[Roadsters] Can you help diagnose a brake problem?

[John F Sandhoff]

> I *gingerly* apply the brake on a slight incline.  It does NOT hold.
> There was never a "give" or a sign that any weld or repair gave way.
> IMMEDIATELY after attempting to set the brake, the rhythmic scraping
> returns!

The parking brake setup is really pretty simple. A cable, an adjuster, a
pivot point and a couple of solid rods...

Since you get the scraping upon application, I'm 'assuming' the linkages
are all working. So here's some things that are potentials:

First, I'm assuming the parts are correct. If the shoes are incorrect
(Roadster shoes last I checked were NLA - hint: 510 shoes work), the
pawl that mechanically applies them may not be properly aligned or
even connected...

The rear adjusters are manual - that is, no 'back up 20 times and the
brakes auto-adjust'! This is a foreign concept to youngsters :-) The
shoes MUST be properly adjusted for the parking brake to work!
If they aren't the rear brakes aren't working, but you probably wouldn't
notice 'cause the fronts do almost all the work anyway. So, make sure
those shoes are properly adjusted in the first place (jack the rear end,
in neutral, turn the wheel and have someone gently apply brakes. You'll
see if and when the brakes activate).

After the shoes are dialed in, the parking brake, if the pieces are
all there and working, are an adjustment away. There's a turnbuckle
down there. With the handle down, it gets tightened to just before
it starts applying tension to the assembly.

If you scrape after release, it sounds like you're missing the retract
springs. There's one at each wheen cylinder, between a clamped-on
hook on the activation rod and a hook on the brake backing plate.
It pulls the activation rod towards the cylinder. If this spring is loose
or missing the parking brake won't fully release.

Truth be told, sounds like you need another brake shop to take a look.
This system is simple, but historical. Old timers, or thoroughly trained
youngsters, will have no problem understanding it.

-- John
     John F Sandhoff   sandhoff at csus.edu   Sacramento, CA