vt951

I just got done swapping in stainless brake lines, and when I got them all on, I flushed the fluid and bled the system using a Motive Powerbleeder. I just took it out for a drive, and don't get any braking until the pedal is almost to the floor.

While replacing the fluid, I did make a goof. I let the Powerbleeder tank get too low, and I guess it pushed air into the system. I guessed that's what caused the problem. Anybody know how I can fix this?

I did just go around and bled all four corners again, this time with a helper pushing the brake pedal. Didn't help at all.

xsboost90

just rebleed the system. Ive also bled them w/ the motive by filling the resevoir, and just using the motiv to pressurize the system. You have to top it back off before it gets down to the clutch line though. Mine did the same thing a couple weeks ago, had everything apart, bled them and it just wasnt right so rebled them -remember furthest from the mastercylinder first- and it was fine.

billthe3

I think it can take forever for some of the air bubbles to work their way through the lines on these cars. I've rebled my brakes at least three or four times now and it still feels like there is air somewhere in the system.

vt951

Thanks guys. I'll keep trying. Is there a bleeder valve anywhere in the system? (other than at the calipers, of course)

jerome951

Try again w/ a person pumping the pedal. It moves volume much faster than the motive for removing air in the lines.

First, open a bleeder and give the pedal several quick pumps. This helps dislodge any bubbles trapped in the MC.

87944turbo

Your clutch slave of course! I tap on the calipers with a rubber mallet when using the motive and it seems to help get the bubbles moving. If it's mushy more likely than not you've got air somewhere. Be sure to check for leaks at the bleed screws and all your recent line connections as well. Are you bleeding both sides of the calipers?

vt951

Yes, I bled both sides of the calipers.

Clutch slave... thanks, I'll check out Clark's to see how to do that, if a full re-flush and bleed doesn't do the trick.

So, when you say "check for leaks at the bleed screws and all your recent line connections as well", I assume you just mean to look for brake fluid leaking out. Not sure how I would see if air is leaking into the lines.

vt951

I thought you're only supposed to open the bleeder when the pedal is fully pressed in. If you have a bleeder open while you pump the brake pedal, won't that draw air into the system?

jerome951

You can open the bleeder before or while you're pumping down. You get more flow this way since the brake pedal can go lower. Just don't leave it open when you let up on the pedal.

You may have air trapped in the master cylinder that needs to get out to get a firm pedal. It's OK if you pull a little air into the caliper to expel the MC air since you'll bleed the calipers later anyway.

As someone mentioned, tapping the caliper w/ a rubber hammer can help.

Oh, and the clutch slave has no impact on a mushy brake pedal so don't bother bleeding that to solve your brake problem.

When bleeding, make sure you do the outer bleeder before the inner.

87944turbo

Correct, leaking air would be tough to see. I had a leaky bleed screw once and it did exactly what you described where I didn't get any braking until the pedal was almost to the floor.

LUCKY DAVE

Get one of these from Motion Pro. They make well thought out, high quality motorcycle tools for a resonable price.
http://www.motionpro.com/motorcycle/partno/08-0143/
It's just a check valve that goes in your caliper-to-coffee-can bleeder line, but it works like a charm. You simply leave the bleeder open a little and rapidly pump the pedal, the fast fluid movement down the lines quickly drags all the air out with it, and you don't need a helper. The last time I let the resevior go dry while bleeding (and partially filled the system with air....****) I was able to fix my mistake in minutes.
Bitchin.

Bri Bro

Don't worry about it, you will have plenty of time to pump up the brakes on the 25th and it will make you faster in the corners to boot.

On a constructive note, it can take several bleeds to get proper peddle if the system goes dry. It also could have hurt the master cylinder.

vt951

Brian, yes see you on the 25th! I hope the track opens in time. Have you heard anything about it lately?

Did you get your turbo situation fixed yet? I haven't looked at your thread with the mangled vanes in a while.

I think my brakes are good now. I did a full flush and bleed again, and made sure not to let the power bleeder get too low this time, and the pedal is nice and firm now.

I think the air was stuck somewhere near or in the master cylinder. When I flushed the lines, no significant air came out. But when I was done, and I released the pressure on the powerbleeder very slowly, a bunch of air bubbles came up the powerbleeder line. Hope I didn't screw up the master cylinder. I guess if the brakes feel good now then I didn't? Like you said, without brakes I will just have to learn to take corners faster.

Bri Bro

Glad to hear you got the problem fixed. Sounds like you are ready to go and I have to say those control arms are a work of art.

They are working hard to get things in order for the event. Randy sent out a update stating the track was waiting on a permit to complete some repair work and then they can finish the coating of the track which should only take a couple of days. We will be the first group to use the track so it should be interesting. So far, the event is a go but keep your fingers crossed.