See page 2 Brake System Bleeding http://web.archive.org/web/201008061...r/checkand.pdf

Here I have the 1994 4runner FSM. To bleed the master cylinder it says to disconnect the brake line, slowly push in the pedal, hold the outlet with your finger then slowly release the pedal. Rinse and repeat 3 to 4 times. Afterwards bleed the system through the bleeder valves at each wheel.

How effective is this method of getting rid of air in the master cylinder? Is it worthwhile to try? And how exactly does it work? Doesn't air just come back into the cylinder once you take your finger off? Wouldn't it be easier to just connect a plastic hose to the outlet and route it back into the reservoir then push the brake pedal until there are no more bubbles? I blew a brake line and pretty sure I got some air in there as the reservoir was nearly empty once I got home and checked what was going on.

 

Unless you have really long arms it is pretty hard to push the pedal and hold the outlet with your finger.

Most use the plastic adapter kits to bench bleed.

If the Master cylinder is on the vehicle I would not remove the lines just bleed at all 4 corners .

Then myself I have not bleed a Master Cylinder when installing in years

 

Tried bleeding at all 4 corners with just myself and a screwdriver and the brakes are still a little spongy. I'll tery again with a helper and if that doesn't fix it I'll look into bleeding the MC some more.

 

you can bleed the master by yourself, just put rags under the joints where the brake line hits the mc, put pressure on the pedal with a long 2x4 that goes from pedal to base of seat, crack the joint momentarily to bleed off pressure, repeat.