Gravity Bleeding

[wildbill]

Has anyone tried gravity bleeding on W's?

I am trying it and I want to make sure I am doing it right.

The MC is full and all four bleeders are open. Its been about 10 minutes and the fluid level in the MC has not gone down. And no fluid is coming out of the bleeders.

 

Any comments? Or pointers?

[Venom]

You sure you have them cracked enough?

[wildbill]

Yeah the bleeders are open enough.

 

I now it takes a while but the entire system is empty. It should go down a little bit right away, right?

[Venom]

It should yes, Ive also heard you need to have the MC cap off and only doing one at a time.

[wildbill]

Yeah the cap is off.

Maybe I need to bench bleed the MC first.

[wildbill]

Ok its working now.

I put the cap back on and closed all off the bleeders. Then pumped the brake pedal a few times.

Opened everything back up and she a drippin'.

 

[Q-Ball]

I think it would of been easier just to get someone to sit inside and do it, but sometimes, when your alone, what can you do. Glad you got it working with a little bit of brake pressure.

[wildbill]

Ya I just got done driving it around. I think I might have to bleed them again.

There is a little bit of sponge in them.

 

I think it would of been easier just to get someone to sit inside and do it, but sometimes, when your alone, what can you do.

 

Amen

[Venom]

There are a few other ways to bleed the brakes yourself. You can buy what are called "speed bleeders" which only let fluid out but no air in, and you could use a one man bleeder kit which is just a vacuum pump with a hose.

[BXX]

The $7 one man bleeder from AutoZone actually works pretty good... I use it all the time..

 

 

Gravity bleeding doesnt work good.. Especially since W-bodies have a split diagonal brake system (not sure but 2nd gens should be the same)

[1990lumina]

Those one man bleeders work fine but make sure the threads around the bleed screw isn't leaking air in.

[rockfangd]

Those one man bleeders work fine but make sure the threads around the bleed screw isn't leaking air in.

you know i was thinking the same thing and that is why i was skeptical and still havent tried them

[AWeb80]

I've been wanting to cylce my 14 yr old fluid out... but haven't.....

 

I just figured if I did one wheel at a time, it would work ok.....and how is air going to get in if the MC is full at all times?

[mra32]

I've been wanting to cylce my 14 yr old fluid out... but haven't.....

 

I just figured if I did one wheel at a time, it would work ok.....and how is air going to get in if the MC is full at all times?

 

you can suck air in from the bleeder screws. Thats why, when bleeding any hydraulic system, you cant let go of the pedal before you close the bleeder screw because its eaisier to suck air in from the bleeder than hydraulic fluid from the resivior.

 

Also, be careful about exposing brake fluid to air. One time I heard that within 8 minutes of being exposed to air, it will soak up enough moisture to make it worthless as brake fluid (fine for a clutch though). When brake fluid sucks up water vapor, it will make the brake fluid boil at lower temperatures. Your brakes do get pretty hot in more extreme braking situations (autocorss, going down a mountain, etc.) and you don't want them to fail when you really need them.

[AWeb80]

I've been wanting to cylce my 14 yr old fluid out... but haven't.....

 

I just figured if I did one wheel at a time, it would work ok.....and how is air going to get in if the MC is full at all times?

 

you can suck air in from the bleeder screws. Thats why, when bleeding any hydraulic system, you cant let go of the pedal before you close the bleeder screw because its eaisier to suck air in from the bleeder than hydraulic fluid from the resivior.

 

Also, be careful about exposing brake fluid to air. One time I heard that within 8 minutes of being exposed to air, it will soak up enough moisture to make it worthless as brake fluid (fine for a clutch though). When brake fluid sucks up water vapor, it will make the brake fluid boil at lower temperatures. Your brakes do get pretty hot in more extreme braking situations (autocorss, going down a mountain, etc.) and you don't want them to fail when you really need them.

 

 

well, what if the MC is full, and I just let the bleeder open....won't gravity drain it out slowly?

[mra32]

It should, but i wouldn't do it. A little hand pump vacuum bleeder is a good investment. So are a couple friends.

[mfewtrail]

Get a bottle/cup/or some other container, fill it halfway with brake fluid. Attach a hose to the bleeder(one that fits very snugly, vacuum line is great for this purpose, just size it up accordingly), and submerge the hose in the brake fluid. Now you can crack open the bleeder screw and pump the pedal without sucking air into the bleeder. Instead, you'll only be sucking fluid back in and any air will rise to the top of the fluid container. Always be sure to keep the master cylinder topped off during bleeding so you do not make more work for yourself. Also, make sure your hose doesn't come out of the submerged fluid while you're pumping the brakes.

[mra32]

Get a bottle/cup/or some other container, fill it halfway with brake fluid. Attach a hose to the bleeder(one that fits very snugly, vacuum line is great for this purpose, just size it up accordingly), and submerge the hose in the brake fluid. Now you can crack open the bleeder screw and pump the pedal without sucking air into the bleeder. Instead, you'll only be sucking fluid back in and any air will rise to the top of the fluid container. Always be sure to keep the master cylinder topped off during bleeding so you do not make more work for yourself. Also, make sure your hose doesn't come out of the submerged fluid while you're pumping the brakes.

 

 

The easiest way is with a couple friends. I like clear tubing for this so i can see what exactly is coming out of the bleeder