rear brakes O-Ring

[QuadRacer18]

is there anything around the shop i can use to act as an o-ring for the brake block-off, i tried bleeding the brakes yesterday and the fluid is leaking out the parking brake block-off and i need this fixed for tomorrow and the cycle shop is closed. let me know! thanks!

[stuntman_12]

You blew the small o ring that sits behind the piston. You can go to Advaced auto parts and get the metric o ring kit. You'll find it in there. I'm havin a problem you may be able to help with.

I blew that o ring... so i replaced it and put everything back together, now i can't get ANY pressure build up to the rear brakes. NOTHING!!! so i can't bleed the brakes!!! I need my rear brakes bad and asap!!!