Brakes binding?

[RobertP]

I have to take my X-reg 1.9 diesel in on Monday as the r/h rear brake is coming on 'slowly'. But driving home yesterday (about 30 miles) I got the smell of cooking asbestos. The car drove ok, no warning lights or strange noises, so I thought it might be from outside, but when I got home and checked, the other three discs were too hot to touch. It drove perhaps a little sluggishly, but the brakes certainly weren't hard on. I was advised the brake fluid needs changing this year, but could this have caused it, or am I looking at a new master cylinder? Old cars, eh?

[Clan]

Originally Posted by RobertP

I have to take my X-reg 1.9 diesel in on Monday as the r/h rear brake is coming on 'slowly'. But driving home yesterday (about 30 miles) I got the smell of cooking asbestos. The car drove ok, no warning lights or strange noises, so I thought it might be from outside, but when I got home and checked, the other three discs were too hot to touch. It drove perhaps a little sluggishly, but the brakes certainly weren't hard on. I was advised the brake fluid needs changing this year, but could this have caused it, or am I looking at a new master cylinder? Old cars, eh?

It is common on these for the pads to stick in their holders , take all the pads out and clean the slots where they fit and lightly file the mating edges of the pads so they drop in with no tendency to stick .

[ITSv40]

As Clan has said. Don't just clean up and free the sticking caliper, check the other three as well and make sure everything is free and operating correctly.

I always have the pads out every year just before the MOT is due and clean everything up and lube the sliders etc. It is all part of the routine annual service. My old V40 - 370,000mls - was still on all the original calipers and brakes all still good.

[RobertP]

Thank you. I'll ask them to do that tomorrow, and keep my fingers crossed. I will keep you posted.

[Miketwovolvos]

the pistons in those calipers are threaded, so you have to wind them in to replace the pads...also, dealers even seem to forget the principle that the pads have to float and I have seen them hammered in and stuck...As somebody said above, lubricate the edges of the pads where they meet the calliper...I use copper ease which seems to work well. Also, the handbrake mechanisms sticks on those callipers also..it corrodes so dismantle it and clean everything up (don't lose the spring) and check that the handbrake fully releases. If the handbrake binds on one side, you will get the brakes jamming on and it eats your pads and overheats and can warp the disk.

It is an ingenious system though, designed so if you have a rear disk set up, you don't need a separate drum-type system for the handbrake built into the hub/disk assembly like in the old 700/900s, the threaded piston is operated by the main hydraulic (footbrake) as well as the mechanical handbrake.

[canis]

I have recently discovered it is also possible for the handbrake cable to become corroded, worn and frayed internally. This makes it's retraction difficult, holding the caliper on. It's possible the caliper is not at fault at all. You need to check the cable can slide freely through it's sheeth without struggle.

[pierremcalpine]

Originally Posted by canis

I have recently discovered it is also possible for the handbrake cable to become corroded, worn and frayed internally. This makes it's retraction difficult, holding the caliper on. It's possible the caliper is not at fault at all. You need to check the cable can slide freely through it's sheeth without struggle.

I too have discovered the same thing.

Further to the feedback from others - make sure that you lubricate the two slider pins for each caliper when you (or the mechanic) are in there!!!

[RobertP]

Thanks to all for your advice. The garage have cleaned and greased both rear brakes. I now have a 13-month MoT (there were a few other issues). I will pay attention to the brakes, and service the front ones if the problem recurs. It's driving normally now.