Rehauling e-body HD drum brakes

[kawahonda]

Does anyone know of any good Youtube or visual guides (aside from what I will look for in the FSM) about rebuilding drum brakes?

When I had first bought the car, the first thing I did was buy a complete brake replacements from Rock Auto. Probably easily $500-700 worth of stuff. I've been having too much fun with the car, and have put it off until today.

Today on the way home (only a mile away is where I work) I found that I did not have any hydraulic pressure anymore. Pushing the brakes all the way down turned on the parking brake light, which was interesting. The car was able to stop OK still, but it is not what I consider safe anymore.

I have rebuilt drum brakes in motorcycles all the damned time. You put the shoes in, connect the spring, and your done. Drum brakes are cars seem far more complex, so I'll appreciate any reading material you guys have.

My plan of attack is to do one wheel at a time, then crawl under the car and replace ALL lines/hoses/fittings/connections. Dot 3 or Dot 4?

Probably need some specific brake tools? I do have a bleeder tool, but I'm sure there's drum-specific tools?

[JS29]

@Shane Kelley has a nice article on this vary topic, I do not remember were. 

[JS29]

It's at the top of this thread.

[73_Cuda_4_Me]

Sounds like you got a pin hole in one line, or one of your piston seals popped in the drum brake cylinder...

You will at a minimum need something like this from HF...

https://www.harborfreight.com/drum-brake-spring-pliers-kit-3-pc-63640.html

You will have to remove the rubber oblong plug in the backing plate at the bottom, and loosen the star adjuster so the drum can slide off the drum shoes. There will be a ridge from wear in the drum, so the shoes need to be loosened to let the drum ridge clear the edge of the shoes.

Factory Service Manual will  have a good procedure written up in it for doing the shoe replacement.

Look for wet spots along brake line to find pin holes... if there is just oil in one of the drums, then the brake cylinder in that drum will need to be rebuilt or replaced.

There is a primary shoe (shorter brake pad) and a secondary shoe... primary goes toward the front of the vehicle...

Mind the adjuster cable routing inside the drum, too... take pics for reference if you aren't familiar with it...

[kawahonda]

Got tools at HF.

Started on Passenger side front. Going to drain fluid tomorrow and then
Begin studying how to disassemble the drum unit.

Rear pocket of MC didn't have a whole lot of fluid.

[kawahonda]

I assume MC unfastened from the cockpit? 4 mounting bolts....what else?

[dodj]

I assume MC unfastened from the cockpit? 4 mounting bolts....what else?

Nothing else, it should come off now, but likely need a little 'tap' to loosen it up?

That is the nastiest brake fluid I have ever seen. 

[Katfish]

Good time to switch over to silicon brake fluid, DOT 5

[kawahonda]

Dot 5 it will be....

I brought all this stuff down from the attic....it's been sitting up there for 1.5 years.

Why am I doing this just now?

I've always been very happy with the HD Drum brake performance...it's going to be nice to see what a brand new set feels like.

I don't think I am replacing the hardlines...they look pretty darn good.

[JS29]

As nasty as that fluid looks, I would change everything! 

[kawahonda]

I guess I still don't understand. It's more than those 4 nuts.

[kawahonda]

Is this like a ball joint that just pops off with enough force?

[jamesroney]

I assume MC unfastened from the cockpit? 4 mounting bolts....what else?

You have to disconnect the pivot bolt that attaches to the pedal.  It connects the pedal to the master cylinder pushrod.  The pushrod, valve, and retainer are all serviced as part of the master cylinder.

When you remove and install the master cylinder, it should have the pushrod attached to it...otherwise the fluid will all leak out, and you can't install the pushrod retainer. 

[kawahonda]

Guess I need a pushrod, boot, and retainer?

Still not sure why these should be serviced if they are in great condition. They are not internal parts?

My raybestos MC just comes with the inner workings, nothing attached to it, just the outer piston.

I still need to attach the pushrod to it, either a new one or my own. Is this just a press fit thing?

[jamesroney]

It's there, I can see them.  PM sent...