=
> Followup...
> =
> today I took the rear brakes apart again to replace the rear wheel
> cylinders that I bought on Monday. I figured while I had it apart I
> would clean and paint the backing plates (didn't do that before, in my
> hurry to get the car on the road.) Here's where I found something
> interesting; on BOTH backing plates, all of the little "pads" that the
> shoes ride on were in excellent shape, EXCEPT two of three for the
> primary shoe - the top one by the anchor pin and the bottom one by the
> star wheel were deeply grooved. Again, this was on both sides, and the=
> wear patterns were similar. I wonder if maybe someone had the drums cu= t
> and whoever did it left a little "spiral" on the wearing surface and th= e
> shoes were chattering? =
The top and bottom tend to get the grooves because the movement of the shoe tends to follow the direction of the edge of the shoe. At the middle it's is moving at 90=B0 to the edge. The problem tends to develop when you stick on new shoes and the groove is in the wrong place (the edge of the shoe is riding on the edge of the groove instead of the middle). You will probably notice the shoes have a little wrinkle in the edge where they contact the backing plate. If designed right that goes along way to spread the load and keep the edge from knifing into the backing plate. But some designs tend to cut in worse then others. Old Ramblers come to mind.
who knows... Now I wouldn't have noticed this
> if I hadn't taken the backing plates off the car, as those pads are
> difficult to look at when you're bending down to look under the quarter=
> panel. The middle one by the hold down (the one that your eye is
> naturally drawn to) was fine. I don't have any explanation for this,
> but I went ahead and laid a bead of MIG weld down on there and ground i= t
> back smooth. I am fairly certain that this issue does not exist on the=
> fronts as I cleaned and painted the front backing plates when I rebuilt=
> the suspension.
> =
> The paint on the rear backing plates is drying now so I will reassemble=
> tomorrow and see if it did anything. Will bypass the anti-creep valve
> before bleeding.
> =
> I've put a few more careful miles on the car, and since I cleaned
> everything real well last weekend I can see exactly where the shoes are=
> contacting the drums. The secondary shoes are making maybe 50% contact= ,
> but the primaries a lot less, almost as if the grooves really were
> holding the shoes up. =
Which 50% is making contact? Is it in the middle? one end? or both ends? That doesn't sound good, it shouldn't take much wear to get 100% contact if they are at all close to the right size to begin with.
-jim
Also it may be my imagination but even after
> putting maybe only 50 more (careful!) miles on the car since the last
> time I posted the rears feel less "grabby" - I haven't had the brakes
> lock up in traffic at all, although when I really tested them in front
> of my friend's house the rears still locked before I thought they
> should. So I am wondering if really the fact that the rear shoes aren'= t
> completely worn in is the main problem. Well, anyway, we will see if > this helps...
> =
> I haven't pulled the driver's side front yet since my original post; I
> am curious whether or not it is still getting more dust than the pass.
> side. However, in retrospect, I think most of the dust that I saw may
> have been rust wearing off the drum - IIRC that wheel had a completely
> seized wheel cylinder when I got the car and that drum had more surface=
> rust on it than the others. If I have time tomorrow I will probably
> pull it again just to make sure nothing is amiss.
> =
> nate
> =
> (I just want to drive my car! Is that too much to ask?)
> =
> --
> replace "fly" with "com" to reply.
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