WTF Caddy rear brakes?

[wolf_walker]

The drums are new, 199.75mm ID, no lip so I pretty well trust my measurement.  201.5mm is worn out so they should be just peechy.
There might be half a mm diff in the thickness of the two sets of shoes I have.  I'm going to order another set of Febi's I've used before
I guess, and maybe another set of Gemo brake cables if I can find any.  Running out of ideas.

[wolf_walker]

Here's another puzzle piece. 

I replaced the wheel cylinders, shoes, drums, bearings, cables, and it still isn't right.

I have a photo I took of the previous parts, and the adjuster wedge was all the way down,
but there was plenty of brake shoe left.  PO says He can't remember exactly but last time
he did rear brakes, and he's plenty experienced, he couldn't get them to adjust right either
regarding the e-brake, and the pedal has always been low.

So it's completely possible that replacing all this stuff with new, did not fix the problem, whatever it is.

So what the hell could it be?  I'm out of stuff to replace short of the damn brake backing plate, and the lower
pivot point does not look worn.  The crossarm between the shoes on the top shows some wear where the
e-brake arm contacts and the adjusting wedge moves, but it isn't excessive, and plus I shimmed both sides
and it might have helped a little but I think it was addressing a symptom not a problem.

So weird.

[burn_your_money]

I don't know if they are different but maybe you have a 180mm crossarm on there

[wolf_walker]

They are different, and it's obvious, it's a 200mm piece.  Good guess though.


Another maybe-puzzle piece.
My brake pedal at rest height is way, way lower than the clutch. 
Higher than the throttle, but still way lower.
The pushrod is non-adjustable under the dash.
It has what feels like 5-7mm of free play which is about right I believe.
But it's just low, I don't see anything bent, and no way to adjust either the
clutch down or the brake up.

Curious no?

[CRSMP5]

someone will one day make thicker/wider wedges... LOL...

adjustment on a 81-84 westy is between master and brake booster i think... the rod adjusts there.. well ball on the end of rod..

[CRSMP5]

also.... quick is it rer brake test...

using some vicegrips... pinch off.. not crush... the rear rubber brake lines.. if pedel goes up its in rear brakes.. if still low.. not the issue..

[wolf_walker]

There is an adjustment there, I can't find a spec for the later A1 for the length of that rod, logic says it ought to at rest almost touch the master cylinder inner piston, but not quite.
I plan to measure and futz with it when my, leaking, new master cylinder is off again.  I did notice it was adjusted out a good ways when I glanced at it before.
This isn't going to effect the brake pedal position at rest I don't think but it might have some benefit.

And roger that on the rear brake test, I have plugs for the master cylinder for checking that I usually use.  I don't doubt that's where the long pedal travel is too much, I shimmed up one drum at the e-brake contact point on the cross bar and on the adjuster side out of curiosity and it did improve the pedal.  It just don't explain why there is so much room between the damn drum and the shoes...

[wolf_walker]

Got some Febi shoes in and some FTE wheel cylinders, going to put them on this evening hopefully.
Interesting the wheel cylinders are aluminum, haven't seen that before but they seem to list all the right specs for them.
They also have one mounting bolt, and have a slip of paper mentioning that it's ok lol.
The shoes are noticeably better made, and they all match like they should, and the linings aren't bonded on crooked like the other two pair...

[burn_your_money]

any updates?

[wolf_walker]

Not yet but hopefully tomorrow.

I got the german wheel cylinders and german shoes installed and un-bent the cable guide on my hand brake lever and it's waiting.

I got in a nice german ATE master cylinder for $180 shipped overnight from the east coast, it's a work of art compared to the reman garbage
I've had two of and looked at several locally from the McParts stores. 

My booster seems to check out, I had another fellow kind enough to give me a measurement on the brake pedal rod on his factory 82 booster
and mine seems close near as I can measure with it in the car.  I can't account for the lower pedal position than I think it ought to be other than maybe
stacked tolerances and general sloppy 80's american built VW-ness.  One day I'll pull the pedal cluster and have my wife weld an extension on the damn
pedal pushrod I guess to get it up where it ought to be.  Or swap it all to proper full ATE stuff.

Hopefully tomorrow I'll put the power bleeder on it and see what happens, low pedal or high e-brake or not, I plan to drive it long as it feels safe.

[wolf_walker]

Oh, and after a lot of measuring and poking and pondering, I lengthened the master cylinder side push-rod about 2mm.  There is still plenty of feel-able free play at the pedal before it contacts the master cylinder, my hope it is gained me a little more useable pedal since it seems to be chronically low.  I really wish they'd published a spec on the damn thing since it's clearly adjustable for a reason.  I believe it could be tighter than it is but I erred on the side of caution.

[wolf_walker]

Test drive after work, but it's back together.

The rear brakes STILL dropped the adjusting wedge darn near half way right off the bat.
The parking brake STILL required ALL the adjustment available at the handle to function.
In that order.

I shimmed the cable sheath 22mm's at the backing plate and that gave me a good adjustment range.

I power bled the brakes twice, pedal is still low but firm, just like it's been for ages.

As long as it stops reliably I'm going to leave it be for now.  Something is fundamentally fubar and I don't know what it is.
I'm remembering why I love old Mercedes.  

[wolf_walker]

Last update, I hope.  Test drove and didn't die.
Pedal came up a little after some use, it's still not a Mercedes but hey..

I still don't know the why of the oddness, but it's there, and I'm going to run out of adjustment range on the auto-adjuster
for the rear shoes long before it should, but it's a ways off.

In a few weeks I'll put GTI pads and rotors up front and hopefully forget about the brakes for awhile.

My new balljoints allowed me to feel the little bit of inner tierod play I had much more dramatically, so up goes the front
tomorrow for all that fun.  Then finding an alignment shop. 

[745 turbogreasel]

You always feel the next weak link in the frontend