This article is one in a series that have been released in conjunction with Wayne's new book, 101 Performance Projects for Your BMW 3 Series. The book contains 272 pages of full color projects detailing everything from performance mods to timing the camshafts. With more than 650+ full-color glossy photos accompanying extensive step-by-step procedures, this book is required reading in any 3 Series owner's collection. The book was released in August 2006, and is available for ordering now. See The Official Book Website for more details.
I don't know if this happened to you or not, but did you ever park your car on a hill, only to slowly see it start rolling away after you come out of the store? Granted, this is a worst-case scenario, and how many people don't put the car in gear while parked? Regardless, the parking brakes eventually wear down over time, causing them to become ineffective in holding the car when parked. In this tech article, I will go over the relatively easy steps involved in adjusting the parking brakes on the BMW E30 3 Series models from 1984-92. Keep in mind that this article is specific to cars with rear disc brakes. The 318i from 1984-86 uses rear drum brakes. The procedure for adjusting them is the same as well.
Parking brakes work essentially like a drum style brake. There are two shoes mounted on the inside of the brake rotor. When you pull up on the handbrake, it drives the shoes outward, causing them to grip the inside of the brake rotor. Over time, friction wears the shoes down, causing them to not grip the inside of the rotor. The solution is to re-adjust the shoes so that they again come into contact with the rotor.
Here's how it is done. Start off by chocking the front wheels. This will keep the car from rolling when you jack up the rear wheels, which is the next step. For those of you not familiar with jacking up the rear end, I highly recommend you check out Wayne's article on jacking up your BMW.
Be sure to jack the car up on a structural member. Otherwise, you risk damaging the chassis. I have seen jacks go through floorboards on cars before. Also be sure to support the car on jack stands. NEVER rely on a jack to keep the car up in the air.
Once jacked up, put the car in neutral, release the handbrake and pump the brakes a few times to seat the pads. Remove the rubber boot around the handbrake. You will now see two nuts in front of the lever. These nuts are used to adjust the parking brake. Slowly pull up on the handbrake until it clicks five times. Once it clicks five times, it is in the correct position to be adjusted.
Now have a helper turn the rear wheels. The idea here is to turn the adjusting nuts until the rear wheels just stop turning. Be sure use turn each nut in equal turns until both wheels begin to drag and stop. Once they stop turning, release the handbrake and check that the wheels spin freely.
Once they spin freely, Spray a little WD-40 over the parking brake mechanism. This will keep things nice and lubricated. Now re-install the rubber boot around the assembly and lower the car.
And that's it, you're done!
Well, there you have it - it's really not too difficult at all. If you would like to see more technical articles like this one, please continue to support Pelican Parts with all your parts needs. If you like what you see here, then please visit our online BMW catalog and help support the collection and creating of new and informative technical articles like this one. Your continued support directly affects the expansion and existence of this site and technical articles like this one. As always, if you have any questions or comments about this helpful article, please drop us a line.