View Full Version : DIY Hydraulic brake servo booster, 10 piece repair kit, e24,e28,e23,e32,(735 only)

12-01-2012, 11:46 PM
Hi Forum Members,

EDIT: 2-8-13, I have made some recent changes in the DIY repair kit and rebuild service.
Please refer to my DIY link.

https://picasaweb.google.com/113565887645138328387/BrakeServoBoosterReBuild5NewORings?authkey=Gv1sRgC KnZ_Z7f6JrUyQE#

For the following cars, with Hydraulic brake servo booster, and ABS.

e24, 628,633,635,m635,m6,L6;
e28, 525,528,533,536,m535,m5;
e23, 728,730,732,733,735,745;
e32, 730,735,750;

I now have of the interior components for the rebuild of the brake servo booster. I installed these new parts into my M6 over the weekend. The road test was a success, all of the parts work as they should!

The new up-graded kit includes the 6 internal rubber o-rings, a 9.5mm I.D. shaft seal. 7 pieces total.

I have also up-graded the Picasa Link, I took more photos and added more captions to show the correct method that I used in the assembly of the booster.

Here this the link to the DIY, and the current pricing, and the step by step instruction, of the booster repair.

Please read the captions at the bottom of each photo.

https://picasaweb.google.com/1135658...nZ_Z7f6JrUyQE# (https://picasaweb.google.com/113565887645138328387/BrakeServoBoosterReBuild5NewORings?authkey=Gv1sRgC KnZ_Z7f6JrUyQE#)

Dremal hobby tool at Home Depot $69.00 this is a must have tool to do this job correctly! The Dremal is variable speed.
Rotary Tool Kit-3000-1/25H at The Home Depot (http://api.viglink.com/api/click?format=go&key=9471fc9a94e73595983f2ab94f973065&loc=http%3A%2F%2Fwww.bimmernut.com%2Fforum%2F5-series-bmw%2F44196-diy-hydraulic-brake-servo-booster-10-piece-repair-kit-e28-e24-e23-e32-735-only.html&v=1&libid=1354422898597&out=http%3A%2F%2Fwww.homedepot.com%2Fh_d1%2FN-5yc1v%2FR-203040434%2Fh_d2%2FProductDisplay%3FcatalogId%3D10 053%26langId%3D-1%26keyword%3Ddremel%26storeId%3D10051&ref=http%3A%2F%2Fwww.bimmernut.com%2Fforum%2F5-series-bmw%2F&title=DIY%20Hydraulic%20brake%20servo%20booster%2C %2010%20piece%20repair%20kit%2C%20e28%2C%20e24%2C% 20e23%2C%20e32%20(735)%20only&txt=Rotary%20Tool%20Kit-3000-1%2F25H%20at%20The%20Home%20Depot&jsonp=vglnk_jsonp_13544229686252)

EDIT: 12-12-12

This Do It Yourself (DIY) is to re-build the Brake Servo Booster # 34331156925. For the e23,e24,e28,e32-735.
On the e23 it is part # 34331152825
The e23,e24,e28,e32 735 all of the 7 piece interior repair kit are identical, for both part numbers.

On the e32 750 there is a different part # 34331161772.
It has a shaft seal to replace the standard o-ring at the firewall end,
and this shaft seal is more expensive than the o-ring.

I recently rebuilt another hydraulic brake servo booster, and I was amazed at how the rubber o-rings were deformed. They are now an oblong shape. The large o-ring 38.0mm x 3.0mm, at the front of the booster. It now measures 2.55mm high instead of 3mm. And is 3.28mm thick, were it should be again be 3.0mm. And it is noticeably more brittle. The smallest o-ring was brittle and it broke when removed.

https://picasaweb.google.com/113565887645138328387/BrakeServoBoosterReBuild5NewORings?authkey=Gv1sRgC KnZ_Z7f6JrUyQE#


I am now offering to rebuild your booster for you, using my 6 piece repair kit.
For the e23,e24,e28,e32-735.
The price is $80.00 + shipping back to you. Cont USA only, USD.
If you send me your address, I can give an accurate shipping quote.
Via FedEx Ground home delivery, with tracking.
I will then send you my address.
Just send your booster to me, with a $ check. You insure for $190.00
PayPal add 4%

On the e32 750, please refer to my DIY link.


I also have a couple of spare rebuilt boosters, and I can send one to you.
And you return your old core to me, return shipping on you.
Price is $80.00 + ship + $75.00 core. Cont USA only, USD.
You insure for $190.00
When the core is returned, the Core deposit will be refunded via PayPal.
PayPal add 4%.

On your e32 750, please refer to my DIY link.

Send me an e-mail so we can get started, jay_c_stratton@hotmail.com


04-22-2013, 12:31 AM
Hello fellow e24 owners,

Parts Geek and its supplier A-1 Cardone, are selling bad rebuilt hydraulic brake boosters.

I had a client of mine who sent me a leaking booster. When I opened it up to repair, I noticed that it had an incorrect shaft seal installed.

On top of that, the shaft seal was installed up-side down, and missing the garter spring.

My client told me that his first Cardone from Parts Geek leaked as soon as it was installed, he sent it back to Parts Geek and they sent him another.

When he installed the second one, it also leaked.
And thats when he called me, and I used my rebuild service and sent him one of my rebuilt spares.

When I received his core back, I set to rebuild it for the next client.
I was shocked, the shaft seal was upside down, I then pressed the shaft seal out of the black plastic cup. The shaft seal specs are 9.5mm i.d. x 22.0mm o.d. and thickness of 6mm.
The A-1 Cardone is 10.0mm i.d., way too big. It is made in China by YEI Shien, part #A19168 10x22x6.
Because it was in backwards the garter spring came off, or was never there in the first place.
I am going to also attach some photos, of the suspect seal front and back, and what a garter spring looks like.

Here is my link, booster repair kit and rebuild service.

https://picasaweb.google.com/1135658...nZ_Z7f6JrUyQE# (https://picasaweb.google.com/113565887645138328387/BrakeServoBoosterReBuild5NewORings?authkey=Gv1sRgC KnZ_Z7f6JrUyQE#)

Thank you,