Hi Guys,

I changed front and rear calipers and brake hoses and unfortunately I let the master cylinder get empty.

I have a power bleeder and I understand the normal order is: right rear, left rear, right front, left front. However, before I do that, what other steps do I need to take? Do I need to bleed the master cylinder first? Has anyone had to do this before?

I think the issue is getting the air out of the ABS unit. And you need a diagnostic tool to do it.

You should have locked the pipes off with a clamp

You "can" wreck the master cylinder and the ABS pump with a pressure bleeder, think I'd have a go at filling up the master cylinder and opening the caliper bleed screws and seeing if you could get it through by gravity, worse ways a vacuum pump on each nipple (shut the other three) and very gently pull a vacuum....

Good luck... Pete

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As quick as assisted bleeders are, I think you often get too much fluid left in the master tank which you need to take back out. A 2 person job I think is easier, cleaner and just as quick.

As for bleeding the abs, wouldn't be the first time I've ragged it along some gravel and slammed the brakes on to kick in the abs system to flush it through  V8 or else ...

As it turns out, the master cylinder was not completely empty. The following morning I took the cap off and looked directly down and tapped on the master cylinder. I could see the fluid moving back and fourth. It was very low, but definitely not empty. Do you think I am ok? Or is it still bad if it is very low?

Fisha, could the same be achieved by engaging HDC and going down a few levels in a parking garage? I like where your head is at, outside the box

If the master cylinder isn't fully empty fill it with new fluid and leave it to stand overnight to let any bubbles to come to the top. I'd then be inclined to take Petes ( Haylands) advice and bleed the new fluid in initially by opening one bleed screw at a time and letting gravity do the work. It doesn't take long for the fluid to come through, changed the fluid on my brakes recently doing this.
See what result you get then possibly finally bleed the brakes the old fashioned way... two people.
With a bit of luck you may not get any air into the abs, if you do take fishas advice...it works.

HDC would work as well. I've done that too  V8 or else ...