Adjust brake (anchor pin ?)

[RossL]

I recently rebuilt the brakes on my 55. The eccentric cam for the front shoes was not at all engaged on either side. I read in the manual to check the clearance through the brake drum with a feeler gauge and if you cannot get the specified clearance to do a major adjustment.

Since half of my brake shoes were installed incorrectly (primary shoe in wrong position), I want to go through all of the specs, it seems the last person to work on the brakes didn't know what they were doing.

I tried to loosen the nut for the anchor pin, it was very tight and I could not loosen to enough move the pin. But now when I tightened the wheel the drum is locked (the drum spins fine before the wheel was on).

Now I'm thinking I may have to remove the backing plate to get an impact wrench on the nut for the anchor pin and remove, clean, and lubricate it.

I can see how the eccentric cam works, but I don't see what the anchor pin does. How does this "adjust" (does it move up and down)?

[Rusty57]

Yes, that is a pretty convoluted system because you have 3 points to adjust.

I'm still thinking about why the assembly will not rotate after you install the wheel and tire.

The anchor pin just moves up and down to position the whole brake shoe and spring assembly vertically inside the drum. Based on what I can see the eccentric then positions the primary shoe in or out in relation to the drum. Then the star wheel will adjust the secondary (rear) shoe in relation to the drum.

The tricky part is that the adjustments are not completely independent. So adjustment is an iterative (fancy name for trial & error) process.

Not sure if you have seen this video. https://www.google.com/search?q=Adjsut+ ... 1j0bA,st:0

While he casually mentions this in the video I cannot over-emphasize the need to frequently pump the brake pedal to apply the brakes during each step of the process. That will always force the shoe & spring assembly to center itself with respect to the drum.

I feel for you with respect to stubborn hardware. Obviously I would soak the nut on the anchor pin with rust penetrant. I would then get a long flex handle and 6 point socket on the nut. Just start "bouncing" the handle in both directions and keep increasing how hard you push and pull on the handle. I know this sounds crazy but most of the time with this technique I will hear the nut "crack" in the tighten direction. Once you hear that wire brush the threads and apply more penetrant. Just keep working the nut back and forth.

With respect to the eccentric, make sure you do not move it over center. I think he actually did that in his video.

[DynoDan’55]

Eccentric not essential, apparently, since they dropped it in ‘56 (?). If I remember, I think I just moved it to a neutral location when I last worked on my brakes. Since replacement drums aren’t slotted like the originals, I didn’t bother with the feeler gauge either.

[Rusty57]

DynoDan’55’s post made me start thinking. I don’t know about 1956 but in 1957 the only adjustment is the star wheel at the bottom of the shoe and spring assembly.

So what happens in a ‘55 if the only adjustment you use is the star wheel? I agree that it would be best to move the eccentric so is out of the way.

I’m still trying to think of a reason that installing the tire and wheel clause the brake drum to lock up. My best guess is that there is some type of distortion of the brake drum due to tightening the wheel against the drum. I assume that if you install the lug nots just snug the assembly turns.

[RossL]

I got the nut off the anchor pin and removed and reinstalled the anchor pin with a light coating of anti sieze

From reading the previous comments I may abandon using the eccentric cam but now I’ve got to get the anchor pin installed in the optimum position