Rehauling e-body HD drum brakes

[MoparLeo]

STOP, STOP, STOP, !!! This not the time to learn about the most important safety system on your car by just looking at pictures and people assuming your knowledge level. Get a Service manual and read the brake section completely over and over until you understand everything. Then you can ask specific questions if you need to and refer to the service manual for more detailed explanations. No body is born knowing anything, we all have to learn but you know the saying that " you have to learn to walk before you run"  Here is a link to download one for free. Make sure to use fluids from factory sealed containers to assure no contamination.
http://www.mymopar.com/index.php?pid=109

[kawahonda]

My predicament.

OK, what's already install may just be the front piston assembly, but I think it's both front and rear. 

FSM does not do a good job explaining the rod connection. In fact, it cleverly deleted it in all images. This is why I think it seems to be external and detach/attachable. 

Notice what these parts are sitting on, mopar Leo.

[jamesroney]

My predicament.

OK, what's already install may just be the front piston assembly, but I think it's both front and rear. 

FSM does not do a good job explaining the rod connection. In fact, it cleverly deleted it in all images. This is why I think it seems to be external and detach/attachable. 

Notice what these parts are sitting on, mopar Leo.

You are correct.  The master cylinder on the LEFT is for an e-body. (and contains both front and rear pistons.)
The piston and rod on the right are from a different Mopar.  (I'm still trying to figure out what...)
You are going to have another problem when you go to bolt on the master cylinder.  A non-power brake e-body pedal support has nut plates welded on, and has bolts attaching from the engine compartment side.  Power booster pedal supports have studs with nuts accessed from the passenger compartment.

Unless the A66 Challenger has something different...somebody has done something in the past to make it all work.

[jamesroney]

To answer your question...if in fact you have a 60's full size master cylinder, then yes...there is a ball joint with a retaining clip that holds the pushrod to the piston.

Take a look at these pics and see if it matches what you removed...

[71vert340]

  It almost looks like the rear piston assy on the end of the rod came out because there was no snap ring to hold it in. See the FSM drawing I'm attaching. The rod should just press in to the back of the master cylinder. A mis-match of parts?
Terry

[Katfish]

That looks like exactly what happened.
Need to separate those 2 pieces, getting the push rod out can be a pain.
Throw some vice grips on the lower section and beat it off.

[kawahonda]

Here's a cross section view

I assume this "tip" (with the rubber) just rides in the round divot in the master cylinder?

Or do I have a miss match somewhere?

Here's the junk MC that I removed. Clearly a replaced during the past.

[kawahonda]

Other good news is I got one done. Won’t touch lines until the very end.

Before/after.

Picture of old shoes as well.

The green and blue spring were not replaced, since there was no replacements in the rebuilt kit. I also did not replace the show mounting studs because the ones in the kit were all shorter than the OEM ones. Yes, the larger shoe is on the rear. Yes, I greased the contact points in the rear behind the shoes.

[71vert340]

 I've just lubed the ball end of the shaft and it inserts into the back of the master cylinder . If someone else does it a better way, I'm sure they will share their method.
Terry

[kawahonda]

I need to know how far to take this job.

1) Assume that I should replace the original drum hub?.....if so, I will get the hub soaking in PBW overnight and start a beat-athon. I will have some wheel bearing grease questions later. Or, just clean and reuse and save the new drum hubs for next time?

2) Should I replace the hardlines? That will turn this job big, because that means all the valves along the way as well. My first thought was to blast it out with brake parts cleaner until it comes out clear, then assess...

[71vert340]

 Are the original drums in good shape and still more than minimum drum thickness and less than maximum inside diameter specifications? This determines if I replace mine.
I always replace the bearings/races in the hub if I see even the smallest amount of rust pits, grooves, etc.
Always replace the grease seals.
I flush out my hard lines with brake cleaner and blow compressed air through them and then evaluate if they need to be replaced. If rust comes out, replace.
Proportioning valve needs to be cleaned and checked for leaking, operation, etc. If leaking, rusty or corroded, replace. I told my son while building his 71 Challenger and my grandson who is helping me on my 74 Charger that it doesn't do any good to be able to go if you can't stop.
Terry

[kawahonda]

I'm actually pretty happy with the lines. See pic.

Not sure of min thickness spec, cannot find it, but the new drums are thicker and consistent.

Slight grooves in old drums.

I say keep hard lines, and replace drums hubs. 

[MoparLeo]

The hubs are used over. Don't beat on it, you need to press the studs out and have new studs installed by the machine shop that presses the old studs out. The new studs are swaged after drums are placed back on the hubs. That is what holds the drums to the hubs. Your return springs need to have the ends that go over the top backing plate stud bent almost closed. Look at your old picture and look to see how the ends of the springs are squeezed into a more closed condition. All metal contact points such as the backing plate pads where the shoes rub against the ... you know it is ridiculous to have to explain every little thing about how it should be done. Get someone to help you that has brake repair experience, We cannot be there to make sure that you have the right parts and do the little things that need to be done. You can't just assume that it was done properly the last time someone did your brakes and then copy their mistakes.Like the proper master cylinder. Someone familiar with the car would have known immediately that the wrong part was there. Saving a lot of time, questions and possibly putting a wrong/dangerous part on the car. Don't take it personally, I don't want you to get hurt.

[71vert340]

 I should have stated drum diameter or minimum thickness. I've seen drums marked both ways. See photo. If the drums are not out to the maximum diameter, than they have good thickness unless there are deep grooves that would not machine out when turned.  Use new drums if grooved.
Terry

[71vert340]

 Another drum. And I've seen drums with no markings.
Terry