Wingnut
Top Post Dawg
Front Brake Job \'How To\'
Well, I did it again. I did a brake job for a member today and as usual, I had to document it for all to see. It really is not difficult and can save many of you an expensive visit to the dealer for this rather simple job.
Tools required:
LARGE phillips(star) head screwdriver or bit
Large flat head screwdriver or prybar
7mm Allen key or socket
Wire brush or a drill & wire wheel
File
Can of antiseize
First step is to jack up & remove the front wheel. Use a jackstand for safety. Once it is up and the wheel is removed, remove the dust caps from the slider bolt rubber boot:
Then remove the slider bolts with the 7mm Allen key or socket:
Before removing the caliper from the spindle, you need to compress the piston so that it will fit around the new rotor with the new thicker pads. If you are replacing the rotor, no need to worry about scratching up the old one. Just stick a screwdriver or prybar in and pry the piston back. If you are not replacing the rotors, you can pry between the old pad & the piston, but be careful not to damage the piston. You will need to pry it all the way back into the caliper until it won't go any farther.
(update: As mentioned by another member, it may be a good idea to open the bleed screw a little while compressing the caliper. This will bleed the dirty fluid out of the caliper instead of back through the lines.)
Now you can remove the caliper. I use an old coat hanger to hang the caliper on the front spring to hold it out of the way, but also to keep tension off the flex brake line. Now, if your not replacing the rotors, skip the next step (but for the price of new ones, I recommend replacing them). You need to remove the set screw. This is a small screw and is often seized in place, so you need a proper sized bit to make sure you don't strip the head. I put the bit in and whack it with a hammer to help loosen it a bit.
Once the rotor is removed, check the hub surface. If there is a buildup of rust, use a wire brush or wire wheel on a drill to clean it up. You do not want pieces of rust sandwiched in behind the new rotor to throw it out of round.
The old pads just pop out of the caliper. You may need a screwdriver to pry off the old ones, but they are not that difficult to remove. Then replace them with the new ones. The one with the wear indicator goes on the drivers side. Sorry, I forgot to snap a picture of this part. I will when I do my next brake job and edit this post.
Next step is to clean the sliding surfaces. The caliper has to slide back and forth as the brakes are pressed & released. As the friction material(pads) wear, the position of the caliper adjusts and can travel as far as an inch from the time the pads are new to the time they are replaced. I use a file to clean the mating surfaces and apply some antisieze to these surfaces.
You also want to lubricate the slider bolts. Clean them up and apply some antiseize to them before reinstaling them. This will allow the caliper to slide freely and help prevent dragging brakes do to a stiff slider.
I also apply some antiseize to the hub where it mates to the rotor. Again, I forgot to take a pic of that part, but will next time.
Finally, replace everything. Hook the caliper back on the bottom slider bar and rotate into place. Then tighten down the slider bolts. The torque specs are 28Nm (21 ft-lb). The small screw that holds the rotor is 4Nm (35 in-lb). But that little thing just needs to be snug. It just holds the rotor in place so the holes line up when installing the wheel.
Here is the finished product:
And here is a pic of the new & old rotor. You can see where the inside of the old one only used 2/3 of the friction surface. This rotor would have needed machining to be used again. And as mentioned before, new rotors are quite cheap and only a little more than the cost of machining the old ones. Not to mention the downtime while getting them machined, so just replace them and save yourself time & hassle.
Total time to do each side was around 30 min, but allow yourself an hour and a half to do the job if its your first time. Take your time and enjoy the 'getting your hands dirty' experience while you use the $100 or so you saved to buy something nice for your car /images/graemlins/smile.gif
If I forgot anything or if anyone has any additional tips or want to add anything, feel free to let me know and I will update this thread. Good luck.
PS, I was going to do a 'how to for the rears, but it seems someone has already done one. Here is the link for the one Cosmic did. Good work.
Well, I did it again. I did a brake job for a member today and as usual, I had to document it for all to see. It really is not difficult and can save many of you an expensive visit to the dealer for this rather simple job.
Tools required:
LARGE phillips(star) head screwdriver or bit
Large flat head screwdriver or prybar
7mm Allen key or socket
Wire brush or a drill & wire wheel
File
Can of antiseize
First step is to jack up & remove the front wheel. Use a jackstand for safety. Once it is up and the wheel is removed, remove the dust caps from the slider bolt rubber boot:
Then remove the slider bolts with the 7mm Allen key or socket:
Before removing the caliper from the spindle, you need to compress the piston so that it will fit around the new rotor with the new thicker pads. If you are replacing the rotor, no need to worry about scratching up the old one. Just stick a screwdriver or prybar in and pry the piston back. If you are not replacing the rotors, you can pry between the old pad & the piston, but be careful not to damage the piston. You will need to pry it all the way back into the caliper until it won't go any farther.
(update: As mentioned by another member, it may be a good idea to open the bleed screw a little while compressing the caliper. This will bleed the dirty fluid out of the caliper instead of back through the lines.)
Now you can remove the caliper. I use an old coat hanger to hang the caliper on the front spring to hold it out of the way, but also to keep tension off the flex brake line. Now, if your not replacing the rotors, skip the next step (but for the price of new ones, I recommend replacing them). You need to remove the set screw. This is a small screw and is often seized in place, so you need a proper sized bit to make sure you don't strip the head. I put the bit in and whack it with a hammer to help loosen it a bit.
Once the rotor is removed, check the hub surface. If there is a buildup of rust, use a wire brush or wire wheel on a drill to clean it up. You do not want pieces of rust sandwiched in behind the new rotor to throw it out of round.
The old pads just pop out of the caliper. You may need a screwdriver to pry off the old ones, but they are not that difficult to remove. Then replace them with the new ones. The one with the wear indicator goes on the drivers side. Sorry, I forgot to snap a picture of this part. I will when I do my next brake job and edit this post.
Next step is to clean the sliding surfaces. The caliper has to slide back and forth as the brakes are pressed & released. As the friction material(pads) wear, the position of the caliper adjusts and can travel as far as an inch from the time the pads are new to the time they are replaced. I use a file to clean the mating surfaces and apply some antisieze to these surfaces.
You also want to lubricate the slider bolts. Clean them up and apply some antiseize to them before reinstaling them. This will allow the caliper to slide freely and help prevent dragging brakes do to a stiff slider.
I also apply some antiseize to the hub where it mates to the rotor. Again, I forgot to take a pic of that part, but will next time.
Finally, replace everything. Hook the caliper back on the bottom slider bar and rotate into place. Then tighten down the slider bolts. The torque specs are 28Nm (21 ft-lb). The small screw that holds the rotor is 4Nm (35 in-lb). But that little thing just needs to be snug. It just holds the rotor in place so the holes line up when installing the wheel.
Here is the finished product:
And here is a pic of the new & old rotor. You can see where the inside of the old one only used 2/3 of the friction surface. This rotor would have needed machining to be used again. And as mentioned before, new rotors are quite cheap and only a little more than the cost of machining the old ones. Not to mention the downtime while getting them machined, so just replace them and save yourself time & hassle.
Total time to do each side was around 30 min, but allow yourself an hour and a half to do the job if its your first time. Take your time and enjoy the 'getting your hands dirty' experience while you use the $100 or so you saved to buy something nice for your car /images/graemlins/smile.gif
If I forgot anything or if anyone has any additional tips or want to add anything, feel free to let me know and I will update this thread. Good luck.
PS, I was going to do a 'how to for the rears, but it seems someone has already done one. Here is the link for the one Cosmic did. Good work.
