How do I avoid an ABS bleed?

[xxxwhyzee]

Is there a way to swap master cylinder/vac booster w/o getting air in the HCU?

I have a 93 Sport 2wd with 4w ABS. The brakes work great, but the MC has a slow leak (light comes on and I top it off every 2-3 months). The vacuum booster has missing paint and some rust right below the MC attach point, so the leak seems to be coming from there. I want to change out both parts before the problem gets worse, but I do not want to deal with trying to have the ABS unit bled. After reading this forum I know it requires a special tool that most dealers don't have and can't get any more. There is one on eBay, but it is like $400 for the tool and wiring adapter.

So my question is; Is there a way or technique to replace the master cylinder without getting air in the ABS unit, so it will not have to be bled?

 

[FR-425]

The trick to bleeding ABS is to get the valve to trigger.

Here's my trick:

I have a spare rotor that I have broken off a couple of the signal vanes. (see image)

Install this busted rotor temporarily, and drive the vehicle "slowly" around the block applying light pedal. (doesn't matter which side)

Each time the gap passes the pick-up, the ABS valve will pulse.

You'll hear it, clunk, clunk, clunk.

20- 30 clunks does the deed, to get the air past the ABS block.

Then bleed as normal.

Install your good rotor and your Done!

 

[vroomzoomboom]

i dont know if this is the same or not, but i once had to do a brake line on my sisters 06 escape (the line blew out when she was stopped and waiting for someone thankfully). all i did was bleed the brakes, then found a grass field, ran it up to speed and hammered on the brakes to make the ABS pump kick on a few times then went home and rebleed the brakes again. it did work, but i dont know if thats the same for your problem or not.

 

[jd4242]

I would think if you avoid spilling fluid out the lines and bench bleed the mc you could vacuum bleed it from the reservoir.as long as you dont force air downwards into the hcu.if not being 2wd you should be able to securely jack the rear up on stands and put it in gear with the front still on ground.hit the brakes a couple times, it will think the front are locked up, which they are because they are not spinning.this will engage abs.

OBVIOUSLY SECURE THE VEHICLE GOOD, NO-ONE OR ANYTHING IN FRONT OF YOU..my disclaimer

 

[xxxwhyzee]

Thank you guys. It seems like all good advice. I was hoping for a way to avoid getting air in the lines when I disconnect the MC, but I don't see how that could happen. Even if I plug the lines as soon as I disconnect them, at least a little air would have to get in there.
So on to option 2; How to bleed the ABS module. If activating the ABS a few times is all it takes to move the air bubbles past it, that's not so bad. I don't have a spare rotor or an open field I can tear up and skid through, so I think I'll try the "jack up the back" method.
It may be a couple of weeks till I get to it, but I will keep you posted on the results.