Brake Master Cylinder

[dhump4free]

This weekend I was prepping my car for a little mountain road trip and had to change the brake pads among some other items. After changing the front pads, I got back in the car to pump some pressure back into the brakes and the first pump went all the way to the floor. Now every time I push on the brake it goes very close tot he floor before engaging and stopping the car. If I give little pumps the pressure builds up and and the brakes engage around halfway, but when I release the pedal it becomes soft again.

I've been doing some research and everything seems to be pointing towards me blowing the seals on the master cylinder. Has anyone ever experienced this while changing brake pads or flushing brake fluid? How about installing a new master cylinder? Any advice or guidance is appreciated.

[billr99]

Make sure you have your pad anti-rattle springs in properly. If they aren't done up right you won't get any pedal.

For reference (http://www.volvoxc.com/0/resources/how-to/pdf/xc_front_brake_pad_replacement.pdf) but also do a search on this forum for an actual picture of the springs in their proper position. Unfortunately I can't find one at the moment but this is a fairly common issue especially for those doing this type of pad/caliper design for the first time.

Cheers,

Bill

[Antherzoll]

I'd check your fluid level and get the lines bled before changing the brake booster. Could be you pushed up some fluid and now it's low.

From the resources section, if you scroll to the last pages there is a test for the brake booster.

http://www.volvoxc.com/0/resources/how-to/pdf/power-brake-booster-replacing.pdf

[dhump4free]

Make sure you have your pad anti-rattle springs in properly. If they aren't done up right you won't get any pedal.

For reference (http://www.volvoxc.com/0/resources/how-to/pdf/xc_front_brake_pad_replacement.pdf) but also do a search on this forum for an actual picture of the springs in their proper position. Unfortunately I can't find one at the moment but this is a fairly common issue especially for those doing this type of pad/caliper design for the first time.

Cheers,

Bill

Thanks Bill, I when I was putting the anti-rattle springs on I modeled them after the other side of the car. Just to be sure we are talking about the front caliper springs right(http://www.ipdusa.com/products/4746/114274-front-brake-caliper-spring-s60-v70-s80-xc70?

[dhump4free]

I'd check your fluid level and get the lines bled before changing the brake booster. Could be you pushed up some fluid and now it's low.

From the resources section, if you scroll to the last pages there is a test for the brake booster.

http://www.volvoxc.com/0/resources/how-to/pdf/power-brake-booster-replacing.pdf

Fluid level is normal, however I just received the parts from Motive to do bleed and flush the brake lines. I'm hoping that putting some new fluid in there will fix the problem before I go spending a lot of money trying to fix the MC.