RainJ

It was suggested to me that I post in this forum as you change fluid and brake systems often.
Thanks in advance
Rain


Installed new eradispeed calipers and powder coated rotors.
Drained brake system completely over the course of about 3 or 4 days I guess. Pulled res. and cleaned gunk out of it.

Front calipers are on correctly - rear bleeders are closer to the top than the bottom.. so feel everything is on ok.

Refilled with synthetic fluid.
left all 4 bleeders open.
2 days later two of them were showing fluid. Closed them off. another day later still nothing thru the other two bleeders.

I pumped brakes while my mechanic opened the bleeders. Did that 2 times around. Put wheels back on and started test drive.
No brake response until buried on the floor.

Manually bled them again 2 more times.. still no strong brakes.

Bled the master cylinder.
2 times

bled brakes again - with wheels on this time.
still not any better.

Bought a pressurized bleeder at the parts store. 80-120 lbs of pressre from the compressor.
Pas. Rear brake gave me air bubbles for a minute and then steady fluid.
The 3 other calipers had tons of air in them and seemed to keep pulling in air..
strangest thing!

Any chance the bleeder screws have gone bad and are causing the insertion of air, not letting me power bleed the system?

Armycop

Rain,

From what you describe, it sounds like you're pulling in air. It's possible that the bleed screws aren't tight, although I'd double check the lines. Have you tried a "leak down" test with the power bleeder?

Pressure the brake system with your power bleeder, and then check for fluid leaks around the lines, esp. your master cylinder. What year 'vette do you have?

EDIT: from your sig I see you have two; which one we talkin' bout here?

sothpaw2

What happened to your Avatar? You've had since the corvette action center days and I under stand the need to change things up, but? She was a nice looking blond, put a hat on her if you must.

As for the bleeding--the pressure bleeder is a good idea but I only use 15-20 psi in mine I would not suggest going higher. I'm not sure what you meant by "bled the master" but you must never let the fluid level go down to the hose that feeds the reservoir.

I think you have alot of air and need to keep bleeding, unless you broke something by overpressurizing or something really isn't installed right.

RainJ

The bleeder I used - this one has a feeder bottle - like theone in a hamster cage - full of fresh fluid and resting connected to the res above master cyl.

run air line from compressor to another canister that uses the vac. created by the 80-120 lbs of air to pull air and fluid thru the lines.. that canister has a tube connected over the bleeder screw.

c4cruiser

I would not have let the fluid bleed out like that. Even with replacing calipers, the amout of fluid lost and the small amount of air in the flex lines and new calipers would made flushing and bleeding an easy step.

The two bleeders that did not show any fluid probably meant that air had entered that line had hit a high spot in the line (above the caliper) and there was insufficient fluid behind it to allow the air to move on to the caliper.

Did the new calipers already have bleeders installed? Did you replace the bleeders with something like Speed Bleeders or re-use the bleeders from the old calipers? There is always a possibility that replacement bleed screws were not the correct type for the calipers or that the stock bleeders don't have the same profile that the Baer calipers need. Carefully remove the bleed screws and check for cross-threading. Cross-threading will allow air to be sucked back into the line.

From your original description, you did do a bench bleed of the master cylinder, right?

There is also a possibility that the gravity draining you did caused air to get into the ABS system. That should be bled also but you may need a scan tool to bleed the ABS pump and its lines properly.

RainJ

Yes, we didnt bleed the master cylinder until after we had bled the calipers a couple times..
Someone else suggested raising and lowering each end of the car to work the air thru the lines, but I think thats further down the line with this Corvette. (btw, its the 2000) Sorry for the confusion.
The calipers were powdercoated by a forum member and sent to me without bleeders. I took the bleeders out of my stock calipers.
These are C5 calipers, just powdercoated. The rotors are Eradispeed 2 piece, fwiw.

The bleeders screw in and out easily so I don't suspect cross threading, but I guess it only takes one to mess it up.

So from what I have posted, do you all think its just air in the lines?
(or have I killed my master cylinder by letting it sit empty a few days?)
I am getting ABS warnings in my DIC -

Would a costly trip to the dealership remedy this? (as I don't have the scan tool)

ErnieN85

This bleeder your using, does it pull the fluid out the bleeder screws like a mity vac?
if so then yes you can have air leak at the bleeders and it's really hard to get it right.
The power bleeder to use puts a pressure on the maste cylinder cap and you just open the bleeder screws one at a time, making sure to keep the master full. Since you let the system open and so much air into the abs controller a TechII bleed might be the only way but I'd try a couple of bottles (quarts first)
Also the synthetic fluid.........make sure it's not silicone DOT 5. that stuff will not work right in an ABS system. Dot 3,4 and 5.1 is the right stuff

AU N EGL

I think you are using too much air pressure.

The Motive power bleeder with 15-20 psi is all that you need. Put fresh DOT 4 or DOT5.1 brake fluid in the MC. Put on the Power bleeder cap and pump up to 15-20 psi. Then go to each of the bleed screws and open with a 10 mm.

Let it drain into the bottle. Close the valve WHILE there is fluid flowing or you will get air into the calipers.

and get rid of those speed bleeders. Just use the normal bleed screw and a 10 mm

Dont use a vacuum to pull the fluid out, just let it drain into an empty plastic bottle with a tygon tubbing attach over the bleed screw end and into the soda bottle

RainJ

THe bleeder im using is like a yard insecticide sprayer.
The stream of water rushing thru the handle of the yard sprayer pulls chemical up and into the water stream.

The Bleeder does it with air. As air passes thru the handle of the unit on the right, it creates vac. pressure and draws the air and fluid from the res. to the calipers/bleeder screws. (I dont have speed bleeders in, just the old bleeder screws I removed from the original calipers)


The tube from the bottle on the right connects to the bleeder screw and the fluid ends up in that container.

The bottle on the left is inverted and sitting in the master cylinder res. to replentish the fluid as you pull it out at each caliper.

RainJ

Fluid I put in is Valvoline SynPower Full Synthetic.
Exceeds DOT 3 & DOT 4

AU N EGL

The fluid is fine, But something is not working with that system to get air in your lines.

Time to go to the old two person bleed system. New fluid in the MC, one person pumps the brake peddle three times and on the forth pump, the second person opens the bleed screw and allows the old brake fluid out of the caliper.

Remember to close the bleed screw before the fluid flow stops

do this with each caliper 5 - 6 times

RainJ

Thanks - Thats what we did prior to gettin the power bleeder.
But don't want to replace the master cylinder if its just air in the lines.
We were pumping three times and opening bleeder on third time.

But like you say, gotta do it 5 or 6 times.

Scooter70

Take a rubber mallet and bang the calipers around a bit. Air can tend to find pockets inside the caliper where they won't be pushed out but just bleeding. You need to knock them around and shake things up.

Falcon

Before replacing any parts, I'd take the car to the Chevy dealer and have them do a Tech 2 bleed.

From the sound of what you did in draining the system dry is that you got air into the ABS module. They can cycle it with their scan tool at the dealership. You'll have a hard time doing that at home.

RainJ

Will do both of those
Thanks guys!
(now please send me some spare time to do this)
HAHA!

NavyVet

Absolutely right! Great clear explanation of an often error-prone procedure. For sure, do not exceed 20psi max on the bleeder. It sure sounds like you have an air leak somewhere. But, your symptom of nothing through 3 bleeders would indiate a large one with noticeable leakage.

Therefore, I would look for blockage that is preventing fluid from going through. Without obvious issues, it may well be in the ABS - you will need a Tech-II to properly bleed it.

One more suggestion - it's a 10mm for the bleeders, but using a 10mm "flare nut" wrench helps protect the fittings from rounding off.

RainJ

Its a totally diff. type of power bleeder Im using -
(see pic from my post)
I dont pressurize the resivoir - the air pressure pulls the fluid at the bleeder.

trackboss

It is VERY common to be fooled by get air from the actual bleeder itself. It either comes in from the seal where the tube meets the bleeder or the bleeder screw itself. Just something to keep in mind. Good luck!

-V

SouthernSon

The very first step is often overlooked by some but really makes a difference for rock hard brake pedal feel: PUMP the pedal several times, slowly, to the floor with key OFF. This relieves residual vacuum pressure from the power assist. VERY important. Then proceed with the procedure.

Also, as stated above, the air bubbles are probably being syphoned around the threads of the bleed nipple. No problem if this is the case.

Oh yeah, I have the Phoenix $300 vacuum pull system in the garage. Ain't wuff a dang! I bought the power motive pressure system for $50 and it works like a charm!

RainJ

THANKS again gang -
A suggested vendor for the Motive unit?

http://www.eurosportacc.com/brakebleeder.htm