Berkeleying drum brake issue

The drum brakes on the rear of my car are driving me nuts.

It's no surprise that with wilwood discs in the front, and 2/3 of the weight on the back, that the front just locks up.

My issue today is that the rear drums only seem to be rubbing at the 3 and 9 oclock positions. This makes sense, and I see that if you use them enough they can wear down the 3 and 9 oclock positions enough to get all the shoe in contact.

How long does this take? any way of speeding it up? I have an autocross this sunday that I'd really like to have brakes for.

I have a proportioning valve arriving tomorrow that will reduce pressure to the front brakes.

Those are the correct shoes for sure? I've heard of the wrong pads in the right box before...

Sounds like the shoes are too small (tighter radius?)

Old timers may remember shoe re-arcing (to match the curvature of the drum) but I haven't heard of it in many years.

drums cut over max spec?

We have an arcing machine at work but that doesn't help you.

I don't know which car you are talking about so this may or may not help.

Some drums have an adjustable anchor pin. The big pin at the top (usually) that the shoes pivot on.

If you look at the back of the drum and see a big nut on the back of the anchor pin with a slot or wrench flats on the pin itself, then the pin is adjustable. It's actually on an eccentric.

So, you want to adjust the shoes up so they make contact with the drum, then rotate the drum so you can hear the shoes drag.

Loosen the anchor pin lock nut and turn the anchor pin while turning the drum. You should feel the drum get tighter or looser as you move the anchor pin.

You want to set the anchor pin to make the shoes drag on the drum as little as possible, then tighten the shoes up a bit more and repeat until it won't get any better.

Then lock the anchor pin locknut and reset the shoes as you normally would.

This sets the shoes up for maximum contact with the drum surface.

You can also put a shoe in a press and spread it or close it up slightly to adjust the contact pattern.

Hope this helps.

Shawn

Might want to change the front pads to a less grippy compound to help balance things.

I don't know what vehicle this is, but some drums have eliptical cams on the backing plate to make the shoes hit evenly inside the drum.

Dan

914Driver wrote: I don't know what vehicle this is, but some drums have eliptical cams on the backing plate to make the shoes hit evenly inside the drum. Dan

Those were back in the day when you had to manually adjust the brakes .

Sorry I was frustrated Nd didn't make a good original post. The car is a fiat 850, but the whole rear brake set up is a vw it's bug

icaneat50eggs wrote: Sorry I was frustrated Nd didn't make a good original post. The car is a fiat 850, but the whole rear brake set up is a vw it's bug

Not much help for this week but find some Porsche 944 rear disks, its a bolt on swap and should give you a better all around braking system.

that car could get by with Goldwing brakes on the front. like foxtrapper said, start by going to a less aggressive front pad.

Good idea on the pad, Ill have to look and try to figure out what's on there now