Brake pad worn all the way and Caliper sticking

turbowagon1776 · Post by **turbowagon1776** » 18 Aug 2011, 12:10

Hello everyone I am new here. I am the owner of a 1993 volvo 940 turbo wagon and this is my first question.

On my back left tire I had the outside brake pad worn down all the way and the inside still had half the pad left. The rotor was scratched up pretty bad on the outside from the pad being worn down to where I had to go get it turned at a shop.
I went and bought new brake pads and was trying to replace them this morning and I tried to insert the new ones in the caliper but they would not fit, like they had too much pad on them when I noticed the pistons were not all the way back in the caliper so I get in the car and started it up and watched the pistons as I applied pressure to the brake. The piston on the outside side did not move at all while the inside one went out, but as I let go of the brake the piston did not go back in. So I kept pressing on it hoping to break it free when the inside one popped out all the way and started pouring brake fluid everywhere. So I have one piston that wont do anything and the other piston is out of the caliper now and wont go back in.

I know nothing about brakes honestly and I was trying to put the piston back in the caliper but it wont go back in. I notice all the gaskets and seals are dried and cracking apart but it was never leaking brake fluid.

Can calipers be fixed? What would cause it to behave like this and what should I do? any help would be greatly appreciated.

Post by **billofdurham** » 18 Aug 2011, 12:47

Welcome to Matthew's Volvo Site.

One of the pistons in the calliper has seized, probably due to rust because of a bad or damaged seal. As it did not retract that pad was left binding on the disc subjecting it to rapid wear. This is common on cars that have not been serviced properly.

As you say you know nothing about brakes I shall try to give you some pointers:
1. When the brake pads are removed from the calliper never press the brake pedal as you will end up with one or more pistons on the floor, as you have seen.
2. If the seals are dried and cracking, and a piston is seized, the calliper is at the end of its useful life and needs to be replaced.
3. With this problem on this calliper you need to check the others as they may be in the same, or worse, condition.
4. Callipers can be rebuilt but by your description I would think that this would not be possible in this case.

Check the others to see if you need more than one. You will find site sponsors' ads at the top of the forum. They all sell Volvo parts way below dealer prices. If you do order from them please mention this site.

When you have the necessary parts let us know so we can take you through the procedure for replacing the calliper(s), pads and bleeding the brake system to get rid of the air that you have introduced into the system.

Bill.

turbowagon1776 · Post by **turbowagon1776** » 23 Aug 2011, 09:25

Ok been waiting on the caliper forever to arrive from the parts store. I went to go take off the old caliper and could not remove the brake line at all the screws were so tight I had to just cut the line and order the new brake line. Problem is, I still cant get the other bolt off from the main metal brake line. So any hints on getting bolts off please feel free to drop lol.

now I must put the new caliper and line on along with the new pads. I was reading somewhere that older cars you may not be able to bleed the brakes because they have some kinda seals or valves, Is this the case with the 940? any advice would be a world of help!

turbowagon1776 · Post by **turbowagon1776** » 23 Aug 2011, 09:39

other quick question. Must I bleed all the brake lines now? and must I replace both brake pads for the driver and passenger side now? is there a tutorial somewhere for this stuff lol? I have only bleed brakes once in my life many years ago on a chevy 1500.

turbowagon1776 · Post by **turbowagon1776** » 23 Aug 2011, 22:53

got it all fixed, had to cut back on the brake line some but pretty cheap to fix, pretty big pain. Now im trying to get the bolt off the oil pan. err every bolt on these old cars are seized!

scorpiodad78 · Post by **scorpiodad78** » 10 Sep 2011, 01:15

I have a 1993 940 turbo sedan and let me tell youI feel your pain brother, I replaced waterpump, changed the oil, rotated my tires , changed some hoses, mass air flow censor , other minor odds and ends that shouldn't be a big deal but is because all the bolts are seized and I'm looking to change the brakes now . The guy that had this car before me did nothing but gas her and trash her. I love this car for some reason and I'll do what ever takes to keep her on the road but man, I could choke the previous owner.