View Full Version : Master Cylinder bleeding?

07-25-2005, 10:50 PM
Hey guys. I'm changing rotors and pads, and the front-left flex brake line (from wheel well to strut to caliper) which was about to go on me with a good notch in it. :ugh:

I was wondering if, changing the flex line, i need to bleed the master cylinder ? If not, when is it necessary? Only when changing lines all around?

Thanks, will help me learn something new today. :wiggle:

07-25-2005, 11:28 PM
If opening the system up at the brakes themselves, master cylinder bleeding is unnecessary. As far as I can tell, the only time the master cylinder needs to be bled is when you're working on it directly.

Essentially, bleeding only needs to be done in that part of the system below the disconnection. With just a flex line, you can simply use the bleeder screw on the caliper to bleed once everything's connected back up.

07-26-2005, 01:05 AM
That's what i thought, as it's like unplugging the hose on the caliper, but i wanted to make sure. Thanks. :)

BTW, i'm very proud of myself, took 45 minutes to unscrew the damn flex where it connects to the hard line, but didn't lose patience any second. :woot:

That's something to write down on the calendar. :laugh:

07-26-2005, 02:51 AM
Know the feeling, just spent an hour pulling a flex line from a wrecked Celica and the only hard part was the fitting at the hard line.

Kind of irritating, actually. Had no problems with my own car's line, but this thing was so jammed in I finally said to hell with it and snapped the hard line off above the fitting.

Now I can put the line in a vise and use a pair of vice grips on that bloody nut. Doesn't matter if I ruin it, since it was off the donor car and mine's in decent shape.

07-26-2005, 04:07 AM
hehe, i did that to my fuel line (fitting beside fuel tank) when i dropped it and replugged both parts with an 8" fuel line. But for this, i had to be patient, no choice. :yes:

Sucks to have a car that doesn't break too often, stuff has time to jam very well by the time you have to replace. :hehe:

07-28-2005, 03:07 AM
Just a note on this.
To save yourself time and effort, you can do what's called "gravity bleeding".
Loosen the bleed screw and let the brake fluid drain until it drips out of the screw. Make sure you keep the master cyl full tho. :)
Once it drips out of the bleed screw, tighten and bleed as normal.