Bleeding brakes with a dry MC?

[Moebius]

I've swapped over struts and a diff in my ae71 and didn't crimp the lines or anything, so the brake fluid has drained out of the master cylinder. After refilling with fluid, I can't get any pressure in the system, the brake pedal will not firm up, so I can't bleed the air from the lines. I did a bit of googling and people seem to recommend something called "bench bleeding", but I can't get my head around the process.

Is this my problem and will I have to do this bench bleeding? If so can someone please explain the process?

[julzy]

Crack all the bleeding nipples open,
and fill the master up with fluid.
Put a bucket under each corner and just wait for it to bleed through.
If it doesnt slowly pump the pedal a few times,
just keep topping up the master

[Simon-KE70]

its easy and all you need is a One Man bleed kit... or basically a bottle/jar with 1/4 brake fluid in it, and some hose which will fit on the bleed nipple.

fill the MC, start with the rear left master and crack the nipple, fit the hose and make sure the end is submerged in the fluid in the jar.

pump the peddle slowly and dont use the full travel of the peddle, reason for this is under normal braking conditions the piston does not go the whole length of the bore, so the potnetial is for the seals to get damaged when traveling in territory they dont normally see.

so yes... keep pumping til the jar starts rising in fluid level, then close the nipple and go to rear right, same process... keep going til fluid rises in the jar again (mark the jar if it helps and keep an eye on the MC fluid level)

then do front left and front right.

SHOULD be spot on once this is all done., if not then you have a problem or didnt do it right.

[Moebius]

Opened all the bleed nipples up and a little bit came out of the front right and then stopped, the rest are bone dry.

When you remove the reservoir from the MC and look down the hole, should you see the piston move when you pump the brake pedal?

[Simon-KE70]

what do u think forces the fluid against the caliper pistons?

of course its suppose to move.

do it the way i suggested.

[Moebius]

Right, well that's what I thought, but it wasn't moving so I wanted to be sure it was fucked before I remove the MC.

I did try bleeding them normally first but didn't get anywhere, I guess due to the fact that the piston wasn't moving.

[Simon-KE70]

the piston is a mechanical linkage to the peddle itself, the peddle has a pushrod pushing into the booster and then out onto the master. unbolt the master from the booster and leave all the lines on for now, then get a mate to slowly push the brake peddle and see that the push rod comes out.

[Moebius]

Will do, thanks for the help.

[slydar]

dont know if all thats necessary. just crack the lines at the master first, get some fluid there. then at the junction. once youve got some there, you should be able to just pump some fluid through.

[markiitourerv]

Yes, do that - crack all the lines on the master and pump the pedal til fluid comes out of the tube nuts on the master cylinder, then do them up, and bleed the rest of the brakes starting at the LHR.

Shouldn't be much more complicated than that.