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I’ve replaced front brake discs, after 200 km I checked the brakes and saw that pads do not grab disc interior (back side pads are OK). I’ve attached 2 images showing the actual disc and calliper holder. Lower piston hole has some play in it, see image, could this cause it? Have some spare holders but same thing, same play on lower piston hole. Am I OK if I use it this way? Will it cause me any problems later?
Thanks
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Are you having any issues stopping? Any pulling when you brake?
This may be a sticking caliper due to lack of lubrication on the guide pins (what I think you are calling pistons).
Recommend lubing the guide pins with silicon paste and checking for even and fluid movement of the pins and caliper assembly…..
-Karl
Not to mention where are the pin boots to keep the debris out?
Did you replace the pads also? Just figured I’d ask.
Yeah, my fault not telling that I took it apart for cleaning, boots are in perfect condition. I’ve done the brake disc change after Eric’s youtube video and the brake is fully operational, slide pins were clean and lubricated when I took it off no sticking. Asked a friend to press brakes while car was lifted and I could see the calliper open slightly to the front applying more pressure on exterior of disc. I’m no mechanic but I’m sure this is caused by the guide pins. I’m sure replacing calliper bracket would fix the problem, but no after market parts for car and OEM are very expensive.
No stopping issues, steering wheel vibration gone (previews disc warped), discs and pads are brand new. Everything is working as it should except brake disc front has uneven wear on both sides, passenger side is slightly better (checked the guide pins and there is not so much play in it like on driver side).
If I’m right after some time new pads will shape after disc and will grab the entire exterior, I’d like to know if I use my brakes like this, will it cause me any trouble on the long run.
Something is very wrong.
First take out the brake pads and remount the caliper with the bolts. Verify that you can easily slide the caliper back and forth. Here in the rust belt it is not unusual to have the slide pin holes well filled in with rust. You need to have really clean holes and pins, lubricated with caliper pin grease. And good booties, properly wedged into the mounting holes so they expand as you move the pins in and out.
Or you may have something reversed. I think I once mounted the caliper bracket on the wrong side of the steering knuckle, throwing things wildly out of alignment. I was able to fit one of the brake pads before noticing how far things were off kilter.
[quote=”grg88″ post=74909]Something is very wrong.
First take out the brake pads and remount the caliper with the bolts. Verify that you can easily slide the caliper back and forth. Here in the rust belt it is not unusual to have the slide pin holes well filled in with rust. You need to have really clean holes and pins, lubricated with caliper pin grease. And good booties, properly wedged into the mounting holes so they expand as you move the pins in and out.
Or you may have something reversed. I think I once mounted the caliper bracket on the wrong side of the steering knuckle, throwing things wildly out of alignment. I was able to fit one of the brake pads before noticing how far things were off kilter.[/quote]
Took out the pads and verified calliper sliding, it goes smooth up to boot length. No sign of rust, looks new only a few wear signs on pins.
Did not reverse anything, always take photos and mark parts before disassembly.
Any other ideas?
Judging by your answers it is not safe or not recommended to use brakes with the mentioned problem. Can anyone please confirm that.Oh, sorry, I misread your description of the problem, I thought it was not pressing on one side of the rotor.
If it’s not pressing on the inner part of the rotor, that could be:
(1) Possibly, normal. Some pads do not reach that far in. Also the rotational linear speed is much higher near the outer edges, so there is a lot more grabbing and heat generation out there.
(2) Look at the brake pads, do they show wear or contact marks most of the way to the inner edge? That shows they’re contacting, probably to the correct extent.
(3) Look at the back side of the brake pads. make sure that any stainless steel shim there is properly centered and has the caliper pressing on it evenly from inner to to outer edge. Make sure that there isn’t any excess brake quieting goop. The surfaces should be flat to within a fraction of a millimeter.
And even if they’re not contacting fully, they will, once the pads wear a little bit. Not a huge concern unless you do a lot of long stretches of downhill braking.
[quote=”grg88″ post=75018]
And even if they’re not contacting fully, they will, once the pads wear a little bit. Not a huge concern unless you do a lot of long stretches of downhill braking.[/quote]
Highest peak around here is 100meter so wont be a problem, thanks for helping.
Long ago we drove our VW Rabbit to the top of Pikes Peak, Colorado, about 9,000 feet of climb and descent. About halfway down they had a guy who would feel your front wheels for excessive heating, then he’d wave you to the gift-shop parking lot if he felt your brakes were too hot. ( Or if gift shop sales were lagging, I suspect ).
Nowdays they probably have an infrared thermometer, but same principle.
I also live in a place where there isn’t a 200 foot rise within 400 miles of here, so brakes in absolutely perfect shape are not such a priority. I imagine the brake shop folks in San Francisco are kept pretty busy.
That looks like a normal wear pattern for new brakes especially if you don’t use them hard. Check them again after a thousand or fifteen hundred miles. By then they should be fully seated in.
If you have uneven pad wear the most likely cause is the caliper slides, it could also be the caliper itself. Most times I find that the caliper slides are either stuck or have the wrong lubrication when I see uneven pad wear. They should have silicone paste as lubricant. That said, if you followed the video you should be up to speed on that. This leaves a possible problem with the caliper itself. By the looks of the pics yours might be on the old side. If the seals in the caliper are having issues then it might be time to replace the calipers. I don’t recommend rebuilding them as they normally require hard parts. By the time you got done with your rebuild, you might have been better off buying new calipers. That way you don’t have to worry about putting any work into them. Here’s a video on what’s inside a caliper that you might find useful.
Good luck and keep us posted.
[quote=”EricTheCarGuy” post=75603]By the time you got done with your rebuild, you might have been better off buying new calipers. That way you don’t have to worry about putting any work into them. Here’s a video on what’s inside a caliper that you might find useful.[/quote]
Problem is I could not find new callipers, only one they sell around here come with no brackets as they hold the pin guides it would be no use to buy them. Tried eBay but all I could find were rebuilt callipers. I’ve checked the seal and does not look like it has any problems so my guess is that the slide pin guides are worn out. Others posted that pads will wear in after some time and will grab the entire disc.
Thank you for helping!
Update
Steering wheel shaking is back, checked the callipers, discs and pads all look normal, guide pins are not stuck. This time it shakes only after warmed up, no shaking from cold start. I found new calliper brackets and waiting for a discount before buying them.
I re-watched all brake related videos, trying to figure out what else could cause it.[quote=”EricTheCarGuy” post=75603]By the looks of the pics yours might be on the old side. If the seals in the caliper are having issues then it might be time to replace the calipers. I don’t recommend rebuilding them as they normally require hard parts. By the time you got done with your rebuild, you might have been better off buying new calipers.
Good luck and keep us posted.[/quote]
After I bought new callipers should I also replace the brake hose? No cracks or damage visible on them…
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