Replaced a rear wheel bearing last month. While re-assembling the rear brake drum I had to squeeze the shoes to get it back on. The brakes had expanded a little while sitting. While I was squeezing the shoes they all of the sudden gave way and they collapsed all the way. I could hear a rush of fluid to the front. I assumed I fractured a line somewhere or a joint. No leaks anywhere. The problem is I now have no brakes. The pedal goes straight to the floor. I can pump and build up a small amount of pressure but it fades with in seconds. The brakes were solid on this car before hand. Previous owner did all new lines, and cylinders last spring. Did I ruin my master cylinder? Thanks in advance guys for any input.
Not yet. I don't understand how there could be air in the system now because I never removed or opened any brake components. I will try to bleed them tonight. Thanks guys.
If the rear wheel cylinder extended too far (which it sounds like it did) then it could have gotten air in it there.
Would the air also been the reason I was able to squeeze the shoes together and collapse the rear cylinder with the master cylinder still sealed?
There is a return port in the master cylinder, so it will allow fluid to enter the reservoir from the lines, when the pedal is not pressed
Yes because air compresses and fluid doesn't. If you try and bleed the brakes and find your not able to and there are no leaks, the master cylinder is blown. It would not have been from anything you did just that it was it's time and you should be very glad it didn't happen on the road. Sent via Illinois Bell Telephone Company's Car Radiotelephone
You may have manhandled the shoes a bit and popped a wheel cylinder piston out. Most of the escaping fluid may be within the rubber boot, but take the drum off and give it a good look. I find brake fluid leaks better at night. Just crawl under the car a bit and shine a flashlight on the suspect areas. On the back of the wheels/backing plates, follow the brake lines down the chassis, etc. Bob
All good advice there,,,you can get spring clips, sort'a like pliers to hold cylinders while working brakes and such,,,
Got the brakes fixed. Turns out it was the check valve in the master. It had a huge tear in it. Rebuilt and reinstalled and the car stops straight and true now. Thanks guys!