitfire
> and have a couple questions:
> 2. How freely should the brake cylinders be able to slide
> back and forth? Mine do slide, but I would not call it
> freely by any stretch of the imagination.
If you can move the cylinder by hand without having to
use a tool to lever it back and forth, you should be
fine. You can use a small amount of lithium grease on
the sliding plates during assembly to help. Don't overdo
the grease -- you definitely don't want the grease working
its way onto the drum or shoes. Derusting the plates helps a
lot, too. They only need to move freely enough to allow
the shoes to centralize in the drum during braking. There
is a lot of force involved during braking, so the cylinder
doesn't need to move back and forth too easily. However,
mis-centered cylinders can cause the dragging problems you
are experiencing after installing new shoes.
> 3. After new shoes and pads all around I still have just
> a touch of pull to the right on initial application of the
> brakes. Once past that initial tug it stops nice and
> straight. Any ideas?? Possibly related to my not-so-free
> sliding rear cylinders?
I think I know what this one is, as I recently had this
*exact* problem. In my case, it turned out to be a collapsed
left front brake hose.
What was happening is that the left front brake hose was
partially closed, making it resistant to fluid flow. Thus,
when I stepped on the brake pedal, the brake fluid would go
to the right front caliper first, and activate that brake
until sufficient pressure built up to force the fluid
into the left front. Since the right front brake would
be engaged a little before the left, I'd get an initial pull
to the right. However, once significant braking occurred,
the left front would engage as well, and the car would brake
in a straight line. Basically, if one were to try to stop
hard from 30mph in my car without holding on to the steering
wheel (don't try this unless you are *very* careful) the
car would suddenly pull about 10 degrees to the right, and
then continue to brake in a straight line.
I suppose if I were in Triumph marketing, I could try to
sell the above as a "feature" which automatically brought
the car over to the shoulder under hard braking! (At least
in the US!) You can live with this for a while, but the
same pull to the left could be pretty catastrophic! (w/LHD)
My vote would be for a collapsed left front brake hose.
However, I would highly suggest replacing both sides, or
you may find your car then pulls to the left, as they
may both be collapsed -- the left one may just be the
worse of the two...
--ken
--
Kenneth B. Streeter | EMAIL: streeter@sanders.com
Sanders, PTP2-A001 |
PO Box 868 | Voice: (603) 885-9604
Nashua, NH 03061 | Fax: (603) 885-0631
|