Brake repair tips with pics
04-28-2006, 06:38 AM
#1
Brake repair tips with pics
Frank's writeup on brake repair is fantastic and very detailed. http://www.motorvate.ca/mvp.php/300
I'd like to add to his notes and help others prevent making the same stupid newbie mistakes I did.
Summary – For years every spring I visually inspected my rotors and pads not really knowing how they worked. Going forward I will also now inspect & lube my caliper pistons, caliper sliding pins, and boots covering same. This will probably take no more than 90min for all 4 corners every year and will save hundreds in parts and prevent future braking problems. Between Haynes, the .org, and other sources here’s a few tips I learned as a brake newbie.
It started after this winter when I got a severe vibration when braking. I first inspected the rear brakes and they looked ok. Then I found the below on the fronts. One caliper sliding pin was rusted and another’s boot was dried out preventing movement of the caliper. Both inner rotors had irregular wear and fused pad buildup.
DO NOT – assume which brakes are at fault
DO – try the ebrake to verify the braking problem is in back vs front and save some time
I did Dremmel out the slots in one rotor (hack job) but the vibration continued. Decided to replace rather than bother with recutting the rotor since they were 4 years old anyway. I bought rebuilt calipers for the fronts but it turns out they just needed some lubing and working the piston in & out and I never needed the new ones. Brush brake fluid on the piston boot/seal and clean out as much dirt as possible. Extend the piston out by pressing down on the brake pedal (all lines connected). Wire brush the exposed piston as clean as possible w/o damaging the boot around it. Lubricate with more brake fluid and press back in the bore with C-clamp/wood etc. Work it in & out a few times. Lube the caliper pin boots with WD40 or similar and soften them back up. Of course caliper grease inside the pins.
DO NOT – assume the caliper pistons are bad
DO – try cleaning them and the pins first to get everything “floating” again
Getting my rotors off was no easy task. 50K miles, 4 winters, and 4 hot summers of racing rusted these things to the hub. I started with liberal amounts of liquid wrench and a 20oz hammer with no luck. I thought hammering on the wheelstuds might help not realizing they didn’t hold it on at all. Made me feel better though. I did try the 10mm bolts into the rotor too but snapped one off working it in. I did clean the hole first and applied anti-sieze too but it still snapped. The other bolt snapped right after that while I was trying to back it out carefully. Finally I resorted to using the back of an axe to break it off the hub.
Back to the studs. Now 2 of my studs were damaged and nuts couldn’t be threaded on. The correct way to hammer out studs is to thread a nut on first, then hammer on that. (Right pic above). If you couldn’t tell, my studs are 60mm long and you can’t just go to the dealer and get more. I didn’t want to pay Nismo’s price either so I called H&R. Turns out you can special order any of their longer studs through their dealers for like $5 ea. incl ship. I was driving around for a week on only 3 lugs on one wheel with the 2 loose studs ziptied in place. (kids don’t try at home)
DO NOT – hammer out studs directly
DO – thread lugnut onto end and line up with end of stud to spread the force
DO NOT – use any cheapo bolt to thread into the rotor
DO – try and find the hardest grade bolt that’ll stand up to the torque
After all was together again and bedding my front pads I realized my rear calipers were also in serious need of maintenance. The rear rotors got to 450degL, 550degR which was hotter than the fronts at 350ish.
Other suggestions - keep calipers attached to the brake lines as long as possible. Even with the $1.49 “HELP” brake hose plugs from Autozone I couldn’t stop the fluid completely from coming out the banjo bolt. While completely disassembling a front piston I probably lost a pint or more of fluid. Make sure you got plenty extra before starting any brake work if this is your only vehicle. Also, do rent the caliper repair kit for turning the rear calipers as needlenose pliers couldn’t budge mine. Finally some plastic hose and Speed Bleeders did make short work of bleeding the lines. Heck, that only took minutes compared to the hours of other time spent.
I’m glad I got so hands on with the braking system as it is the most important part of the vehicle
I'd like to add to his notes and help others prevent making the same stupid newbie mistakes I did.
Summary – For years every spring I visually inspected my rotors and pads not really knowing how they worked. Going forward I will also now inspect & lube my caliper pistons, caliper sliding pins, and boots covering same. This will probably take no more than 90min for all 4 corners every year and will save hundreds in parts and prevent future braking problems. Between Haynes, the .org, and other sources here’s a few tips I learned as a brake newbie.
It started after this winter when I got a severe vibration when braking. I first inspected the rear brakes and they looked ok. Then I found the below on the fronts. One caliper sliding pin was rusted and another’s boot was dried out preventing movement of the caliper. Both inner rotors had irregular wear and fused pad buildup.
DO NOT – assume which brakes are at fault
DO – try the ebrake to verify the braking problem is in back vs front and save some time
I did Dremmel out the slots in one rotor (hack job) but the vibration continued. Decided to replace rather than bother with recutting the rotor since they were 4 years old anyway. I bought rebuilt calipers for the fronts but it turns out they just needed some lubing and working the piston in & out and I never needed the new ones. Brush brake fluid on the piston boot/seal and clean out as much dirt as possible. Extend the piston out by pressing down on the brake pedal (all lines connected). Wire brush the exposed piston as clean as possible w/o damaging the boot around it. Lubricate with more brake fluid and press back in the bore with C-clamp/wood etc. Work it in & out a few times. Lube the caliper pin boots with WD40 or similar and soften them back up. Of course caliper grease inside the pins.
DO NOT – assume the caliper pistons are bad
DO – try cleaning them and the pins first to get everything “floating” again
Getting my rotors off was no easy task. 50K miles, 4 winters, and 4 hot summers of racing rusted these things to the hub. I started with liberal amounts of liquid wrench and a 20oz hammer with no luck. I thought hammering on the wheelstuds might help not realizing they didn’t hold it on at all. Made me feel better though. I did try the 10mm bolts into the rotor too but snapped one off working it in. I did clean the hole first and applied anti-sieze too but it still snapped. The other bolt snapped right after that while I was trying to back it out carefully. Finally I resorted to using the back of an axe to break it off the hub.
Back to the studs. Now 2 of my studs were damaged and nuts couldn’t be threaded on. The correct way to hammer out studs is to thread a nut on first, then hammer on that. (Right pic above). If you couldn’t tell, my studs are 60mm long and you can’t just go to the dealer and get more. I didn’t want to pay Nismo’s price either so I called H&R. Turns out you can special order any of their longer studs through their dealers for like $5 ea. incl ship. I was driving around for a week on only 3 lugs on one wheel with the 2 loose studs ziptied in place. (kids don’t try at home)
DO NOT – hammer out studs directly
DO – thread lugnut onto end and line up with end of stud to spread the force
DO NOT – use any cheapo bolt to thread into the rotor
DO – try and find the hardest grade bolt that’ll stand up to the torque
After all was together again and bedding my front pads I realized my rear calipers were also in serious need of maintenance. The rear rotors got to 450degL, 550degR which was hotter than the fronts at 350ish.
Other suggestions - keep calipers attached to the brake lines as long as possible. Even with the $1.49 “HELP” brake hose plugs from Autozone I couldn’t stop the fluid completely from coming out the banjo bolt. While completely disassembling a front piston I probably lost a pint or more of fluid. Make sure you got plenty extra before starting any brake work if this is your only vehicle. Also, do rent the caliper repair kit for turning the rear calipers as needlenose pliers couldn’t budge mine. Finally some plastic hose and Speed Bleeders did make short work of bleeding the lines. Heck, that only took minutes compared to the hours of other time spent.
I’m glad I got so hands on with the braking system as it is the most important part of the vehicle
04-28-2006, 07:31 AM
#3
how did u get the temps for the rotors?
An interesting note... if you disconnect the brake line, a bubble can enter and fluid will leak. I found that unscrewing the brake fluid reservor cap stops this from happening. Gravity takes over (very slowly) and you don't lose much fluid if you swap out the calipers pretty quick. Since fluid is very slowly moving down, there's less chance of a bubbling travelling up your line.
Jae
An interesting note... if you disconnect the brake line, a bubble can enter and fluid will leak. I found that unscrewing the brake fluid reservor cap stops this from happening. Gravity takes over (very slowly) and you don't lose much fluid if you swap out the calipers pretty quick. Since fluid is very slowly moving down, there's less chance of a bubbling travelling up your line.
Jae
04-28-2006, 08:40 AM
#4
Maintaining the calipers is key, they commonly seize up when they are not maintained properly and can cause big problems. Good suggestions keeping the calipers greased will make them perform better and last longer.
04-28-2006, 11:08 AM
#6
Nice job on this post. Can hopefully be transferred to DIY post. The only question I have is that my driver side roter is rust and where the bolts go to pop out the roter is gone (no more threads rusted), so what can I do about that?
04-28-2006, 07:17 PM
#7
Joe, I happen to carry around an infared pyrometer for fun.
Chris, guess my studs were really rusted in place as it multiple hard wacks to budge em.
Toshi, sounds familar. If you can't thread bolts in there then just spray PB or similar on both sides between the rotor and hub and start banging away. If you know you're replacing the rotor then feel free to bang on the outer edges with the heaviest hammer you got and keep spinning the rotor around evenly as you go. I really think a 2lb+ or slege from the backside worked great. See you around - I'm the one downshifting everywhere not using the brakes lately.
Chris, guess my studs were really rusted in place as it multiple hard wacks to budge em.
Toshi, sounds familar. If you can't thread bolts in there then just spray PB or similar on both sides between the rotor and hub and start banging away. If you know you're replacing the rotor then feel free to bang on the outer edges with the heaviest hammer you got and keep spinning the rotor around evenly as you go. I really think a 2lb+ or slege from the backside worked great. See you around - I'm the one downshifting everywhere not using the brakes lately.
04-28-2006, 08:48 PM
#9
I just changed my own brakes, for the first time, and i noticed the front 2 rotors are lose, they can shake back and forth. Are they supposed to be like that? Also when i was putting on my summer rims i noticed that one of the back calipers is frozen, because the brake pad is lightlys on the rotor at all times, the wheel can still move but slower than the other wheel. I wasnt able to unscrew the two bolts so i can open the caliper, anyone have suggestions how i can loosen those bolts?
04-29-2006, 05:35 AM
#12
Martin, spray a little PB or penetrating lube on those pin bolts and try a bit more leverage. They're only supposed to be on there with like 20 ftlbs of tq so they shouldn't be too tough. (Similar on the bigger caliper bracket bolts)
Jae, yes, you're right. Not documented above but I did wire brush every bolt, lock washer, and surface I could before using 1600deg copper anti-sieze compound on the hub, lug stud head area, etc and regular anti-sieze on bracket and pin bolts.
Jae, yes, you're right. Not documented above but I did wire brush every bolt, lock washer, and surface I could before using 1600deg copper anti-sieze compound on the hub, lug stud head area, etc and regular anti-sieze on bracket and pin bolts.
04-29-2006, 09:49 AM
#13
Originally Posted by BEJAY1
Jae, yes, you're right. Not documented above but I did wire brush every bolt, lock washer, and surface I could before using 1600deg copper anti-sieze compound on the hub, lug stud head area, etc and regular anti-sieze on bracket and pin bolts.
Jae
05-01-2006, 05:18 AM
#14
rear caliper update
As mentioned my rear rotors were dragging more than I thought they should. Cleaning those calipers didn't help as the internal spring or piston seemed to be binding (needlenose pliers couldn't turn the piston much at all). I would spin either wheel and it would stop after only 1.5 to 2 revolutions (ebrake disconnected).
I then replaced the passenger caliper. Wheel now spins about 3-4 revolutions in comparison (heavy wheels). Light braking around town resulted in rotor temps of 70ish deg vs 90ish on the opposite non-repaired side in 55deg weather. Think I'm gonna replace that other caliper for the heck of it too.
Edit - more brake bedding Mon showed front temps of 325ish, LR 260, RR 340. So just lubing and cleaning one caliper brought that rear temp down about 15%, and repairing the other down over 40%.
I then replaced the passenger caliper. Wheel now spins about 3-4 revolutions in comparison (heavy wheels). Light braking around town resulted in rotor temps of 70ish deg vs 90ish on the opposite non-repaired side in 55deg weather. Think I'm gonna replace that other caliper for the heck of it too.
Edit - more brake bedding Mon showed front temps of 325ish, LR 260, RR 340. So just lubing and cleaning one caliper brought that rear temp down about 15%, and repairing the other down over 40%.
05-02-2006, 01:03 AM
#15
Senior Member
Join Date: Jul 2004
Posts: 888
how can u tell that the brakes are locking up on the rear? i mean sticking.
when i got it up and changed, (with ebrake down) i was able to spin freely, no drag. do u mean ur 3-4 revolutions stopped or something? shouldn't it spin freely infinately ?
when i got it up and changed, (with ebrake down) i was able to spin freely, no drag. do u mean ur 3-4 revolutions stopped or something? shouldn't it spin freely infinately ?
05-03-2006, 04:43 AM
#16
Not only have the ebrake down, but disconnect it at the caliper entirely to free up the spring. Spin the wheel a certain speed to see how long it takes to stop with the pads gently dragging on the rotor. Now pivot the caliper out of the way and spin again w/o the pads. There shouldn't be much difference otherwise the pads might be creating too much drag.
If the wheel still doesn't spin much at this point it could be worn wheel bearings. The wheel won't spin infinately due to friction in the wheel bearings.
If the wheel still doesn't spin much at this point it could be worn wheel bearings. The wheel won't spin infinately due to friction in the wheel bearings.
05-03-2006, 05:33 AM
#17
Member
Join Date: Dec 2004
Posts: 36
Thanks for the info. Can someone anwser this? I have no experience on repairing brakes. I have had the rear driver's caliper replaced because of leaking brake fluid. The rear passenger caliper was replaced almost two years ago because of a sticking caliper pin that had gone bad. Well on the first time the rear passenger caliper was replaced, I noticed excessive brake dust only on the rear passenger wheel. The other 3 wheels's dust looked normal. Only the rear passenger. I don't remember what I did after that if I had them adjusted or what but now my rear driver's caliper is dragging constantly on the wheel causing excessive brake dust. When I come to a stop or in stop on go traffic, I can hear the rear driver's brake making a noise like the caliper is engaging. What do I do? I am pretty handy with repairs to my car but I haven't tackled on the brakes yet. Should I take the car back to the shop to have it adjusted so the driver's rear won't drag or have the rear passenger caliper replaced again so they could be even?
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