badass7

My front left pad is down very very low. To the point where is will scrape if I press on the brakes hard enough. I was wondering if I could just get away with replacing the pads for now without doing anything to the rotors. Would not turning the rotors or replacing them just cause the pads to wear out faster?? How do you know when your rotors need to be turned?? Rx-7 budget is tight at the moment and would rather spend just $ 50 now and the $150 + for new rotors and another $50 for the pads again when replacing the rotors. Thanks guys!

maxpesce

No - If the rotors are smooth to the touch w/ no scoring and are not warped then they don't need to be turned - also you don't have to replace the pads when turning rotors - just sand the friction face w/ coarse sandpaper so they will bed in again properly

badass7

Thanks for the response Max !!

coop

ARe there any special break tools needed to replace the rotors? Also, while I am in there, should I get steel braided breaklines?
Thanks
-Dave

BrianK

Can't say anything about the steel lines, but I just replaced my fronts. They required no special tools. I did it with some very large channel locks and a screwdriver.

Couple tips:

1. You don't need to unscrew anything! The two pins that look like regular head screws are just pins - they have a slot that's just to make it easier to turn the pin to line them up for the spring when you're reassembling. If you do try to turn them while the spring is in, it'll bend the spring.

2. There are two pistons that need to be pushed back to fit in the new pads. Mazda recommends a special tool that will push back both pistons at the same time - it isn't necessary. A large set of channel locks with work as long as you push the piston back slowly. Also, they don't require a lot of force to move, but if they are all the way out, they may require a delicate touch to get them started, so don't force them (you can scrwe them up if you do). It may speed the job up if you brace one pad with the screw driver while you push in the other (but it isn't necessary as long as you push them in slowly).

BrianK

oh uhm... you said replace the rotors... I just told you how to replace the pads. my mistake.

Flybye

Even if the rotors don't have scratches on them, they still could be warped. When you brake, do you get heavy vibration from the brake pedal or steeringwheel?

One good test is to simply jack up the car and move the tire round-n-round. If you hear the pads hitting only one section of the rotor at a time, then it's time to cut them. Also, take the wheel off and the pads. Without pads, the rotor should spin fairly easy. Now, spin it around and look at it through the brake caliper. Obviously, the caliper isn'y going to move and is poerfectly fixed. If you see the rotor even slightly wobbling back and forth, then that means it is warped.

What causes brake rotors to become warped? Heat, of course. Just think what rotors have to go through. Just imagine what a rotor must suffer like when under braking, the rotor is super hot, and then you hit a puddle of water.

coop

Yea, I can hear them, they go "cree-ch cree-ch cree-ch" when I press the breaks (the rear ones) and it is directly related to the speed, and if I press hard on the breaks they don't do it.
Should I replace the pads while I am in there?
-Dave

ronarndt

Badass7- If you are going to press the caliper pistons back in with channel locks or anything which could slip, be careful you don't knick the rubber dust boot which goes around the piston, otherwise a job that should take 30 minutes will take you a couple hours to install a rebuild kit on the caliper. A better way, if you don't have the special service tool, is to use two large C clamps per piston pressing on a thin piece of wood or metal plate, since you also need to press uniformly on the piston so it does not tilt slightly and sieze. The clamps will also not slip suddenly and cut the dust boot. If you are doing all four brakes, periodically check your master cylinder reservoir. As you press back the pistons, you will probably need to remove some brake fluid so it does not spill all over your engine compartment and inner fender- brake fluid will remove your paint quite nicely. Ditto on not having to turn the rotors unless they are scored or warped. This is the classic rip-off if you have a brake job done at a dealer or many of the repair chains. If they turn the disc and don't get it mounted properly on the lathe, it can be worse than when they started. Plus- every time you turn the disc, you lose thickness and strength.