I am trying to bleed my brakes on my 01. I have been using a Mighty-Vac. And I have been going in the order of RR,LF,LR,RF...I bleed each caliper in this order untill I have no more bubbles coming out. The brake pedal gets very firm. When I turn the ign. on..the pedal stays firm. When I start the car...the pedal has a spongy feel and pedal goes about half way to the floor. Am I doing this in the correct order? Do I still have air in the lines?? I might try going in the order of farthest to closest to see what that does!! Anybody else have any suggestions?? Help Please!!

ZOOMNZ

 

From your description, I do NOT think you have any problems. Make sure you keep the brake fluid resevoir full. The bleeding order should be RR, LR, RF, LF. The brake peddle depresses because the power brake assist is now working, where as before starting the engine it was not working.

Take the car for a test drive, being very cautious with the first couple of stops, to check out the brakes. The brake peddle should depress to about .5 to .8 inch above the gas peddle.

 

Jim, Then I am bleeding in the wrong order!!! You said I should go RR, LR, RF, LF....I was told for year model 2001 I should go RR,LF,LR,RF???? What gives???...I bet if I try in the order RR, LR, RF, LF I will be ok...?? :smash:

ZOOMNZ

 

This implies that you had air in the lines before you started. Why is that so? You definitely must keep the resevoir full to keep from introducing air into the lines. I switched over to the Super Blue fluid from stock which made it really easy to see when the new fluid was flowing through. Also, the Might Vac sometimes causes air bubbles to form, but it is not air from your system, it is from air sneaking in through the valve and plastic hose. Just keep going the way you are and be cautious when you first take it out. I had no problems at all. Good luck! :cheers:

 

Most likely you are OK right now with your order. The LONG line to SHORT line order is basically to minimum contamination of the new fulid with the old fluid. I really don't think you have anything to worry about. :cool:

 

I had air in the system because I am replacing calipers and brake lines!! Do you know the proper "ORDER" for 2001? I dont see any bubbles coming from the fluid with the Mighty Vac. I am using the inserted nipple instead of using the tubing on the outside of valve. May be I am leaving a small amt of air in system with the inserted nipple?? But there has been so much issue over the proper "ORDER" for different yrs!! Just cant get a solid hard break pedal when engine is on...And yes I am using new pads as well!

ZOOMNZ

 

Your original bleed order is correct for your model year. There was a switch in the recommended order, which some people don't know about. That's why you have to be a bit careful about advice you get. As was already said, you can get bubbles from air sneaking in around the lines because of the vaccum created by the pump. This is unfortunate because its hard to tell the source of the bubbles. I have the same pump you do and went back to the old "pump the pedal" method so I absolutely know when there are no bubbles in the lines. I think that you've probably purged any air and the power boost is the reason the pedal moves after starting the car. See how the brakes feel under use. They should feel firm.

I also found out from experience and advice on this forum that you can get a soft pedal from pad tapper due to very hard track braking. If you have had your car recently at a road course, this could also be a source of a soft pedal feel. I recently had my car at BIR and had a soft pedal afterward. Flushing the brake fluid didn't help. I had to replace the pads to get back a good brake pedal feel. I measured the old pads and found that they were in fact tappered. This forum pointed me to the right solution, as is often the case.

- Mark

 

I use a compressed air powered vacuum bleeder and get some air bubbles coming through the line because the seal around the bleeder valve isn't perfect. As long as you keep the reservoir full and bleed long enough you really will get all the air out of the lines no matter which order you bleed in. Once you know you are getting fresh fluid from the reservoir coming through the bleed line you know that brake caliper is bled and all air is out. After you turn on the engine the power brake booster will make the pedal feel soft. When you try the brake make sure the pedal drops to about the height of the gas pedal on the first stroke. This sets you up for heel toe braking since you don't have a large difference in height between the two pedals to bridge with your foot.
Bill

 

I just also bleed my brakes on my 01 with ATE super blue and I also installed speedbleeders http://www.speedbleeder.com . The order for 01s is RR,LF,LR and RF.

I had been at road atlanta a few weeks ago. After the bleed this w/e I still had a soft pedal. I removed my pads and had some taper. I sanded the pads down to get rid of the taper, still have good pad life left. Also I could see that the pads where glazed after I sanded the first pad. I just got done installing them and rebleed the system about 3-4 pumps per caliper. See what happens tomorrow after I give her a test run.

Do NOT attempt to sand your pads down to get rid of taper or glazing UNLESS you have a resperatior/sanding booth.

 

I used the old method, pump the brake pedal and hold. Worked great and took no time at all. It does take two people. We started on the FL,FR, RL, RR.


[Modified by wallstAL, 11:33 PM 6/17/2002]

 

I used the old method, pump the brake pedal and hold. Worked great and took no time at all. It does take two people.

 

zoomnz,

Your bleed sequence is correct for your 2001. When you hold pressure on the pedal and start the engine as you describe, it is normal for the brake pedal to drop because of the vacuum booster.

If your pedal holds solid after dropping initially when starting the engine, I think everything is normal. If it continues to move down slowly, under constant pressure, then you may still have air in the system....or....you could have a master cylinder which is leaking internally.

Good luck.
Mark


[Modified by MDT, 2:04 AM 6/18/2002]

 

I'm doing the same upgrade right now with my 2002 - rotors and ss lines. I also added the SpeedBleeders, a lifesaver when you have to work alone. You are using the right bleed order. We have cross-plumbed brake lines, thus the RR, LF, LR, RF bleed order. I confirmed this in my 2002 Service Manual.

I was using the Motive Power Bleeder pressure tank and there's a warning in the instruction sheet that it doesn't work well in brake systems with lots of air because there's not enough pressure to purge the compressible air. I don't know if this is also true with the vacuum systems. My Power Bleeder didn't get all the air out of my system so I'm having to resort to the pedal pumping method. I tried it some last night and the pedal started feeling better but it's not complete yet.

I'm using the ATE Super Blue fluid and clearly saw the blue fluid replace the stock fluid and there were no bubbles in the line. However, the pedal was still mushy - air was still in the system. I ran out of fluid before I finished so I've ordered more. (My suggestion if someone is going to go this route is to use the cheaper stock fluid to purge the air and then switch to the final fluid for the last fluid repalcement cycle. Oh well, live and learn.)

Here's a very relevant post I found in a search about this:
http://forums.corvetteforum.com/zerothread?id=131882

Here's a revealing final comment by the poster in the thread:

"I finally got the brakes bled completely. It took 5 times , the wife pumping the brakes and a couple 32oz bottles of DOT4, but the pedal is now hard as a rock."

So, you see, it will probably take more bleeding cycles than we thought due to the large amount of air introduced into the system when changing out lines. (I also completely pulled my calipers to paint them on the bench which exacerbated the problem.)

 

You may want to bleed/flush your clutch fluid while you are at it:
https://www.corvetteforum.com/techti...=141&TopicID=1

I would get all of the fluid out of the reservoir with a baster. then you can wipe the inside of the reservoir out. then fill it with brake fluid, I also use ATE super blue.

Here is what the reservoir looks like after 15k miles on a 01 Z06.

 

Well, I have continued to battle this bleeding procedure. I believe I have all the air out...But when car is started...the pedal goes down to about where the gas pedal is and stays there!! IS this what new brake system pedal shoud feel like? Like I said...the pedal is firm at that point...Just thought that with new brake system...(new rotors and pads)..that the pedal would not go down as far.....What do you all think??? Should my pedal stop above the gas pedal with the engine on??? Thanks..!

ZOOMNZ