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Eric_Shea
In an earlier thread I was asked to write a “How-To” thread on the rear caliper rebuild. I had to get some pictures together before this made sense.

I’m starting this thinking you’ve already gotten them off the car and you understand how to reinstall them and bleed your brakes. This is all about the caliper rebuild. This is also about a “top-end” caliper rebuild. If your caliper is leaking through the handbrake lever I would consider getting a new core at least. Why? Rebuild kits are around $22.00. Handbrake rebuild kits are around $50.00. Now you’re in it for close to $80.00 with shipping etc. A rebuildable core should go for $20-$40 bucks… as these get scarce you may want to reconsider but currently they’re not too scarce.

This job is not fun and it’s not all that easy. It’s not too tough either, it just requires some mechanical ability, patience, special tools and some “tricks of the trade”. Yes, I rebuild these so I’m either loosing customers or gaining customers by writing this (I’m obviously not too concerned). Follow the thread. If it’s something you want to tackle then dive in. If not, you know where to go.

Here are some of the tools you’ll need:

 Dental Pick
 T27 Torx Driver (early single bleeder style)
 Torque Wrench
 4mm Hex key
 Small and Large Locking Pliers
 Brake Grease
 Brake Cleaner
 Large Screwdriver
 Small Wire Brush
 13mm Socket
 11mm Deep Well Socket (to press the spring and cover into the inner caliper half)
 11mm Socket
 MAP Torch
 Air Wrench
 Pistol Grip Clamp
 Brake Caliper Hone
 Hand Drill
 Two Rear Caliper Rebuild Kits from Your Favorite Vendor (they must include all seals)
 7mm Wrench (for the bleeder valve. I prefer to use a small pair if locking pliers though…)

Here’s the “How-To”

1. Drain it. You’ll want to get all the fluid out of these before you dig into the task at hand. As mentioned above, take a pair of locking pliers and snug them down on the bleeders. Most are stuck and this is the only way to go. The 7mm wrench will rarely do the trick. Once you get them off, try to blow some air through them.

2. I like to mount these in a vise before I start the dismantling process. Next I start with the caliper half bolts. These are 11mm bolts on the later style (dual bleeder) or T27 Torx bolts on the early calipers (single bleeder). The early calipers have 11mm nuts on them. These will seem impossible to remove. Here’s where the MAP torch comes into play. Don’t worry too much about heating these puppies up. First of all, brakes get hot. Second, you have new seals in your rebuild kits. You just don’t want to heat up the parking brake area because as discussed earlier, that’s another $50.00 in parts and another rebuild. Heat the bolts and use your air wrench to hammer these off. Split the caliper and remove the inner seals. While you’re at it, remove the dust boots and clamps using the dental pick.
Eric_Shea
3. Turn out the pistons. The heat you used on the caliper half bolts may have helped you on the piston side. Many have complained about stuck pistons that have the internals “spinning” (you’ll see what that means when you get one out). I’ve found “heat” to be a “major” factor in getting out these types of pistons. Keep your MAP torch handy. I mention “Inner” and “Outer” caliper halves; The inner halves have the parking brake arm attached. For the “Inner” piston you need to spin the adjuster “CLOCKWISE”. “Outer” pistons turn COUNTER CLOCKWISE. For the outer adjuster you’ll need to loosen the 13mm lock nut and spin the adjuster with a 4mm hex wrench. For the inner adjuster you’ll need to use the 4mm hex wrench to remove the adjuster cover. Many times this is stuck and the 4mm slot is stripped (has something to do with thread surface area and wrech surface area). If this is the case you’ll need to slot the cover and pop it with a large screwdriver or chisel (see picture) Turning out the pistons is the part that I feel is “easier” than any other caliper rebuild. If your calipers are in decent shape the pistons should simply spin right out to the edge. Once you get the adjuster screws turned out to their limit (you’ll feel it and the piston will stop moving), you’ll need to pull the piston out the rest of the way. Do this by placing a shop rag over the piston and use a large pair of locking pliers to grab the top edge. Don’t dig into it and destroy the lip. Just snug. Now “rock” the piston back and forth while pulling. It only has about 1/8th of an inch to go.

Here's a picture of the "inner" adjuster cover and the modification discussed above that is "usually" needed to get them off
Eric_Shea
Turning out the piston... (and yes, these will clean up to like new condition)
Eric_Shea
Gently rock back and forth.
Eric_Shea
4. Remove the adjusters. The outer adjuster will pop out after you remove the “clip” that is on the shaft just above the 13mm nut and the nut itself. Once the nut is off the adjuster simply pushes into the piston cavity. The inner adjuster is a bit tricky. It is set in with a hat, a spring and a clip that holds all that in there. Are you sure you want to do this? It’s “really” fun putting it back! IPB Image Use the dental pick again and pull the clip inward and upward. I like to cover the piston cavity with a shop rag so the clip doesn’t go flying. Once the clip is out of it’s groove the adjuster, hat and spring should pull out. It comes out hard but it comes out. There should be a little “sausage” attached to the bottom of it with grease. The “sausage” may stay in the lever assembly but most come out with the adjuster. The “sausage” (as I like to call it) goes into a recess in the rod and pushes against the adjuster when you pull your handbrake lever. Next time you pull up on the handbrake, thank the “sausage”. Pull the adjuster gear out when you remove the 4mm hex key.
Eric_Shea
Inner...
Eric_Shea
Inner adjuster pulled out... see the sausage? IPB Image
Eric_Shea
5. Use the ever so handy dental pick to remove the piston seals.
Eric_Shea
6. Optional. If you’re going to plate or paint your calipers (and why wouldn’t you while they’re apart) then you’ll probably want to take the handbrake spring off. To do this you’ll need to remove yet another clip (ATE seems to love clips), slide off the washer and then use the small locking pliers and grab the spring just past the bend and pull up. The tension is not that great so don’t worry about it flying across the garage. Next remove the spring rest from the shaft.
Eric_Shea
7. You Decide. You now have a totally stripped pair of caliper halves (or two pair). This is where I loosely bolt them back together and bead blast them. I then take them off to a local plater and have them “yellow” zinc plated to replicate the factory finish. Clear zinc will net you a silver caliper. If you decide to paint at this point, use a very high temperature paint. Rotor temperatures can exceed 1400. If you decide not to plate or paint this is where the wire brush and brake cleaner comes in handy. Spray and clean. Spray and clean. Spray and clean.

8. Ready to reassemble?
Aaron Cox
sissy boy - uses latex gloves.... IPB Image IPB Image
drgchapman
Looks like I won't try this at home, calipers shipped out yesterday. Do me gud! IPB Image

Gary
Eric_Shea
9. Install the piston seals from your kit. They don’t seem like they’ll fit but keep pressing them around and use that handy dental pick to position them. Soon enough they’ll drop right in the groove. I lube them up with brake fluid before I install them (as I do with all the seals).

10. Install the adjusters. Clean them up with the brake cleaner and the wire brush first. Remove the old seals and install the new seals from your rebuild kit. The outer adjuster simply pushes right in (use brake fluid as a lube on the seal). Install the 13mm nut and then reinstall the clip. The inner adjuster is a bit more complicated (remember… you wanted to do this). Use the brake caliper grease and load up the hole at the base of the adjuster where the famous “sausage” goes. Insert the sausage and spread some of the extra grease on the gear. Push the adjuster into position and make sure it drops fully into place. Place the spring over the adjuster and follow it up with the hat. Place the clip over the hat and your ready for the real fun stuff. Use the 11mm deep well socket and use the “Pistol Grip Clamp” to press the assembly in to place. Dental pick time again; use the pick to press the clip back into the groove. Once you know for sure that it’s snapped into place, release the clamp. Install the adjuster gear and use some new adjuster covers for the inner halves.
Eric_Shea
Inner Adjuster Rig...
Eric_Shea
11. Install the pistons. I tape them off and bead blast the tops to bare metal. They tend to be a bit rusty. While they’re still tapped I put a coat of high-temp gray on them to replicate the factory finish. Once they’re dry you can remove the tape and use 600 grit wet-or-dry to polish the edges. Now you’ve got some nice pistons and they’re ready to “pull” into the cylinders. Here comes a little trick; install the dust boot now. Next, use the caliper grease and put a light film on the piston and the cylinder wall. The adjusters go in the reverse direction to install the pistons (ya think?) Outer adjusters turn CLOCKWISE, inner go COUNTER CLOCKWISE. Turn the pistons in all the way but don’t crank them down too far. You can bust the springs on the inner piston assemblies (you don’t want to do that). When they stop moving, stop turning. Install the dust boot clamps. Tip: Dust boot clamps are now coming untrimmed -or- a bit too large. Take a pair of stout wire cutters and trim them down to the appropriate size.
swood
QUOTE (Eric_Shea @ Jan 25 2005, 09:07 PM)
In an earlier thread I was asked to write a “How-To” thread on the rear caliper rebuild.

Ok, Eric. Here's where I say "THANK YOU!" IPB Image IPB Image
Eric_Shea
Dust Boot Trick...
Eric_Shea
Pulling in...
Eric_Shea
More...
Eric_Shea
12. Reassemble the caliper halves. Use the two seals in the rebuild kit. Lubricate them with brake fluid. Position the half with the détentes horizontally in a vise, put the seals in and drop the other half on top. Install the bolts and torque to 7lbs. starting with the two inner bolts and then the two outer bolts. Next, go back and re-torque to 17lbs. using the same pattern.
Eric_Shea
13. Install the spring rest on the shaft. Position the lever toward the outer caliper half and install the appropriate spring (the springs are left and right). If you get the wrong spring your handbrake will be on all the time (in theory). Use the small locking pliers again to grab the spring and position it in the groove. Use a screwdriver to push it the rest of the way on to the shaft. Install the washer and reinstall the clip.

Whew… I think we’re done. Install. Bleed. Adjust etc.

Hope that helps!
SpecialK
Fantastic "how-to" Eric!!

And timely.....just disassembled my r/h rear caliper.

About how much does it cost to cad plate the calipers? You prices are regional of course, just curious about a ballpark figure..........waaaay pretty when they're done!!
Eric_Shea
QUOTE
sissy boy - uses latex gloves....


Keeps the grease off my dipstick later IPB Image

Plating costs about $15.00 retail per caliper here. You may find cheaper or more expensive. Think about it though, for an additional $30-40 you've got a new factory finish on there... why not? IPB Image
SpecialK
I'll check out some local places, beats the Eastwood Cad paint I used on my fronts. Looks okay, but I'm not sure how it'd hold up IPB Image

This thread needs to be upgraded to "classic" status! IPB Image
IronHillRestorations
QUOTE (Aaron Cox @ Jan 25 2005, 09:18 PM)
sissy boy - uses latex gloves....



This thread needs to be upgraded to "classic" status!

I was going to tell Eric that the blue nitrile hold up better than plain 'ol latex. SAS makes some real HD ones in 14mil.

Us "old guys" with kids like to plan ahead (ie be around for awhile), who knows what kind of cancer you get from brake fluid IPB Image


No doubt Kevin!

Great post Eric.
Gint
Fantastic write up Eric. Thanks for taking the time to do it. I will move this thread to the Classics Forum as soon as it plays out.
tat2dphreak
really makes your service worth every penny to know what you put into it IMO... I think I have an extra set that could use your TLC... probably this summer...
MarkG
Do you have rebuilts in stock or do you need to have ours to rebuild (i.e. estimated turn-around time)?
Eric_Shea
I currently have one set in stock. They go fast. Turn around past that is two weeks.

Some I build on spec. Meaning: If the owner thinks there's stuck pistons etc. I'll usually bring them in and dismantle to make sure I can even work with the core. If not I'll request another core. I can work with most cores. Others want "clear" zinc (silver look) and those are done on spec. as well.

I like to gather all my cores for a trip to the plater, hence the two week wait.
bondo
Awesome! IPB Image You rock!

Is there an easy way to tell if rear calipers NEED rebuilding? Mine don't appear to be leaking, but the last time the car was registered is 1986.
Eric_Shea
Thanks! I'm glad the thread is of interest.

One way to check the status of your calipers is to attempt the emergency brake adjustment. If you can move the pistons then you at least ahead of the game.

If'n it was my car (which it aint) and it had been sitting since 86 then I would simply rebuild them. Seriously, I'm not trying to schlepp a job... 20 years is a bit too long to be sitting. Your pistons are probably frozen.
skline
So Eric, do you sell the little sweaters to put on the calipers to keep them from freezing?? IPB Image
Eric_Shea
I should but then it would cover up their beauty. IPB Image

Wait a minute... was that one of those SoCal, I've got a damn palm tree in my backyard crack at my frozen piston comment? IPB Image

You noticed how this thread was humming right along until Punk-Admin jumped on me as well.

Well I'll have you know... we have a different work ethic here. We don't just run off for a siesta or a jaunt to a booby-bar anytime we damn well please Mister. We have to keep working (with gloves) to stay warm. IPB Image

IPB Image
DJsRepS
That was an fantastic journey through the rebuild process. The most fantastic part I missed is where the begining pic's showed an ugly rusted finish like mine and the ones I want with that fresh out of the box brand new looking finish. How did that happen. I need to do that to my whole rusty car.
Eric_Shea
QUOTE
The most fantastic part I missed is where the begining pic's showed an ugly rusted finish like mine and the ones I want with that fresh out of the box brand new looking finish. How did that happen.


That's where I loosely bolt them back together and bead blast them. They come out as new bare metal. Then it's off to a local plating shop for a fresh coat of yellow zinc.

You could have your teener galvinized... wouldn't be the first. IPB Image
dinomium
Thanks for the timely post! I was just gonna ask what to touque the bolts to..
;^)
Classix!
dinomium
Ok that was too easy!! IPB Image
I will bolt them and the master that I got at root's party in Friday and see if they leak...
Thanks for the great pix!!!
dtd
DJsRepS
Thanks for the reply Eric! those do look great. I never used that zink paint but cant it be got in a spary can from Auto paint supply store. It almost looks like a gold plating sweet!
Eric_Shea
That's the real deal not paint. I can have them yellow (what you see here) or clear (silver) zinc plated. It is the same as the factory finish.

Paint will not hold up under standard operating conditions unless it is a high temperature paint.

QUOTE
Then it's off to a local plating shop for a fresh coat of yellow zinc.
i love porsche
so how much are we talking for one of these rebuilds??
Eric_Shea
Follow the link in my signature. They're sold in pairs for $225.00 plus shipping and your "rebuildable" cores. IPB Image
swood
So do I have all the seals and stuff I need for the rebuild?

Heres a single front set
swood
single rear set

If I'm missing anything I'll need to special order that (them).

Tan-Q! IPB Image
Korijo
how much for rebuilding my /6 fronts (if possible) ?

got 'em off evilbay, from Stromberg... said they've been rebuilt already... hmmm... IPB Image

could you double check ? maybe clear zinc plating, too !
Eric_Shea
Stevo,

You've got everything you need but... you've got your front and rear descriptions mixed up.

The fronts have the new piston/pad positioners.

The Rears have the o-rings. (Tip: Your rear dust cover retaining rings are too big. Get a strong pair of cutters and trim 1/8" past that overlap)

Dave,

We should be able to look at your calipers and tell. Parts and labor would be roughly the same for m-calipers and we could do "clear" (silver) zinc if you wanted.
swood
ach so! So I do. Thanks.
Korijo
QUOTE (Eric_Shea @ Jan 29 2005, 07:38 AM)
Dave,

We should be able to look at your calipers and tell. Parts and labor would be roughly the same for m-calipers and we could do "clear" (silver) zinc if you wanted.

how much for m-caliper rebuild ?

do you mean m-rebuild kits ?

do i need to supply the kit (if needed) ?
Eric_Shea
QUOTE
how much for m-caliper rebuild ?


Parts and labor (time invested, plating, blasting, rebuild kits) are basically the same as the 914 rear caliper. You'll get a slight savings in the rebuild kits. Front M-Calipers would be $225.00

QUOTE
do you mean m-rebuild kits ?


Yes... they're a bit less than the 914 rear kits.

QUOTE
do i need to supply the kit (if needed) ?


Nope... just let me know they're on the way and I can get everything for you.
pete-stevers
Fantastic thread Eric...
can't wait to get the hubs....
Cheers IPB Image
steve
the colonel
fantastic thread. wish me luck. i will soon be either stopping..... or sending you my mistakes. either way it beats rollin through an intersection screaming "OH SH....."
the Colonel
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