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o ring

Discussion in 'E31 (1991-1997)' started by 91900, May 14, 2008.

    91900 guest

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    Yep, I have to do the dreaded brake booster o-ring repair.
    Can someone send me a brake booster diagram from a Bentley, Hanes or other tech manual. I'm living in Dubai, and we don't have a NAPA store where I can get the o-ring, so I have to look around for a few days to find one. I'll probably end up Fed-Exing the part from Canada.

    mlweaver guest

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    Hi Dave,
    The brake booster is "not serviceable" - therefore you can't find a diagram of it.
    It is an ATE part, if you choose to replace it.
    If you choose to repair it (as I did), I suggest that you go ahead and completely remove it from the car (by disconnecting the brake pedal). It is much easier to work on the booster "on the bench" than inside the car.
    This forum will not allow me to link to an outside URL (or I can't figure it out:confused:) - but you can find a write up at world wide web dot E31FAQ dot com. Follow the links to the "brake" section - booster o-ring repair - you are looking for a .pdf attachment (att89) (thank you, Jon).
    The most important thing to know is that once the master cylinder is removed from the booster, only the small "one-way" screw on the bottom of the booster is holding the GIGANTIC spring in place. The black plastic "cap" inside the end of the booster is under HIGH pressure from the spring, and removing the retaining screw (requires sharp vice-grips) will LAUNCH all the parts inside the booster across the room! You must hold a rag over the end of the booster and control that spring when loosening the retaining screw. Then you can see how all the parts go together (black cap, spring, push rod, metal cup, o-ring and washer). If you see how they go together, the repair is simple!
    Keep that Dubai sand out of the brake system, and good luck!

    91900 guest

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    Thanks Mark, I have a couple of write ups from roadfly. I have(had) a diagram on my laptop that, unfortunatley my daughter dropped about a week ago. I found the o-ring today and get to start on it tomorrow morning. I'm more of a pictorial type than text!
    I hope it's easier than it sounds!
    • Member


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    8 series parts info

    Check out these links Dave. Plenty of info and you can order your parts from Gault BMW and have shipped to you.




    - Scott

    bmw art car guest

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