Bleeding Brakes from Scratch? new lines and everything

[RizzoRat]

Well we finally replaced all the brake lines with new stainless steel ones, redid the calipars, new bleeders, new resevoir. So now were trying to bleed the brakes, and something just does not seem right. Im pumping...and pumping....and pumping, and theres no fluid coming out of the bleeders, and it seems that little or no bubbles are popping out of the master cylinder. So the level is going down EVER so slowly. Is something wrong? or does it just take like a days worth of pumping to get fluid in the whole system. Any responces would be greatly appreciated.

 

[Mike McKown]

Brake Bleeding

I would do one of two things:

Some will disagree but go buy a mity-vac pump from your local auto store and follow directions (about $30-$60 depending on model).

Open your bleeder screws and let them gravity drip. When you get a drip, close that screw. Keep an eye on your resevoir level and don't let it go dry. After all valves(screws) have dripped and been closed, put somebody inside and resume your pumping method to get all the air out.

With either method, if you can't get a particular caliper to bleed, your flex hoses would be suspect to collapse on the inside, especially if they have any age on them.


If it makes you feel better, everyone that bleeds Corvette brakes complains about it, including me!

Hope this helps. It works for me.

Mike

 

[Eric]

Having just gone through the same experience, I know it's frustrating. The problem you are encountering is that when you replace darn near everything you end up with an unbelievable amount of air in the system. I used a combination of vac and manual pumping but, in hindsight, I wish I had started with gravity.

One piece of bad news. Air bubbles are bound to be in your system even after you've bled it and are getting clear fluid. This is to be expected as it can be tough getting it out of all of the nooks and crannies. In my case, I bled the system once and drove it with a few good firm stops. The pedal softened up a bit and I bled it once more until the pedal was firm.

One suggestion, click on the "search" link at the top right and look for brake bleeding related posts in the 68-82 forums. We've all been through this and there is a wealth of info here on this topic. It also may help just to read what others have gone through.

Best of luck!

 

[pizza3260]

bleeding brakes

rizzo,

gravity is the only way, open bleaders pump 25/50 times and let it sit for 24 hrs, pump again till you see some fluid, close bleaders and start letting the air out.

good luck & have patience

 

[vigman]

Ok... what I did Brake power bleeding

K&D makes a tool that clamps to the top of your master cylinder and allows you to PRESSURE POWER BLEED $40.00 or so bucks

( via some plumbing that you must provide another $35.00 bucks)

You will need access to an AIR compressor with a moisture trap that WORKS!



I have my regulator set for 12 psi.......


IF YOU HAVE A NEW MASTER YOU HAVE TO BENCH BLEED IT !!!! IF YOU DONT

Rut Roo Shaggy

If you need these directions ask me.

Assuming you have a bled master......

Brake lines & caliper empty

Get some tubes (1/4 aquarium air line) and 4 mason jars

Put a nut on the bottom of each hose
( thread the nut over the hose ) to keep it the bottom of the mason jar.


Open all the bleed screws up.
Hook up tubing while filling the rez.
Make SLOW STEADY pumps till the fluid starts filling the mason jars... Keep bottom of hose in the brake fluid!!! so no air gets sucked back in!

( Note here the rear calipers have an inner & outer Bleed screw use the outer one first... then repeat for inner)

Ok got fluid in all 4 mason jars..... good stream?

Close bleeders!

Now TOP the master off.....

Attach K&D tool

( Cutting to the science lab interior )

So here's the deal.....

You have 4 pistons per caliper right
X4 wheels...right?!

( as far as I'm concerned )

The pressure system is the ONLY to bleed the system correctly.... here's why.

When you press on the pedal you are taking that 4 or so inches of stroke on the master and splitting it 16 ways ( 4X4 )

But you only have to move a TINNY bit to get the pads in contact with the rotors.


When you pressurize the system not only do you FORCE fluid down the lines you also are pushing OUT on the caliper pistons..removing that slop as well.

You cannot VAC bleed Vette brakes for 2 reasons

1) The VAC will pull back on the pistons so the calipers are not PROPERLY filled.

2) The bleeder screws are not precision threads.. as there backed out a bit... wiggle it... feel the slop... air can leak around those as well.

SO DON'T WASTE YOUR TIME!

( Cut back to garage...with you working)

So starting from the furthest tire back Right rear........bleed away.

It will take some time getting used to working this way, but it is FAR superior & faster.

Now the bad news

a)Your working with brake fluid under pressure... so when you disconnect the bleeder adaptor... your gonna get a PSSSST of fluid everywhere... make sure ALL your painted surfaces are covered.

b) You will have to top off the master more often than your used to...because your forcing fluid down the lines


Adaptor plumbing

2 ) Male quick disconnect air line fittings

1) Female quick disconnect air line fitting

1) Inline air shut off valve

1) Mini regulator 0-20 psi with gauge on out line
Misc rigid pipe fittings

So from your air hose in the shop
( assuming female here)


Male quick disconnect
Female / Female pipe adaptor
Regulator assembly
Female/Female 90 elbow
Small extension m/m
Air shut off valve
Small extension m/m
female quick disconnect


Male Quick disconnect for top of K&D tool

Your done!

Are you scared?



Vig!