My brakes squeal. I can't get them to be quiet. I've replaced the rotors, pads and pad springs, as well as having the calipers rebuilt. I've used the no-squeal stuff for the back of the pads. They never stop making noise, no matter if I'm using them or not. Constant squeal that rarely stops unless the car is completely stopped. Occasionally, the brakes will be completely silent for an entire drive. The next drive, however, "squeak, squeak, squeak."
From what I can tell, it's part of the pad spring rubbing on the rotor. I think there may be something wrong with the alignment between the brake yoke and the rotor. On the outside side of the rotor, there's about 3 times the clearance between yoke and rotor as there is on the inside side (just enough for the pad spring to barely, barely touch the rotor as it spins).
Is there anyone out there with their wheels removed that can tell me if their rotors are "centered" in the yoke? Am I missing washers or something? Is the rotor too thick and needs machining?
My car looks great after hours of buffing the paint, but it's impossible to feel cool when the car screeches/squeaks everywhere it goes.
Brake Squeak
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mbouse
it VERY WELL could be the anti squeal springs bent out of shape and rubbing on the rotor. Take the springs out and see what happens to the noise. short term, your brake effectiveness will not be altered by removal of the springs.
also, i do not mean to sound elementary, or demeaning, but you are absolutely positive it is not the bearings? failing bearings love to make noise only when the car is in motion, even if they appear to be well greased.
also, i do not mean to sound elementary, or demeaning, but you are absolutely positive it is not the bearings? failing bearings love to make noise only when the car is in motion, even if they appear to be well greased.
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So Cal Mark
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manoa matt
- Posts: 3442
- Joined: Thu Oct 26, 2006 4:28 pm
- Your car is a: 1978 Fiat 124 Spider 1800
- Location: Honolulu, Hawaii
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HOLLYWOODSPIDER
Bearings are good.
I replaced the pad springs with new, flat side of the spring toward the rotor, but there's literally 1.5-2mm clearance on the inside side between the yoke and the rotor. There's probably 4mm on the outside side between yoke and rotor. Spacing is the same on both front rotors, which are new.
The springs are causing the squeak, rubbing on the disc.
Will removing the pad springs alltogether cause a catastrophic failure?
Should there be washers between the yoke and the hub to even out the spacing?? Do I have the wrong rotors?
I should also mention that it's the fronts only that are making noise.
I replaced the pad springs with new, flat side of the spring toward the rotor, but there's literally 1.5-2mm clearance on the inside side between the yoke and the rotor. There's probably 4mm on the outside side between yoke and rotor. Spacing is the same on both front rotors, which are new.
The springs are causing the squeak, rubbing on the disc.
Will removing the pad springs alltogether cause a catastrophic failure?
Should there be washers between the yoke and the hub to even out the spacing?? Do I have the wrong rotors?
I should also mention that it's the fronts only that are making noise.
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So Cal Mark
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HOLLYWOODSPIDER
The springs are on in the correct direction. If installed the other way, the arched blades of the springs won't fit between the rotor and yoke on the inside side.
I'm now convinced my problem is in the relationship of the yoke to the disc. I'm going to add some thin washers between the yoke and the hub to even the spacing out and see if that helps. I think that maybe the rotors are cheap and the offset is a mm or two different than the ones I removed.
I'm now convinced my problem is in the relationship of the yoke to the disc. I'm going to add some thin washers between the yoke and the hub to even the spacing out and see if that helps. I think that maybe the rotors are cheap and the offset is a mm or two different than the ones I removed.
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manoa matt
- Posts: 3442
- Joined: Thu Oct 26, 2006 4:28 pm
- Your car is a: 1978 Fiat 124 Spider 1800
- Location: Honolulu, Hawaii
I think your problem is either the springs themselves, or the caliper is not sliding on the yoke.
One thing you need to pay extra special attention to is the small locking blocks, and any surface associated with them. The caliper design is called a floating caliper, which means it is held loosely by the yoke , but is free to move side to side.
When you let off the brake the piston retracts and the caliper centers itself over the rotor. If the locking block, the caliper, or the yoke mating surfaces are rusted or gummed up the caliper won't center itself and you will experience drag or squeek.
When I rebuilt the calipers I not only sanded all mating surfaces, I made shure they were perfectly flat with no burrs on them by using a flat file.
Many times the previous owner will use a screw driver or similar object to drive out the locking blocks. If you strike the edge of the block, you can round over the edge and create a burr. Since the block is steel and the caliper is aluminum the burr will dig into the caliper and the caliper won't move.
Make shure every surface that comes in contact with that block is perfectly flat and smooth as glass. When you reassemble use that green synthetic brake parts lube on all the surfaces including the BACK of the pads.
I just did a complete brake system overhaul and replaced the front rotors. The ones I bought were raybestos brand and were $12 a piece. I think thats the cheepest rotor out there, and they have the exact measurements of the ones I took off.
Its more likely that the new springs you got are wider than the origional, as opposed to a different size rotor.
If all else fails you can use a tin snips to trim the springs a little. I would try that before messing around with shims and washers.
Matt
One thing you need to pay extra special attention to is the small locking blocks, and any surface associated with them. The caliper design is called a floating caliper, which means it is held loosely by the yoke , but is free to move side to side.
When you let off the brake the piston retracts and the caliper centers itself over the rotor. If the locking block, the caliper, or the yoke mating surfaces are rusted or gummed up the caliper won't center itself and you will experience drag or squeek.
When I rebuilt the calipers I not only sanded all mating surfaces, I made shure they were perfectly flat with no burrs on them by using a flat file.
Many times the previous owner will use a screw driver or similar object to drive out the locking blocks. If you strike the edge of the block, you can round over the edge and create a burr. Since the block is steel and the caliper is aluminum the burr will dig into the caliper and the caliper won't move.
Make shure every surface that comes in contact with that block is perfectly flat and smooth as glass. When you reassemble use that green synthetic brake parts lube on all the surfaces including the BACK of the pads.
I just did a complete brake system overhaul and replaced the front rotors. The ones I bought were raybestos brand and were $12 a piece. I think thats the cheepest rotor out there, and they have the exact measurements of the ones I took off.
Its more likely that the new springs you got are wider than the origional, as opposed to a different size rotor.
If all else fails you can use a tin snips to trim the springs a little. I would try that before messing around with shims and washers.
Matt
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manoa matt
- Posts: 3442
- Joined: Thu Oct 26, 2006 4:28 pm
- Your car is a: 1978 Fiat 124 Spider 1800
- Location: Honolulu, Hawaii
Hollywood,
Here are some pictures I took when I took off the calipers for rebuilding.
The relationship of the caliper to yoke was not disturbed, so this is how it would look if installed on the rotor.
http://www.flickr.com/photos/38097470@N00/859605049/
http://www.flickr.com/photos/38097470@N00/859605061/
http://www.flickr.com/photos/38097470@N00/859605107/
hope this helps
Matt
Here are some pictures I took when I took off the calipers for rebuilding.
The relationship of the caliper to yoke was not disturbed, so this is how it would look if installed on the rotor.
http://www.flickr.com/photos/38097470@N00/859605049/
http://www.flickr.com/photos/38097470@N00/859605061/
http://www.flickr.com/photos/38097470@N00/859605107/
hope this helps
Matt
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mbouse
the caliper itself is free (or should be) to slide side to side on that yoke...they are not bound together. the brake pads are free (or should be) to slide in and out on that yoke as well. i see no new scratch marks on the springs. in fact the springs are rusty. metal on metal scratch or squealing noises should produce bare metal marks. everything i see is surface rusty....except possibly the front half of the yoke in picture #107. are those recent scratch marks?
you put on new rotors AND THEN this occured? is that correct? are you 100% positive that the rotors have fully seated on the hubs? if your theory of rotors not centered in the yoke is correct, then the rotors could be not fully placed on the hubs. there should be zero clearance between the inside of the rotor and the face of the hubs.
yoke placement is absolute, firmed up in one exact location with the 17mm hex head bolts. caliper and pad placement is floating, but relative to the yoke. centering the caliper in the yoke is a good place to start. that the piston is out far enough to allow the pads to accept the rotor is good enough. they will self align.
rotor placement should be absolute, but i have personally experienced recently a rotor that did not go on all the way on the hub. i did not discover this until the wheel locating pins would not thread on properly. clean the hub, especially the outside diameter and the face surfaces that contact the rotor. then reset the rotor fully. i used my lug bolts to fully seat the rotor before i installed the yoke.
send me an email if this does not make sense. i really think this is your problem.
you put on new rotors AND THEN this occured? is that correct? are you 100% positive that the rotors have fully seated on the hubs? if your theory of rotors not centered in the yoke is correct, then the rotors could be not fully placed on the hubs. there should be zero clearance between the inside of the rotor and the face of the hubs.
yoke placement is absolute, firmed up in one exact location with the 17mm hex head bolts. caliper and pad placement is floating, but relative to the yoke. centering the caliper in the yoke is a good place to start. that the piston is out far enough to allow the pads to accept the rotor is good enough. they will self align.
rotor placement should be absolute, but i have personally experienced recently a rotor that did not go on all the way on the hub. i did not discover this until the wheel locating pins would not thread on properly. clean the hub, especially the outside diameter and the face surfaces that contact the rotor. then reset the rotor fully. i used my lug bolts to fully seat the rotor before i installed the yoke.
send me an email if this does not make sense. i really think this is your problem.
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mbouse
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racydave
I have used brake cleaner on the rotors but I find carb cleaner to be more effective to remove the oil residue from the rotors after making repairs. Its always proper to clean the rotor to hub mating surfaces as any deviation is magnified by the rotor. I do not know which is most correct, but have noticed some opinions not to lube the slider as it is totally exposed to the environment. And there is a special adhesive that some put on the back of the pads to help retain the pad and also lessen pad rattles. I still wonder if the spring retainers are on correctly? Good luck!
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HOLLYWOODSPIDER
I tore it down again today-
The rotor is mounted flat against the hub. It's behind the rotor (engine side of the rotor) that I have too little clearance, which would mean that the rotor is seated too far onto the hub, which we all know isn't possible.
Mike- You're totally right about the yoke placement being absolute. If I shimmed/washered it, it would move closer to the rotor on the side where I actually need it to be farther away.
Matt- I filed down all of the blocks and associated hardware and greased them before reassembly. Nothing seemed to be corroded or mistreated/gouged, but you never know.
I need to check with the guy I got the rotors from and make sure they've got the correct offset. I'm also considering having them machined (even though they're new) to get another mm of clearance on the back side.
For the time being, I sanded and greased the sliding assembly per matt's tips, removed the "inner" pad springs and generously applied Permatex Areosol No-Squeal to the backs of the pads. We'll see how it goes when I test drive in a few minutes.
The rotor is mounted flat against the hub. It's behind the rotor (engine side of the rotor) that I have too little clearance, which would mean that the rotor is seated too far onto the hub, which we all know isn't possible.
Mike- You're totally right about the yoke placement being absolute. If I shimmed/washered it, it would move closer to the rotor on the side where I actually need it to be farther away.
Matt- I filed down all of the blocks and associated hardware and greased them before reassembly. Nothing seemed to be corroded or mistreated/gouged, but you never know.
I need to check with the guy I got the rotors from and make sure they've got the correct offset. I'm also considering having them machined (even though they're new) to get another mm of clearance on the back side.
For the time being, I sanded and greased the sliding assembly per matt's tips, removed the "inner" pad springs and generously applied Permatex Areosol No-Squeal to the backs of the pads. We'll see how it goes when I test drive in a few minutes.
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mbouse
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HOLLYWOODSPIDER
Machining is only $5 per rotor, and I've already got the rotors. That's the most economical option.
During the test drive, the brakes were about 95% silent. The only time they make noise now is at speed, and I can live with that for the time being.
When I tear it down again, I'm going to get the back sides of the discs machined. Then I can re-install the springs and hopefully have no squeal.
Sorry it took me so long to reply after my test drive, but I was getting a neighbor kid arrested for 4 counts of grand theft auto. I was talking to the police for hours.
During the test drive, the brakes were about 95% silent. The only time they make noise now is at speed, and I can live with that for the time being.
When I tear it down again, I'm going to get the back sides of the discs machined. Then I can re-install the springs and hopefully have no squeal.
Sorry it took me so long to reply after my test drive, but I was getting a neighbor kid arrested for 4 counts of grand theft auto. I was talking to the police for hours.