Upgraded brakes - problems bleeding new calipers

[hipsterdufus]

Hey everyone. I worked on upgrading my car's brakes to the 325 brakes over the weekend. All seemed to be going well until I went to try to bleed the brakes. I was doing it the "two-man" way, having my wife pump the pedal to build up pressure, having her hold down the pedal, then I would unscrew the bleeder nipple, let the pressure out, tighten it back down, and have her lift the pedal. Bleeding the brakes went fine on the rears; there was virtually no air in the lines and the pedal had good action. I then moved to the fronts. I used the same method and there was virtually nothing but air shooting out of the lines. After doing this a few times, the pedal goes to the floor all of the time regardless of what caliper I'm working on. Does anyone have any suggestions? I'm pulling my hair out!!!!

[1996 328ti]

Repeat process.
Be sure the reservoir never becomes empty.

[hipsterdufus]

So, since the brake pedal now goes to the floor regardless, should I still have her pump the pedal before cracking open the bleeder nipple? Or is there some other method I should use?

[1996 328ti]

I think you should just repeat the procedure.
I've never used the two person method. I've always used a vacuum.

Did you have a brake problem before bleeding?

[hipsterdufus]

Well, the rotors were warped and I figured it'd be a good time to upgrade to the 6 cylinder braking system. I guess I just should have stayed with the older system; right now, my car has been jacked up in my driveway for 3 days. My neighbors have got to love me...

[mohaughn]

at what point did you remove the old calipers and put on the new ones?

Did you bleed rear brakes,
then remove old calipers
install new calipers
try to bleed front brakes?

When you upgraded the calipers, how much fluid did you lose from the lines?

[hipsterdufus]

I bled all the brakes after replacing the front calipers.

I lost virtually no fluid during the caliper change; I had the new calipers sitting right next to me to go on as soon as I got the old calipers off.

I'm thinking about just breaking down and buying one of these: Motive Products Power Bleeder

It just sucks to spend all of that money on something that should be relatively easy. I should have just had a mechanic do it, for all of the extra cost this is going to run me.

[mohaughn]

First off, when you are bleeding the brakes, don't have the person in the car pump the pedal. That causes the air bubbles to be dispersed through the fluid.

What you want to do is have them push the pedal down to the floor, then crack open the bleed screw, you don't completely remove it. You move the wrench maybe 25% of one complete turn.

You then close the bleed screw, and have them release the pedal.

Repeat until there is no air in the fluid and the pedal is firm.

In some cases, if there is absolutely no fluid in the line, you may have to crack open the bleed screw as the person in the car is pushing down the pedal. That will allow the air to get pushed out as the pedal is going down. Once the pedal is down on the floor, close the bleed screw, and release the pedal. repeat..

[BimmerBum]

Originally Posted by hipsterdufus

Hey everyone. I worked on upgrading my car's brakes to the 325 brakes over the weekend. All seemed to be going well until I went to try to bleed the brakes. I was doing it the "two-man" way, having my wife pump the pedal to build up pressure, having her hold down the pedal, then I would unscrew the bleeder nipple, let the pressure out, tighten it back down, and have her lift the pedal. Bleeding the brakes went fine on the rears; there was virtually no air in the lines and the pedal had good action. I then moved to the fronts. I used the same method and there was virtually nothing but air shooting out of the lines. After doing this a few times, the pedal goes to the floor all of the time regardless of what caliper I'm working on. Does anyone have any suggestions? I'm pulling my hair out!!!!

Start with bleeding the fronts, left front then right. Keep the lid off the reservoir and make sure it stays full. I refill it as I move between wheels.

Silly question... you do have the calipers on right side up?

[hipsterdufus]

Originally Posted by BimmerBum

Start with bleeding the fronts, left front then right. Keep the lid off the reservoir and make sure it stays full. I refill it as I move between wheels.

Silly question... you do have the calipers on right side up?

I'm pretty sure they are on correctly. The bleeder screw is facing up and the springs/clips to hold the calipers face outward.

Just an FYI; I bought the pressure bleeder and will give that a try tonight. If that doesn't work, I'm guessing that one of the calipers that I bought is bad. I hope that's not the case, but I guess I ran that risk when I bought used. I'll let everyone know how things go.

[hipsterdufus]

I just wanted to let everyone know that the pressure bleeder made everything infinitely easier. I was basically done in 30 minutes and the brake pedal is now nice and firm. I can't tell you guys how much easier using this thing was than doing it the "two-man" way. Highly recommended.