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Posted by: red914 Jan 10 2005, 10:47 PM

yep, here is another "shane and his rear brake caliper" threads.

sunday dino and i tried to pop the pistons on my rear calipers, all nice and removed from the car. well, well, well. one piston out of four came out. three did not budge. oh, correct that, one other one moved a teeny bit under c clamp pressure. 100psi got me one piston. tough to do a rebuild with my nice rebuild kits when the pistons are in the caliper.

it makes me wonder if my rear brakes ever worked at all... i have nothing to compare it too, and the 914 is light enough that i imagine fronts only would stop the car under normal conditions.

so, the struggle continues. there would be pictures, but dino's camera battery died as he was taking shots of his hellhole project.

Posted by: MattR Jan 10 2005, 10:56 PM

Did you soak it in WD40 or liquid wrench for a long time? That makes a big difference. I went to rebuild my 912 calipers and let it soak for about an hour, came back, and they came out with lots of air pressure.

You can also hook them up to the car and use the fluid and brake line pressure to push out the pistons.

Posted by: red914 Jan 10 2005, 11:00 PM

i had thought they were well soaked, but i was wrong. next step to to super soak then use the brake system to push 'em out. messy, but at this point i don't care. i do really wonder if they ever worked. what reasonable alternative do we have, without going 5 lug, to upgrade brakes (including rears) and have a balanced system? i haven't heard of any, but there should be a demand out there.

Posted by: boxstr Jan 10 2005, 11:10 PM

Shane I am sending a set of rear calipers from a 914-4 off to a new to me rebuilder.
I will let you know how they come out.
CCLINMIDASTOUCH

Posted by: red914 Jan 10 2005, 11:30 PM

i can't wait to hear how they turn out, Craig. i need to hear a happy ending.

btw, dino and i are trying to figure out how to come to camp this spring. we'll let you know. now if i can raise enough money for that little 912 you showed us the other day...

Posted by: dinomium Jan 11 2005, 12:22 AM

shane does have a SOOPER klean shop!


Attached image(s)

Posted by: drgchapman Jan 11 2005, 12:48 AM

Regarding rear calipers, I just spent the weekend replacing the 4 rubber brake lines with the braided steel , replacing pads and all 4 rotors and learning how to adjust the rear clearance. I ran into a bad caliper that would not adjust on the E-brake side. Guess what? Car wouldn't stop.........The adjuster screw turned, but nothing happened. Eventually.....I robbed the caliper off my a/xer to see if it would work.....Sunday, no way to find one .......and viola! we have brakes!!! I need to find a caliper rebuilder, or just buy a rebuilt one. BTW, the e-brake side adjuster cover comes in two hex sizes, some are 4mm and some are 6mm. My two '73's each have the different size. Best to find this out before trying to reach through (blindly) the trailing arm access hole with the wrong size allen wrench.

Maybe these are just noobie mistakes and I'm dumb.

Craig, got any more calipers to send to the rebuilder?

Gary

Posted by: skline Jan 11 2005, 12:54 AM

Has anyone tried this place? That is all they do is rebuild calipers.

http://www.goldlinebrakes.com/index.html

They are up in Washington, maybe Craig Laughlin knows about them or one of the members up there.

Posted by: dinomium Jan 11 2005, 12:57 AM

I have heard of them but that is all... I have 7 rears that could use a trip to camp! Brake calipers is what we are talking about... no other kind of "rears"
hehe

Posted by: skline Jan 11 2005, 12:58 AM

I would hope that is what we are talking about, I dont think Craig is like that.

Posted by: DJsRepS Jan 11 2005, 05:47 AM

I just had my drivers side rear calaper apart on Sunday. It was a rebuilt one that leaked out the adj bolt. It has a small Oring on it that I cant find anywhere. But I had trouble with the first piston, I pulled it out with vice grips thinking this should not be this hard on my replacment rebuilt calaper. Found that you need to use the adjuster screw to push the piston out. When I pulled mine it seperated the adjuster from the piston. If your piston is stuck use PB blaster spray then with the vice grips turn it to break it loose once loose use the adjuster bolt to push it out not air.

Posted by: red914 Jan 11 2005, 09:29 AM

the adjuster screw worked on most, but the outer adjuster screw on both rear calipers seemed to do nothing aside from give me practice turning a hex head wrench. after a while, i tired of the practice. but, based on recommendations here, i will try again.

oh, and goldline is supposedly where a southern california shop sends their rebuilds; was it otto's? i forget, but it was in a previous thread. they are right across the water in south seattle. i would hate to have to resort to that, but it is nice to know they are there.

time to go spray a bit more liquid wrench...

Posted by: boxstr Jan 11 2005, 09:35 AM

Guys mine are being sent out today I will let you know as soon as they get back, they are not going to Ottos.
CCLINBRAKEDANCE

Posted by: Dave_Darling Jan 11 2005, 10:05 AM

QUOTE (DJsRepS @ Jan 11 2005, 03:47 AM)

It was a rebuilt one that leaked out the adj bolt. It has a small Oring on it that I cant find anywhere.

Try calling GPR for that, or maybe Pelican.

--DD

Posted by: rhodyguy Jan 11 2005, 10:24 AM

South Side Brake and Clutch. d.s. in stock $95.59, iirc that includes new pads. if not in stock usually available same day. $75 core, take one with you for trade in.

kevin

Posted by: Eric_Shea Jan 11 2005, 10:58 AM

I rebuild rear calipers. I have three sets at the platers right now (2-sets of double bleeders and 1 set of single bleeders). They should be back this afternoon.

Shane, you say one "moved" and you also mentioned that you would use the brake system to get them out. If they "move" then the adjuster screws should screw them out. You "can not" remove the pistons with fluid without first disengaging the adjuster screws.

The pistons are spring loaded but still connected to the screws under normal operating conditions. This is one of the reasons the vening clearance is close. The other reason is the arm activates the inside piston and the travel is limited. Once the piston is set the fluid applies pressure and the spring loaded piston moved the rest of the way to clamp the caliper. If the adjuster screws turn, your pistons should move...

Turn "inside" adjuster screws clockwise. Turn "outside" adjuster screws counter clockwise. If you've turned them the wrong way they will not move. Instead they will probably break the small spring loose on the inner piston mechanism. If you're carefull you can reattach the spring. While turning the (4mm allen) screws "watch the piston". When it stops moving, turn the adjuster screw 1/2 turn further. At that point you should be able to grab the piston with some nylon jawed vise grips or (carefully) with a shop cloth wrapped around the piston. They only have about 1/8" remaining to go. Wiggle up and down with the pliers while pulling.

ATE does sell a rebuild kit for these calipers. It only includes the piston seals and dust boots. Pelican's kit comes complete with the o-rings needed to properly seal your caliper halves and the adjustment screws. If you need "major" surgery, meaning the parking brake arm is leaking, then you'll need to order a separate kit from the Ferrari crowd. They're an additional $50.00 There's an additional step needed to remove the cover and get the arm out and reseal it.

Let me know if you're interested in a pair...

Posted by: rhodyguy Jan 11 2005, 11:04 AM

what do you get for a set eric?

kevin

Posted by: Eric_Shea Jan 11 2005, 11:33 AM

It looks like they'll be roughly the same price as South Side. I'm not sure if they replate the calipers or not (probably not, but mine won't include the pads). Once all the parts are factored in they come out at $95.00 each or $190.00 for a pair plus core and shipping. If someone's hacked the outer adjustment screws then the margin is basically gone... and outer adjustment screws get hacked "often". Here's what you're paying for:

* Dissassemble Caliper
* Bead Blast Caliper
* Yellow Zinc Plating
* Hone Cylinders
* New Piston and Adjuster Rebuild Kits
* Reassemble Caliper

If the emergency brake arm needs rebuilding then I would charge an additional $100.00 each. I would rather not go that route. Not that it's difficult, it's a matter of economics. If you're going to drop $195.00 into a 4 caliper you can easily buy another core without the emergency brake arm issues for less than the $100.00 it would cost to rebuild that area.

Posted by: dinomium Jan 11 2005, 11:18 PM

OK, how bad does a piston has to be until it is time to just say good buy a used one?

Posted by: Eric_Shea Jan 11 2005, 11:21 PM

Talk to me... what happened and what's wrong with the piston?

Posted by: red914 Jan 11 2005, 11:33 PM

speaking for dino, perhaps out of place, the piston is slightly pitted and not wanting to come out of the cylinder. at all. so, if it is not mobile is it bad enough to be replaced?

hope that is what you would say dino. we never got to see any of your pistons on sunday, and only one of mine.

Posted by: Eric_Shea Jan 11 2005, 11:45 PM

Well Dino... weigh in if you get a chance but, If it won't come out you'll probably want to scrap the caliper.

Here's what I'm thinking though... with a "regular" caliper it can be difficult to get the piston out, struggling back and forth between the two. With a 914 "rear" it should be "much easier". Those adjustment screws should literally "force" the piston out. No if ands or buts about it. If you're up against stripping out the adjustment allen heads then you may need to soak some more and apply heat. All of the seals you would need will come in a PP kit.

You can hone the cylinder or even glass bead blast it (lightly) and you can use some 600 grit to polish the piston. The rubber seal that comes in the kit does all the... well... "sealing". If it's pitted too badly then replace.

Posted by: red914 Jan 12 2005, 09:04 AM

jumping in again...

on both of my rears (the subject of this thread), the outer adjustment screws turn and turn and produce nothing. nadda. the inner screws are what loosened the piston that popped. the other one gets a bit of movement. but the outer adjustments get no result.

prognosis, dr. brake?

Posted by: Eric_Shea Jan 12 2005, 10:39 AM

OK, I've got to ask a few questions to understand where you are with this. They might be rudementary but I need to know so, if I get too basic and offend don't go postal on me

1. Are you turning the adjuster itself (which is a 4mm allen screw in the center) or the 13mm lock nut? Simply loosen the 13mm and then turn the 4mm allen head center. A LOT of people turn the 13mm thinking it's the adjuster so I have to ask.

2. Are you turning them the right way? Outer screws need to be turned "counter clockwise" to force the piston out. Inner screws are turned clockwise. It sounds like yours were turned hard the "wrong" way initially and the adjuster screw is tightened into the inner piston mechanism. You may want to try a 4mm allen socket in reverse on an air wrench (high speed in reverse may break the bond).

That being said; the inner piston mechanism will turn or spin with the adjustment screw if it is fused in there. About the only way it can get fused in there is if they were tightened the wrong way, run dry, sat forever or had water in the system causing rust. The system is usually filled with brake fluid which provides excellent protection from rust and corrosion. I agree with your earlier assumption, those calipers probably weren't even working. This should help answer your other question about an upgrade: I believe once you get your stock brakes back to the way they should be you will be mighty impressed, especially with a good set of pads.

Options: If you are doing 1 and 2 properly and it is still spinning then I would say you "probably" have 1 option (maybe 2). Heat is where I would start. Here's how I would go about it:

1. Separate the caliper halves so you can work directly with the piston and adjuster in question. On early calipers you'll need a T27 Torx bit and an 11mm socket. On later calipers you'll need an 11mm socket. Remove the dust cover and clip and toss them.

2. Screw an additional 13mm nut over the end of the adjuster to protect it (let the nut overhang... does this make sense?)

3. Turn the assembly over and apply heat to the top of the piston. The adjustment screw is in the center of the piston. Use a MAP torch or regular propane but make sure you heat it up thoroughly. It will have to be "very" hot to get heat to the affected area.

4. On a hard surface tap the piston with the entire assembly resting in the 13mm nut you just installed. Don't whack it hard... just a bunch of light taps. It won't move. The taps are there to help break the bond.

5. Now, attempt to push the piston out using the 4mm wrench on the adjuster rotating counter clockwise.

The heat may also help break the bond the piston has with the cylinder wall.

There may be one other option to try before you get into the above proceedure. I have a grease gun that has a fitting that screws into the ATE fluid input. I use the grease with 120lbs. of air to remove pistons from standard calipers that are stuck. Again, your pistons will only "move" using this proceedure they will not come out (because the adjuster screws are still connected to them). If the pistons are bonded to the cylinder wall then this "may" help by breaking that bond. Grease is a fluid that won't compress. You can hook them up to your system as earlier mentioned if you don't have a grease gun but there's a bunch of variables like the proportioning valve etc. The proportioning valve "may" be your initial problem, not allowing enough movement (or any at all) to your rear pistons. If this is the case the "on car" pressure system may not work.

Whew... I'm going back to bed. Good luck and let me know what you come up with.

Posted by: 9146986 Jan 12 2005, 10:40 AM

The female part of the adjuster assembly, the part that's inside the piston, is turning. For the outboard adjuster, turning it clockwise should retract the piston in the bore. Use a clamp on the piston, and while under clamp pressure see if you can retract the piston with the adjuster screw. If you can get it to move, you can get it out. As suggested by someone else, you can try to turn the piston, but it's nearly impossible to do without chewing up the edge of the piston. You can turn the piston and gently pry up, but you pry too hard on the lip, you'll break it.

Posted by: boxstr Jan 12 2005, 10:41 AM

Hey how about making a phone call??
CCLINCANYOUHEARMEKNOW

Posted by: swood Jan 12 2005, 11:01 AM

Sorry, had to say it. Eric...why don't you help us all out since you're halfway through a "how to do it" thread and add pics for posterity's sake.

This is very useful information and I appreciate you taking the time for it. Especially since I'm next!

Posted by: drgchapman Jan 12 2005, 11:13 AM

Ok Eric, I'll bite. Where do I send my rear caliper for you to rebuild? As mentioned above, the inner adjuster (e-brake side) on this one just spins, no adjustment results.

I'll send once I know where.

Gary

Posted by: dinomium Jan 12 2005, 11:23 AM

I haven't retried mine, so they are still stuck. I was worried that if I took a pair of vise grips to the piston, I would chew them up badly.
Sorry for the high jack Shane SAN

Posted by: Eric_Shea Jan 12 2005, 02:42 PM

QUOTE

Sorry, had to say it. Eric...why don't you help us all out since you're halfway through a "how to do it" thread and add pics for posterity's sake.

Say "please"...

My hands have been too covered in brake fluid to be Mr. Photographer-Boy, besides f'n "Gint" will make fun of me if I post another "How-To" thread.

All of which means... let me get this batch of calipers back from the plater and I'll get started on the photos. I may start a separete thread so as not to hijack this one. I'll throw a link in here for those interested.

QUOTE

Ok Eric, I'll bite. Where do I send my rear caliper for you to rebuild?

Shea Suspension Services
10883 Pleasant Hill Drive
Sandy, UT 84092

Gary, it may not be rebuildable. How soon do you need it? If I can work them without a core we can see if it's possible. If not, we'll have to get another core to work with. Shane and Dino, this may be your problem as well.

Dino Don't try to pull it out with vise grips. You need to free up the adjuster screw. If that happens the piston will move. If you have broken the springs inside then you'll probably need new cores. I don't know of a supplier of these items.

Posted by: Gint Jan 12 2005, 05:55 PM

QUOTE (Eric_Shea Posted on Jan 12 2005 @ 01:42 PM)

QUOTE Sorry, had to say it. Eric...why don't you help us all out since you're halfway through a "how to do it" thread and add pics for posterity's sake. Say "please"... My hands have been too covered in brake fluid to be Mr. Photographer-Boy, besides f'n "Gint" will make fun of me if I post another "How-To" thread. dry.gif

NOW you're sensitive...

Bring 'em on babe!

Posted by: Eric_Shea Jan 12 2005, 07:08 PM

Posted by: red914 Jan 12 2005, 07:11 PM

wow, Eric, you have given me a bunch of stuff to work with. let me go down to the garage and monkey around a bit. can't let this inspiration die!

by the way, i did loosen the lock nut and turn the 4mm allen screw, but, as dino will confirm, i am just the guy to think the lock nut was the deal!

Posted by: red914 Jan 12 2005, 07:39 PM

harumph; still nuthin'. i'll keep at it. thanks for all the info and ideas.

Posted by: Eric_Shea Jan 12 2005, 11:32 PM

Teaser...


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Posted by: Eric_Shea Jan 13 2005, 12:34 AM

Just thought of one other thing Shane...

If you can get your 13mm lock nut off those outer adjusters, you can use the grease gun method to push the outer pistons out. This will still leave you with only "one" (inner piston) to go.

Buy a couple of cans of brake cleaner to get the grease off everything

Posted by: drgchapman Jan 13 2005, 12:46 AM

Thanks for the address, Eric. I'll send caliper next week, going to whistler this weekend for some R&R. Those calipers of yours look great!

Gary

Posted by: Eric_Shea Jan 13 2005, 12:53 AM

QUOTE

going to whistler this weekend for some R&R

Never heard of Whistler...

You need to visit http://www.alta.com. (note the zip codes)

Thanks, send the caliper when you can (we have 35 year record snow BTW...)

Posted by: drgchapman Jan 13 2005, 01:07 AM

Yeah, Utah rocks for skiing, best powder on earth! Been many times, love it there. Whistler, BC. Usually rated best ski area in North America. Unlike the Wasatch, they know how to party..... So we are going for the skiing and the night life....if I can last that long.

Love the look of those calipers!

Gary

Posted by: Eric_Shea Jan 13 2005, 08:57 AM

Got a point there... what's night life?

There's a pair with your name on them

Posted by: drgchapman Jan 13 2005, 09:52 AM

Thanks Eric. Get in touch this coming Tuesday when I return.

Did I mention those calipers look awesome?

Gary

Posted by: red914 Jan 13 2005, 10:06 AM

Eric, i just changed my background to that picture of those brake calipers. i can get the 13mm lock nuts off, no sweat. graese gun method it is. brake cleaner it is. been soaking them with liquid wrench a couple times a day, but to no avail. this weekend i will have victory. or maybe a beer in which to drown my sorrows. i greatly appreciate the input, help, encouragement, etc.

some of the locals here will attest to my novice status.

hey dino! do you have a grease gun? or should i go buy one?

Posted by: Root_Werks Jan 13 2005, 11:38 AM

QUOTE (drgchapman @ Jan 12 2005, 10:46 PM)

Thanks for the address, Eric. I'll send caliper next week, going to whistler this weekend for some R&R. Those calipers of yours look great! Gary

Gary, when are you planning on going up? My place is right on the way. let me know if you want to swing by for a break/beer/hot chocolate whatever. BS 914's for a few.

Posted by: drgchapman Jan 13 2005, 11:56 AM

Hey Dan, thanks for the thought. Leaving at noon today, have passengers, probably wouldn't be good idea, they would be terrifically bored. I have heard very nice things about you from the local Portland contingent. Very much looking forward to meeting you. Another time........

Are you sure that is your best side?

Gary

Posted by: Root_Werks Jan 13 2005, 11:59 AM

QUOTE (drgchapman @ Jan 13 2005, 09:56 AM)

Hey Dan, thanks for the thought. Leaving at noon today, have passengers, probably wouldn't be good idea, they would be terrifically bored. I have heard very nice things about you from the local Portland contingent. Very much looking forward to meeting you. Another time........ Are you sure that is your best side? Gary

Have a great trip, I love the drive up there!

Yeah, looking forward to meeting more locals (NW teeners) soon. When the days get a little warmer, I plan on putting something fun together for us NW people.

Actually I have been told the back of my head looks pretty good?

Posted by: Eric_Shea Jan 13 2005, 05:45 PM

Finally got the resource thread up... http://www.914world.com/bbs2/index.php?act=ST&f=4&t=23490

Shane... good luck

Posted by: DJsRepS Jan 14 2005, 04:16 AM

You guys know if the nut is off, the calaper is not threaded and the adjuster bolt can be pressed into the piston in an hydrolic press and just push out the piston and adjuster bolt together..... Bingo best idea!!! Or one could punch it out with hammer and punch. Then fix the threads on the adjuster.

Posted by: red914 Jan 14 2005, 09:01 AM

really? how 'bout gradual pressure from a big c-clamp. not to keen on pounding with a hammer.

Posted by: DJsRepS Jan 14 2005, 09:17 AM

Sure give it a try I do agree about the hammer. but I just had simular prob last weed when an factory rebilt calaper leaked on my car and it was the adj bolt has an Oring on it. It should not leak if the lock nut were loose. and it is a straight line bore for the hole of the adj bolt if you push it through the calaper housing it will push out the piston. You can at least turn the piston a little I hope it is not frozen solid. PB blaster is the best. If it wont push out Frozen solid try lightly tapping on the piston just to jar it loose.

Posted by: DJsRepS Jan 14 2005, 09:18 AM

Opps typo should have read week not weed!

Posted by: Eric_Shea Jan 25 2005, 07:12 PM

Status? Shane?

Posted by: red914 Jan 25 2005, 10:32 PM

Hey Eric! thanks for the interest. after awhile, i figure everyone had grown weary of my brake blues . but since you asked, here it is in a nutshell:

last saturday at Big Dan's Big Parts Party i got his rear calipers (for cheep; thanx again, Dan!) these got rebuilt on sunday. they came apart easily, went together easily, and the missing inside adjuster insert was easily replaced from my set! you, and others, led me to much needed understanding of how these contraptions work.

this coming weekend comes the remounting, brake pads replacing, fluid replacing, bleed-a-thon! then, a drive!!!! all is well, so far.

like i said, though, i figure everyone was tired of hearing about it. thanks again for all the help. wish i could afford to have you make 'em work and be pretty, but this is a budget project. i did have your pic of the shiny calipers as my background until these got rebuilt. inspiration!