Need a pic of e brake shoes etc.

[ganun]

Could someone show how the e brake works.....I need the arragement of the cable clip spring and other clip.
I think I should assemble the whole e brake and cable before pressing in the hub, I am currently in the middle of a wheel bearing replacement and the e brake was not functional on that side so I don't know how it should be.
Thanks

[MConn]

Here's a pic -



The cable is retained with the castle nut, and when you pull up on the parking brake lever, the cable compresses the spring, causing the metal tabs (levers?) to extend out, pushing the brake shoes against the inside of the rotor hub. (I think)

Mike

[ganun]

Thanks, I found another set of levers(tabs) on the floor that must have dropped when I pulled the cable thru.
So is it one set of tabs or two, the second mirror of the first?

[MConn]

I believe that there is another set of tabs, mirrored that catch the pins on the back-side of the brake shoes, and the spring is sandwiched between the 2 tab sets. I remember that it was a bugger to get the castle nut in place without loosening up the adjusting nuts on the cable assembly behind the trailing arm. And don't forget the spacer tube on the cable assembly (like me).
Mike

[MConn]

[JohanG]

really nice drawing ! wish i had that when i took mine apart



somehow when the cable got "pulled" my brake shoes didn't get pushed apart far enough.. after a weekend of putting it on.. adjusting.. off.. on .. adjusting.. off .. on ( you get the picture ).. a week of misery and... an insight what if its not an "adjusting thing..



is it worn ?? does it measure right ?

old brakeshoes .. and new.. hmmm

GRINDER..




it works again.. ( note to one self.. get data as of how long the "tabs" should be and perhaps buy new ones )

[Porboynz]

Oh my gosh JohanG, something is not right with your e brake assembly. For starters the retaining spring looks like its attached to the wrong holes in the brake shoes, or you have the wrong brake shoes? That spring should be a near straight pull, not curled around the pins the butterfly expander operates against. Do you have 2 of the butterfly expanders fitted? One on the outside and 1 on the inside with the coil spring between them to keep them expanded against the cable end nut/washer and the metal tube pressing on the inner one? (the metal tube that is not shown in the MConn diagram) I have a few spare butterfly expanders kicking around as spares, I'll measure one tomorrow but usually they fall apart when they are worn out. That brake shoe that's been introduced to a grinder, please tell me that's not in your 911? If you had to grind clearance its definitely the wrong part.

[JohanG]

Porboynz: old brakeshoes matches the new ones purchased, so i guess its the right brake shoes.. and i'm not worried about the spring ( it just drags the shoes towards each other and center, and from what i can see works )

both butterfly expanders are fitted, including coil spring and metal tube ( which is missing in the earlier very good drawing ).

since "nothing happens" when i pull the cable, see in my picture, the outside ( and inside ) butterfly has NO slack, it doesnt push the brake shoes outwards at all ( well a couple of mm but it is not enough ),

so grinding the edge of the shoe makes the brake shoes come closer to one another so my ( what i guess ) worn butterfly expanders may actually be able to push the brake shoes apart at all , so the grinding is not for clearance rather the other way around..

However i'm not saying its the right way to approach any problem.. ( grinding away material ) i just know that now i have working e-brake

but i would be glad if someone have the measurements of the butterflys and post it so i know if my guess i correct ( if not its a winter project to sort it )

[ganun]

Thanks for the diagrams, I put it together and noticed the inner "butterfly" is slightly thicker in the middle square piece than the outer, maybe just imagining that .
Very fiddly to assemble onto the hub!
Johan, that spring is is not correct, it should be straight, see my pic.

BUT, on mine the spring on the adjuster side rubs on the adjuster......is this correct?
See photo

[MConn]

Originally Posted by ganun

...on mine the spring on the adjuster side rubs on the adjuster......is this correct?

That matches my pictures, I think the spring is used to keep the adjuster from turning on it's own. This is typical with the drum adjusters I have seen on other cars.

Mike

[ganun]

Thanks McConn, and all the others, test drive showed I can lock both wheels now, success.

[bodmin]

Pictures from my rebuild album which may assist.

[Porboynz]

Originally Posted by ganun

Thanks McConn, and all the others, test drive showed I can lock both wheels now, success.

Nice work, the E brake is useful for hill starts and parking on hills etc, just for interest I tried using it as a true emergency brake once and you would need a lot of room to stop you from 50mph+

[Porboynz]

Originally Posted by JohanG

Porboynz: old brakeshoes matches the new ones purchased, so i guess its the right brake shoes.. and i'm not worried about the spring ( it just drags the shoes towards each other and center, and from what i can see works )

both butterfly expanders are fitted, including coil spring and metal tube ( which is missing in the earlier very good drawing ).

since "nothing happens" when i pull the cable, see in my picture, the outside ( and inside ) butterfly has NO slack, it doesnt push the brake shoes outwards at all ( well a couple of mm but it is not enough ),

so grinding the edge of the shoe makes the brake shoes come closer to one another so my ( what i guess ) worn butterfly expanders may actually be able to push the brake shoes apart at all , so the grinding is not for clearance rather the other way around..

However i'm not saying its the right way to approach any problem.. ( grinding away material ) i just know that now i have working e-brake

but i would be glad if someone have the measurements of the butterflys and post it so i know if my guess i correct ( if not its a winter project to sort it )

This is very odd, because by grinding away the ends of the brake shoes you are moving the shoes further away from the drum, so the butterfly expanders need to move them that much more if you see what I mean. Something's still wrong, I'll find the measurements of a good expander and post them for you.

[Porboynz]

Originally Posted by Porboynz

This is very odd, because by grinding away the ends of the brake shoes you are moving the shoes further away from the drum, so the butterfly expanders need to move them that much more if you see what I mean. Something's still wrong, I'll find the measurements of a good expander and post them for you.

OK, I made a trip out to the garage and found the box of brake parts and here is what I measured. First photo, the expander is laying flat on the table and I compressed it so its as short as it can be laying flat, it measures 61mm from the lowest point of the curved half circle recess at each end to the other.



Photo 2, still laying flat with an older rusty expander for comparison, both are the same at 70mm end to end.




Last photo, I know you guys still use inches so here is the other side of the ruler, looks like 2 and 3/4 inches end to end, laying flat on the table, with the ends pushed towards the centre to take up any movement.



I flipped the expanders over in this photo to show the inner side that locates the coil expander spring. Hope this helps, your photo shows your expander to be about 2 and 1/16th inch long (maybe 52mm) where the ones I have are much longer, so you have different expanders. Maybe they are the wrong type, hence your problems. Mine fit a 1972 and probably any 911 with M type brakes on the rear.

[ganun]

Porboznz, it looks like the top one is taller and the curve is more pronounced, or is that a result of the pic angle.....
Sorry but I have nothing to offer Johan other than the shoes must be for a different application.

BTW I did notice a "clack" sound when pulling the e brake while moving....must be the sound of the shoe hitting the big stop as the expanders lift them off the stop. Maybe its got too much clearance off the stop cause I tightend the cable a bit too much.

[GH85Carrera]

Originally Posted by Porboynz

Nice work, the E brake is useful for hill starts and parking on hills etc, just for interest I tried using it as a true emergency brake once and you would need a lot of room to stop you from 50mph+

It is not really an emergency brake, it is a parking brake. That is why you have a dual master cylinder. It is very unlikely both circuits will fail.

With just the rear wheels stopping you, you are right it will take a LONG time to stop and if you lock the rear wheels you are going for a scary ride.

[ganun]

You are right GH,
I use it while moving occasionally not to stop the car but rather to keep the brake drum clean

[JohanG]

my Pictures are from a car from 1979

Porboynz:
my expander at 51 mm compared to your expander with 61 mm
ehrmmm yep theres some difference there..
worn 5mm on each side 10mm in total ? seems strange.... rather like you say, different breed...


well... winterproject im just fine with getting it through Swedish TUV, and I'll use it for parking ( not emergency braking )

[Porboynz]

Originally Posted by JohanG

my Pictures are from a car from 1979

Porboynz:
my expander at 51 mm compared to your expander with 61 mm
ehrmmm yep theres some difference there..
worn 5mm on each side 10mm in total ? seems strange.... rather like you say, different breed...


well... winterproject im just fine with getting it through Swedish TUV, and I'll use it for parking ( not emergency braking )

Sorry I did not notice you were posting from Sweden and there I was mucking about with inches, we went metric about 30 years ago and its a struggle to remember 1/16th and 1/8th of an inch measure when mm are so much easier.