Proper bleed on new calipers - Soft brakes on original manual bleed

[dinanm3atl]

Did all new brakes with stainless lines. This includes the calipers. Before had a nice hard pedal. We did a full manual bleed with new ATE fluid. Not the car stops fine and I am not worried but there is still a spongy feel. I searched the forums and I know from previous experience with new calipers you sometimes need to do some extra work. Tapping the caliper with a hammer. Etc.

This week going to manually bleed the whole car again. Have plenty of extra fluid. However reading some thread about ABS pump. Cycling it? Is this required? It hasn't rained in a bit here and the way the brakes are spongy right now getting them to activate(I think ABS works on this car) is going to be difficult.

So full manual bleed again now that I have put some miles in. Tap the calipers with a hammer to move some air through. What else do I need to add to the list to make it 'right'? Track day first weekend of March so want it done and right for that ;)

[jlevie]

If when doing the work the reservoir emptied, there could be air in the brake system that you did not get out with a manual bleed. The first thing to do would be a full flush of the system. That means pushing a measured 250cc through the right rear caliper, 150cc through the left rear, and 150cc through each front caliper. If the pedal is still soft, get the car on a slick or loose surface and engage the ABS. Then re-bleed. An empty, wet, parking lot works well and 20-30mph is plenty.

[dinanm3atl]

If when doing the work the reservoir emptied, there could be air in the brake system that you did not get out with a manual bleed. The first thing to do would be a full flush of the system. That means pushing a measured 250cc through the right rear caliper, 150cc through the left rear, and 150cc through each front caliper. If the pedal is still soft, get the car on a slick or loose surface and engage the ABS. Then re-bleed. An empty, wet, parking lot works well and 20-30mph is plenty.

It did not empty. We had a bottle feeding it 100% of the time. I have done calipers before(not an on E30) and with brand new calipers it took a2nd bleed after some heat cycling to get the extra air out.

So going to do that again with another full bottle around the car. I assume at that point I should be setup really nicely. Any other tips? It sounds like as long as it did not go dry or get air into the ABS pump(which should have been impossible) just bleeding again and getting air out should be good?

[jlevie]

About the only way air can get into the ABS is the reservoir goes dry. Unless you plug the brake lines once they are disconnected from the caliper you will drain the reservoir. Changing calipers & soft lines can be done quickly enough (with a refill of the reservoir during the process) to avoid draining the reservoir. But if you aren't careful and quick that is a possibility. But even then a full flush of the system with a liter for fluid as described above will usually suffice.

[dinanm3atl]

Cool. Thanks. If we put a lot of fluid through the system would it still be required to cycle the ABS? As said we have not had rain on the forecast for a little but but Tuesday and Thursday we will have rain. That will make it nice. Can try to get into the ABS with how the brakes are currently. Hopefully I can make that happen. Then a full bleed again :)

[mlytle64]

age of the MC...original?

when manual bleeding did you push the pedal all the way to the floor?

do you get better pedal pressure on the second pump?

if answer to all is "yes" your MC may be toast.

[dinanm3atl]

age of the MC...original?

when manual bleeding did you push the pedal all the way to the floor?

do you get better pedal pressure on the second pump?

if answer to all is "yes" your MC may be toast.

Yes we did but again it's brand new calipers so have had this issue before where you just don't quite get it bled perfect. And did not have this problem with the previous calipers but they were of unknown age and one was sticking a little. I'll report back.


*edit* Just to confirm went out and pumped the brakes and as I remembered it doesn't get better as you pump. It's the same each pump. It just feels spongy like a little air in there. Sure when I crack open these bleeders gonna get some bubbles.

[dinanm3atl]

Ok I got into the ABS. Full fresh bleed. Got a little air out. Still have it a little spongy. I did not have this issue before the new calipers and brake pads. It feels like the pads just suck. Going to install my track pads to test. Any other ideas to test in the mean time? I had a very hard pedal before. Track in 3 weeks so wanna get it sorted. Old cars are always fun!

[jlevie]

If you got some air out after activating ABS it sounds like air in the ABS system in the problem. There may still be some air in the unit. Repeat the ABS/bleed cycle a time or to more, well until you aren't getting more air out.

[Aahj]

I use this to flush/bleed my brakes. Best tool I've used hands down:

http://www.brakebleeder.com/products/best-sellers/maxpro-professional-brake-bleeder-tool.html

[LJ851]

About the only way air can get into the ABS is the reservoir goes dry. Unless you plug the brake lines once they are disconnected from the caliper you will drain the reservoir. Changing calipers & soft lines can be done quickly enough (with a refill of the reservoir during the process) to avoid draining the reservoir. But if you aren't careful and quick that is a possibility. But even then a full flush of the system with a liter for fluid as described above will usually suffice.

Just a tip when replacing calipers or flexible lines. If you push the brake pedal down about 1/4 of the way and hold it there (a stick or 2 x 4 wedged between the pedal and seat works well) all of your brake fluid will stay in the system. What you are doing is blocking the return port to the reservoir, it works like putting your finger on top of a straw full of liquid.

Save your expensive brake fluid and make less mess!

[dinanm3atl]

If you got some air out after activating ABS it sounds like air in the ABS system in the problem. There may still be some air in the unit. Repeat the ABS/bleed cycle a time or to more, well until you aren't getting more air out.

Some air is used loosely. It was not a lot and could have been from the calipers. It was right at the beginning and then nothing. Anything else to try? You can push the pedal down and it's spongy at first. At some point it does get harder but still feels spongy. Do not get quality braking.

[dinanm3atl]

Another note after a google search. These are Hawk HPS pads and it seems they feel terrible... any other comments on this?

[jlevie]

Some air is used loosely. It was not a lot and could have been from the calipers. It was right at the beginning and then nothing. Anything else to try? You can push the pedal down and it's spongy at first. At some point it does get harder but still feels spongy. Do not get quality braking.

Any air in the system will result in a soft pedal. The fact that you got some out suggests that there still may be air in the system.

I've never had a problem getting the air out of a system, but then I always pressure bleed the system.

[dinanm3atl]

Any air in the system will result in a soft pedal. The fact that you got some out suggests that there still may be air in the system.

I've never had a problem getting the air out of a system, but then I always pressure bleed the system.

Yah the flipside is I have pressure bled plenty of times and don't like the pedal feel. Always done a 2-man manual bleed.

So get into the ABS some more? And repeat? If I have someone pressure bleed the system will that get the air out more easily? I did 20-30 panic stops in the wet and cycled the ABS a lot before the 2nd bleed...