Rear break disks wearing unevenly

[pinballdave]

One thing that hasn't been mentioned is that the calipers can get very tight on the slider pins due to corrosion in the holes in the caliper that the rubber sleeve for the slider pins fits, I've had this on both rear calipers on my P1 C70.

If the pins are tight, then pull out the rubber sleeves and clean the corrosion from the caliper. Check the rubber sleeves, and replace if worn. Clean and re-grease the pins with a rubber safe lubricant.

[Clan]

Originally Posted by VolvoRob38

Hi all,

Here again on a new fault finding quest lol

Can anyone tell me why my rear break disks are wearing unevenly (will attach pics).

I took it for the MOT last month and the lad said I just need to tighten my handbreak and take it for a good run (because I dont use it often working from home, today is the first time in 3 weeks its moved. Had to jump start it!)

So I took it for a run 3 weeks ago and kept tweaking the hand break until the noise stopped or lessened considerably anyway. I thought nice, easy job, I'll perfect it next time I go out.

Went out today for the first time since and the metal rubbing noise was back. So went for a drive to charge up my battery and tighten the handbreak some more. The rubbing noise kept reducing, until I hit the break a few times, then it was back. I tightened it to the point I could smell the handbreak burning... Oh ****, over done it!
So slackened it off 3/4 a turn, but the noise wasnt getting any better. Tried loosening the handbreak several turns back to where it was originally and the rubbing noise got considerably less. "Did he say tighten the handbreak or loosen it" lol.

Anyway, even though it seems to be rubbing less, there is still a metal rubbing noise which sounds awful when driving next to parked cars, or anywhere the sound can bounce back at me through my open window, so need to sort it.

As its both rear disks Im wondering if I need a new hand break?

I did change the pads and disks a while ago but had no issues soon after doing that. I did cross thread one of the caliper arm/bracket things, but got my guy at the garage to re-tap it and it was OK. I did wonder if the thread may have given way or something and thats whats causing it to rub, making the caliper not sit straight. But he said that wont be it and the re-tapping would be sound, plus nothing looks like its not sitting right, and its on both sides. So was thinking handbrake.

Any ideas from you awesome lot would be much appreciated.

TIA

its probably the pads sticking in the calliper , pistons don't seize on volvos generaly .
take the pads out and file the rust area where they contact the bracket . the discs are no good now they have not been working properly for a long time. remember that parking brake depends on the pads and discs being in good condition . you don't want the car running away down a hill !

did you know the proper way to apply the handbrake?
You must apply the brake hard with the FOOTBRAKE first and then keep the pressure on whilst you pull up the lever to lock the pads in place.

[VolvoRob38]

Originally Posted by IainG

Hi
Be careful adjusting the handbrake cable. If the callipers are the same as mine with the wind back pistons and self adjuster on the calliper for the handbrake.
If you try to tighten the handbrake cable too much, the levers on the callipers come off the "stops" this then stops the self adjusters working. You then tighten the cable a bit more and it all gets worse.
The 2 levers, one on each calliper, that the hand brake cable operates need to sit on the stops when the handbrake is off, otherwise the adjusters stop working. My handbrake lever is higher than I would like but the self adjusters do work, has just passed the MOT like that.
Be careful with the wind back tool and ensure you rotate the correct way. Some callipers are clockwise and some are anti-clockwise,

Will check that out tomorrow when I get the wheels off. Cheers 👍🏻

[VolvoRob38]

Originally Posted by pinballdave

One thing that hasn't been mentioned is that the calipers can get very tight on the slider pins due to corrosion in the holes in the caliper that the rubber sleeve for the slider pins fits, I've had this on both rear calipers on my P1 C70.

If the pins are tight, then pull out the rubber sleeves and clean the corrosion from the caliper. Check the rubber sleeves, and replace if worn. Clean and re-grease the pins with a rubber safe lubricant.

When I changed the breaks last time I had an absolute nightmare trying to get those pins back through the rubber sleeves. Not sure if it was lack of grease or the wrong grease or if there was an issue with the rubbers, but it was a stress, particularly on one side. Do you know if those rubber sleeves are pretty standard across models? Halfords is my closest car place, wondering if they'd stock something random like that. If its a specific volvo rubber then probably not lol. If I cant replace for tomorrow I make sure I get those rubbers out and give them a good once over. Cheers 👍🏻

[VolvoRob38]

Originally Posted by Clan

its probably the pads sticking in the calliper , pistons don't seize on volvos generaly .
take the pads out and file the rust area where they contact the bracket . the discs are no good now they have not been working properly for a long time. remember that parking brake depends on the pads and discs being in good condition . you don't want the car running away down a hill !

did you know the proper way to apply the handbrake?
You must apply the brake hard with the FOOTBRAKE first and then keep the pressure on whilst you pull up the lever to lock the pads in place.

I didn't know that about applying the handbreak, I'll remember that in future. Luckily Im on the flat, no hills lol. I did give my handbreak a little test yesterday after sickening it off, and it was pretty solid, I couldn't move it. I'll get the wheels off tomorrow if its not raining and have a proper look. Update with some pics 👍🏻

[Willber G]

Brake.
....

[Simmy]

hand brake operation is in the owners manual. think carefully about which info is correct on the fourm . i still think the discs in the pics are well past there best but thats only my opinion stay safe and make good choices .

[pinballdave]

Originally Posted by VolvoRob38

When I changed the breaks last time I had an absolute nightmare trying to get those pins back through the rubber sleeves. Do you know if those rubber sleeves are pretty standard across models? Halfords is my closest car place, wondering if they'd stock something random like that.

I'd be willing to bet that is your problem. The pins should slide in with minimal effort.

I'm not seeing anything on Halfords website when checking with my car's registration (or Eurocarparts), as I'm sure they'd both prefer to sell you a new caliper. But an eBay search for "slider pin kit C30" returns a few results.

On mine the rubbers were fine to reuse once the corrosion had been cleaned from the caliper holes that was causing them to bind on the pins.

[Simmy]

brakes international sell every thing for brakes springs pins pads discs calipers and rebuild kits/ they have a comprehensive on line store good prices too .

[VolvoRob38]

Originally Posted by Willber G

Brake.
....

Cheers 😅😅👍🏻