05 Trail blazer brake issue

[MuleShack]

I'm helping a friend out and doing her front brakes for her. all went as normal replacing rotors and pads. Got everything put back together and bled the lines and I cant get any pressure to the calipers. I had her pushing the pedal down while I worked the bleeders and it would spit some air out and then just trickle one or two drops on each push of the pedal.

With my dodges, even with an empty caliper resevoir it would only take about 3 pedal pushes to get pressure and spit out of the bleeder. We have been cycling thru each side about 15 times and it doesn't improve.

It sounds like the master cylinder is whiffing. The brake fluid resevoir is full.

The only anomoly was the battery died while I had the key turned on, so the clock reset on the radio etc. would this cause the brakes to not work properly.

Is there something else on a chevy (All Dodge myself) that would prevent it from building pressure.

When I did each side, I removed the hose from the caliper and then took the caliper on the bench and pressed teh pistons back in while leaving the hose hanging.

Any insight would be appreciated.

[BoxMN]

When we did a TB, we didn't take the caliper off, just used C clamp to push piston back out. No issues. Silly question, but the cap is back on reservoir? Not sure I am of any help here, sorry.

[MuleShack]

I found a trail blazer forum and one guy had similiar problem. Someone told him to try to bleed the master cyclinder lines...front first then rear.

So I loosed the lines coming from the master cylinder one at a time while giving the brake a pump then redoing each bleeder on the front and it cured the problem...must of had vapor lock.

In my 20 some odd years of doing my own brakes and the wifes, i've never had to mess with the master cylinder before.

I guess I learned something new today.

I also read that they have power bleeders out there. Has anybody tried them? It would make the job easier for a one man operation.

[Macgyver55]

When you removed the calipers did you use line clamps to keep them from draining out?

If not, the master cylinder probably drained down enough to allow air into it and would need to be bled first before you would be able to bleed the the brakes themselves.

[Jeremy airjer W]

In the future you would have been much better off opening the bleeder on the caliper and compressing the piston if you are worried about pushing debris back into the master cylinder.

I have never removed a brake line or a caliper to do a standard brake.

[Scott K]

I know on Windstars, if you compress the caliper without opening the bleeder, there is a good chance you will be putting in an ABS HCU control unit before to long. They just dont like that dirty fluid being pushed backwards into the system.