Brake overhaul

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The brakes on the Z were fairly intimidating at first, but they are easy to understand once taken apart. The front calipers and pads are larger than the rear, and the wheel bearings are sealed in the back, while the front bearings require repacking every now and then. The Hayne’s manual is useful for working on the brakes, as it has relevant pictures and instructions. I took the front brake system entirely apart and put it back together with the new parts (somewhat) easily, and that was my first time even taking the wheels off the car.

The rotors were worn beyond the point that I could cut them, so I had to replace them. I bought a pair of new rotors at NAPA, along with a new loaded front-left caliper, and new brake pads. Here are some pictures of all four rotors / calipers:

Front right rotor:


Front left rotor:


Rear right rotor:


Rear left rotor:


The bolts that connect the caliper to the hub were possibly the toughest I have had to remove from the car. I spent an easy half an hour trying to break one bolt loose, which included the use of Liquid Wrench. I bought and promptly broke two 24″ breaker bars from PepBoys, along with a Craftsman adapter. The people at Sears were curious how I managed to break an adapter I just purchased an hour earlier, and I ended up giving in and buying a quality 24″ Craftsman breaker bar and some 1/2″ sockets that did the trick. The adapter casualty:


In this instance a lot of time and trouble could have been saved if I had the right tools from the start of the project. I’ve slowly assembled an assortment of tools over the years, but a quality breaker bar and sockets are worth their cost several times over. Here are the two bolts that caused the biggest headaches:


To remove the rotors and hubs / bearings, you need to remove a cotter pin, a retaining nut and cover, and a slide piece, then the rotor should slide off the spindle.

The driver’s side:


And the pass. side:


The rotors were heavily rusted everywhere except the contact areas, and there were actually small spiders inside one of the caliper pistons.


It took a little while to realize that the wheel bearing on the pass. side did not come out like the driver’s side. Here is the bearing left on the spindle:


Initially, I tried to use a vacuum pump from AutoZone that claimed to allow ‘Easy, one-man brake bleeding’. After some frustration, I found out that these don’t really work, and I had to grab a buddy to work the brakes the old-fashioned way. The bottle on the left was the fluid that I drained first, then the bottle on the right was presumably some of the newer, cleaner fluid that was also bled.


I bought new front rotors at NAPA for a reasonable price, and installed the old hubs and bearings in a few minutes. Hand-packing the wheel bearings was an experience, but once again the Hayne’s manual pulled through and actually provided useful information, so the procedure was a simple (yet messy) one.


Several weeks later I decided to address an issue that had been cropping up, and other 3ZC forum members had also experienced. While moving in reverse, if one tapped the brake pedal lightly, there would be a loud, moaning noise coming from the rear brakes. It was embarrassingly loud, and mostly occurred when pulling out of a parking space or backing down the driveway. Per the suggestion of my mechanic buddy, I took apart the rear caliper slide pins on each side. I used a small packed of caliper lube from PepBoys and cleaned then re-lubed each pin. Since lubing the pins, I have heard the noise faintly only once.

After a few weeks I noticed, especially at low speeds, that a squeaking sound was coming from the brakes when they weren’t engaged, and the sound disappeared once I tapped the brakes. A quick consultation revealed that I had neglected to lube the backings on the pads, and a dollar of lube and an hour resolved that issue.

Currently, the brakes now operate smoothly, with no noises or inconsistent operation. If I slam on the brakes, all four wheels lock, which should be sufficient for normal street operation. The new pads, rotors, and loaded caliper are all holding up nicely as well.

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