DIY Brake servo (booster) re-build with new o-rings and anew shaft seal

[master6]

For the following cars 735,533,535,m535,m5,633,635,m635,m6.

This Do It Yourself (DIY) is to re-build the Brake Servo Booster #34331156925
It includes a step by step procedure to repair the internal rubber seal and 5 o-rings.
I just up dated this post DIY, I have added a new shaft seal and a how to replace the seal.

Read the captions at the bottom of each photo.

https://picasaweb.google.com/1135658...nZ_Z7f6JrUyQE#

This repair needs to have the booster removed from the car.

Tools needed: Dremal, vise, bench grinder, battery drill motor with reverse, 1-1/8 inch deep socket, 13mm 1/4 in drive socket with an extension into the drill motor, blade screw driver, 10mm drill bit or 3/8 inch metal drill bit, electric drill motor with 3/8 chuck.

[Shogun]

thanks for that valuable info. Better leave a contact email address here and the price if someone wants to order from you
thanks

[master6]

Thanks Shogun,

If you want to save some money, you can re-build your own brake servo booster,
(only on the E32, 735 cars)
I have a complete DIY guide to do the repair, its is free, no charge for the info.

Please go to the link and read the captions at the bottom of each picture. The kit costs $ 18.90, contact me at my e-mail, jay_c_stratton at hotmail.com

link https://picasaweb.google.com/1135658...nZ_Z7f6JrUyQE#

Also for e24, and e28

[Shogun]

I just used the part number you mention in cross reference on realoem, and interestingly this part number is used on different cars by country spec., if I use the US English search the following comes out

Part Cross-reference RealOEM.com Home
Part 34331156925 (Brake servo unit) was found on the following vehicles:

E24: Details on E24
E24 633CSi Coupe
E24 635CSi Coupe
E24 M6 Coupe


E28: Details on E28
E28 533i Sedan
E28 535i Sedan
E28 M5 Sedan


E32: Details on E32
E32 735i Sedan
and now, surprise, surprise, the German language search:


Teil 34331156925 (Bremskraftverstärker) wurde in folgenden Fahrzeugen gefunden:

E24: Details zu E24
E24 628CSi Coupé, Europa
E24 635CSi Coupé, Europa
E24 M635CSi Coupé, Europa


E28: Details zu E28
E28 525i Limousine, Europa
E28 528i Limousine, Europa
E28 535i Limousine, Europa
E28 M5 Limousine, Europa
E28 M535i Limousine, Europa


E32: Details zu E32
E32 730i Limousine, Europa
E32 730iL Limousine, Europa
E32 735i Limousine, Europa
E32 735iL Limousine, Europa
E32 750iL Limousine, Europa


That means, my 11/1988 Japan spec. E32 750 which has the same brake booster as the German spec. 750 would fit for your repair kit, very good to know.
BUT, for all not so much in the know of details, this refers only to 750 up to built year
Für Fahrzeuge mit Länderausführung Japan L807A=Ja
Bremskraftverstärker ATE up to built month/year 12/1990 34331156925
http://www.realoem.com/bmw/showparts...5&hl=5&lang=de

that means, that is for the 750 brake booster with small brakes, not the German Autobahn brake on the 750 with 4-pod calipers which was supplied after 12/1990.

[master6]

I just used the part number you mention in cross reference on realoem, and interestingly this part number is used on different cars by country spec., if I use the US English search the following comes out

Part Cross-reference RealOEM.com Home
Part 34331156925 (Brake servo unit) was found on the following vehicles:

E24: Details on E24
E24 633CSi Coupe
E24 635CSi Coupe
E24 M6 Coupe


E28: Details on E28
E28 533i Sedan
E28 535i Sedan
E28 M5 Sedan


E32: Details on E32
E32 735i Sedan
and now, surprise, surprise, the German language search:


Teil 34331156925 (Bremskraftverstärker) wurde in folgenden Fahrzeugen gefunden:

E24: Details zu E24
E24 628CSi Coupé, Europa
E24 635CSi Coupé, Europa
E24 M635CSi Coupé, Europa


E28: Details zu E28
E28 525i Limousine, Europa
E28 528i Limousine, Europa
E28 535i Limousine, Europa
E28 M5 Limousine, Europa
E28 M535i Limousine, Europa


E32: Details zu E32
E32 730i Limousine, Europa
E32 730iL Limousine, Europa
E32 735i Limousine, Europa
E32 735iL Limousine, Europa
E32 750iL Limousine, Europa


That means, my 11/1988 Japan spec. E32 750 which has the same brake booster as the German spec. 750 would fit for your repair kit, very good to know.
BUT, for all not so much in the know of details, this refers only to 750 up to built year
Für Fahrzeuge mit Länderausführung Japan L807A=Ja
Bremskraftverstärker ATE up to built month/year 12/1990 34331156925
http://www.realoem.com/bmw/showparts...5&hl=5&lang=de

that means, that is for the 750 brake booster with small brakes, not the German Autobahn brake on the 750 with 4-pod calipers which was supplied after 12/1990.

Hey Shogun,

That is very interesting from the German Realoem.

The info that I got from our USA realoem, shows a different part # for the 750 e32. # 34331161772

Part 34331161772 (Brake servo unit) was found on the following vehicles:

E31: Details on E31
E31 850Ci Coupe
E31 850CSi Coupe


E32: Details on E32
E32 750iL Sedan

I think that there is a slight difference in the size of one o-ring, on the 750/850.

The o-ring closest to the fire wall may be a slightly larger size. I think that all fof the other parts are the same and interchangeable.
I do not feel confident to recommend my repair kit for the 750, or the 850, just yet.

I need to get my hands on this booster from a 750, 850. And take it apart and measure the internals.

Thanks, Jay

[Shogun]

Hi Jay
I believe you are right. The E31 and E32 750 EURO design with 4-pod has a slightly thicker shafts as far as I remember when we last disassmbled one from an E32 750 Alpina B12 with 4-pods calipers.
But better get your hands on one to reconfirm it.

[master6]

Hi forum members,

For the 735 only.

I located a supplier for the internal white teflon (2) piston rings. I should have them in about 15 days.

I also found a supplier for the internal shaft seal at a lower price, 9.5mm I.D. This will take about 8 weeks to manufacture.

Then I will have all of the interior replacement parts, a complete repair kit, for the brake servo/booster.

Here is the photo link to the DIY re-build.

https://picasaweb.google.com/1135658...nZ_Z7f6JrUyQE#

Read the captions at the bottom of each photo.

I also added a new helpfull hint for the re-build.
Where the grub screw, screws into the booster cylinder there can be a burr created by the grub screw, on the interior. This burr can cut the 38mm O-ring, and also damage the 2 white high pressure teflon piston rings.
Thanks to (tn).

When I receive these new parts, I will revise the price.

[master6]

Hi Forum Members,

For the 735 ONLY!

I now have all of the interior components for the complete re-build of the Brake Servo (booster). I have received the new teflon interior high pressure piston o-rings. 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 5 internal rubber o-rings, the 2 teflon piston o-rings, and a new shaft seal.

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.

The new price is $24.95 + shipping $1.95 USA, TOTAL $26.90 USD.

International is also $24.95 + shipping $3.95 International TOTAL $28.90 USD.

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

https://picasaweb.google.com/1135658...nZ_Z7f6JrUyQE#

I am also offering a QUICK FIX kit, this includes just the 38mm o-ring, and the shaft seal only. Price is $7.95 + $1.95 shipping USA TOTAL $9.90 USD.
International is also $7.95 + $3.95 shipping International TOTAL $11.90 USD.

[master6]

Hi Forum Members,

For the following BMW cars
e28,533,535,m535,m5, part # 34331156925
e24,633,635,m635,m6,L6, part # 34331156925
e32,735 only. part # 34331156925

e23,733,735,745 part # 34331152825

This Do It Yourself (DIY) is to re-build the Brake Servo Booster, all of the 10 piece interior repair kit are identical, for both part numbers

I recently rebuilt another hydraulic brake servo booster, and I was amazed at how the rubber o-rings were deformed and hardened. 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/1135658...nZ_Z7f6JrUyQE#

I am now offering to rebuild your booster for you, using my 10 piece repair kit.
I am charging $85.00 + shipping back to you. Cont USA only. USD
If you send me your address, and I can give you an accurate shipping quote, via FedEx Ground home delivery.
Just send your booster to me, with a $ check. PayPal add 4%

I also have a couple of spare rebuilt booster, that I can send to you. And you return your old core to me, shipping on you.
Same price of $85.00 + ship + $60.00 core. USD
PayPal add 4%
jay_c_stratton@hotmail.com

_________________
Jay
1987 M6
https://picasaweb.google.com/1135658...X_js7i1IyIgAE#
Booster rebuild
https://picasaweb.google.com/1135658...nZ_Z7f6JrUyQE#

[master6]

Hi Forum Members,

I added the 750.

For the following cars, that have a Hydraulic brake servo booster, and ABS.

e28, 525,528,533,535,m535,m5;
e24, 628,633,635,m635,m6,L6;
e32, 730,735,750;
e23, 728,730,732,733,735,745;

This Do It Yourself (DIY) is to re-build the Brake Servo Booster #34331156925.
On the e23 it is part # 34331152825
The e23,e24,e28,e32 735 all of the 10 piece interior repair kit are identical., for both part numbers.

The e32 750 has a different part # 34331161772,
It uses a shaft seal instead of an o-ring at the firewall end. And is slightly more expensive.

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/1135658...uthkey=Gv1sRgC KnZ_Z7f6JrUyQE#

BOOSTER REPAIR SERVICE

I am now offering to rebuild your booster for you, using my 10 piece repair kit.
For the e23,e24,e28,e32(735).
The price is $85.00 + 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.
And I will send you my address.
Just send your booster to me, with a $ check.
You insure for $175.00
PayPal add 4%.

I can also rebuild your e32 750 booster for $95.00 + shipping back to you.
Cont USA only, USD.
You insure for $220.00
PayPal add 4%

REBUILD WITH CORE

I also have a couple of spare rebuilt boosters, and I can send one to you.
For the e23,e24,e28,e32(735).
And you return your old core to me, shipping on you.
Same price of $85.00 + ship + $60.00 core. Cont USA only, USD.
You insure for $175.00
Core charge refunded via PayPal.
PayPal add 4%

I also have a spare e32 750 booster that I can send to you,
for $95.00 + ship + $95.00 core.
Cont USA only, USD.
Core charge will be refunded via PayPal.
You insure for $220.00
PayPal add 4%

Send me an e-mail to get started jay_c_stratton@hotmail.com

PICT0001.jpgPICT0003-001.jpg

[master6]

DIY brake servo booster repair kit and rebuild service.

Please read the captions under each photo.

https://picasaweb.google.com/1135658...nZ_Z7f6JrUyQE#

[master6]

Hello e32 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/113565887645138328387/BrakeServoBoosterReBuild5NewORings?authkey=Gv1sRgC KnZ_Z7f6JrUyQE#

Thank you,

P4190001.JPGP4190003-001.JPGP4190004-001.JPG