Replacing rear rotors and pads

I have printed the info on replacing the pads but is there anything else I need to purchase other than pads and the rotors to do the job? Also, is there more to it than was was mentioned on the pads? Is all I have to do is remove the rotors and put the new ones on? no special pulling tools etc?? someone please tell me if this is a job I can do myself. I am mechanicley inclined.

I recently had the rear brakes on my '76 911S done by my friend. I was right with him watching, if not helping at the same time. As long as you have your basic tools (ie sockets, ratchets, wrenches, impact screwdriver) you are good to go. Whether or not you need other tools, I don't know, as your 911 might be a different year from mine.

Jeff
1976 911S

thanks and by the way, nice user name.

Changing the rotor requires removing the caliper, which necessitates breaking the fluid lines loose, so a complete fluid change is called for! All four calipers SHOULD be removed and drained completely!!! Flare nut wrenches are the CORRECT tools to use on the fluid line connections and bleeder screws! Metric flare nut wrenches are available from Sears, and other sources. Do not proceed with caliper removal without these REQUIRED tools! The fluid lines at the master cylinder should be removed, and blown out with compressed air, one side at a time, as the caliper is removed for that side ... finish the draining, rotor replacement, then replace caliper, and proceed to other side! This is a COMPLETE fluid replacement, not just a top-up and bleed! Porsche recommends fluid changes at a two-year interval, but very few owners do it!!! Be sure to inspect the four rubber hoses for damage, visible cracking, etc.

Depending on the amount of water the rear rotor has been through, it can be easy or hard to get off! The required tool is a precisely fitting slotted screwdriver bit for the two retaining screws. Do not use a bit that is TOO SMALL!!! If necessary, buy a new bit that is slightly large and grind/file to fit precisely. Once the retaining screws are out, the rotor should come off easily. A plastic mallet tapping at the outside periphery of the rotor, alternately on opposite sides may help loosen a stubborn rotor! Next, put two 8 mm x 1.25 mm bolts in the two threaded holes in the rotor 'hat' area, and apply torque evenly! If it does not budge yet, apply heat with a propane torch to the axle flange area in a circular pattern, and vary continuously flame position for five minutes.

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Warren Hall
1973 911S Targa

Thanks Titanium Pipe, you've got a cool user name too. When I had my rear brakes done, I didn't do what Warren recommends as the complete fluid change. All I had was the rear brakes bled. I had the car on jack stands for over a week and couldn't wait to drive it, so me and my friend just did what was really needed(rear brake pads were almost gone, metal grinding against rotor). I will probably clean out everything next time...and yes do replace your brake lines if they aren't what they used to be. I believe the wrench you need to take of the caliper was a 19mm...it'll take a while to get to. Good luck!

Jeff
1976 911S

I have a follow up question (or two) if you will?

On brake bleeding: Obviously, topping off and bleeding does not accomplish a full fluid change? Is it effective enough to simply keep bleeding - and bleeding and bleeding - until the fluid has completely cycled out the old so that only fresh fluid is coming through the calipers?

On changing brake lines: I've seen that replacing brake lines on a 964 requires an electronic "reset" to be performed on the computer / braking system. I can't think of any way that the system would even know if the lines were replaced. What's up with this? Is a reset really required? If so, can it be done "manually?

Thanks all,
Brian Smith
91 C2

The reason bleeding, topping up, and pumping completely until fresh fluid comes out the nipples at each caliper ... isn't adequate is simply that 75 to 80% of the old brake fluid just sits there 'pooled' in the caliper! Unless you unbolt the caliper, disconnect the line, take it off the car, and turn it upside-down and drain out all of the old fluid, and even blow it out with compressed air ... gravity dictates that the fluid will just sit there!

One CAVEAT: I don't know what the factory manual has to say for ABS-equipped cars regarding bleeding, or changing the fluid, so I suggest you acquire and read the manual, or contact your dealer to discuss the specifics of a fluid change per factory instructions ... and I suggest you ask how the 'old' fluid in the caliper gets changed if you don't remove and drain each individual caliper??? The laws of physics don't change, just because there is an ABS-controller watching over things!

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Warren Hall
1973 911S Targa

While doing all that work certainly wouldn't hurt, I have owned many old cars over the last few decades, and have just flushed the fluid every year or so using the standard method, and have never had a caliper go bad, even on cars that are now 30 years old with almost 300,000 miles.

Everyone should do what they think is best, but I'll personally just stick with my regular brake fluid changes, rather than go through a huge amount of work to prevent a problem that has never occured to me in decades of driving old cars. Especially when the preventative measure is only slightly less burdensome than the cure!

Just my own personal opinion and way of doing things, YMMV, FWIW, etc. etc.