Hey all,

As some of you have seen, I'm replacing the brake hydraulic system on a '93 F-150 (2wd, 4.9 I6). I have bench bled the master, but since then I've installed most of the new brake lines, including the fittings into the master, but still have to finish the front L to R brake line and replace all the hoses. I've attached the lines to the master, but there's still plenty of bleeding to do at the wheels, so do I need to re-bleed the master as well? Or do I only need to bleed the master if I have let the reservoir run dry and had air run through it? I'm thinking it's the latter, and that I don't need to do anything else with the master as long as I keep it topped up.

Secondly, it is possible to bleed the master while installed, right? I don't have the Haynes manual in front of me, but I'm pretty sure it says you can loosen the fittings and pump the brake as you would bleed at the wheels, then tighten the fittings, release the brake, and boom, bled Does that sound right?

Thanks again!

 

If you have bench bled the master properly, then you shouldn't need to bleed it again unless you let it run dry while bleeding the lines. Just keep it well topped off while bleeding and you should be fine.