bleeding break lines

[sprayzz]

hey guys i have a 96 vs commodore was just wondering could anyone explain to me how do bleed the breaks as i have never done it before heard its quite easy but am unsure to tackle it...
cheers mark

[INNAWE]

Have you tried to google bleeding brake lines. I have found a few sites that show you and even some that show a clip of it. They may not be your particular car but maybe close.
But if your not confident in playing with your brakes I would steer clear of them. If you dont bleed them properly and trap air in the lines you will put yourself and everyone else at risk.
But in saying that from what I have seen and read they are not all that hard.
From just logic thinking:
Make sure you brake fluid is full and keep an eye on it, crack open the bleeder valve and have someone in the car press down on the pedal, with the pedal down close of the valve and release the brake drawing all the fluid into the lines. Complete these steps until there is no air traped in the lines. You will know this when you open the valve and the brake fluid pours out nice an smooth with out any pops. Just make sure you keep an eye on the Brake Fluid level, you dont want to drain it all and have to start again.

Just so you know I have never done this before so you would probably be better off waiting for someone to deny or confirm this.
Cheers.

[danja]

Bleeding is easy, so long as you're sensible. Basically what you are doing is pumping fluid through the brake lines, and out a hole in the caliper, to blow out any air that is trapped inside.

There is a bleeder nut on the caliper, which you attach a length of hose to (to drain the fluid) and just partially unscrew to let the fluid come out. Then you press down on the brake pedal, which creates pressure in the system forcing the fluid out the bleeder. The problem is that when you release the pedal, you create a vacuum (negative pressure) which then sucks air back in the bleeder (exactly the opposite of what you are trying to do).

There are two options to get around this problem.

1) Get down to Autobarn/Supercheap/Repco etc and get yourself a one-man bleeder kit, it's basically a bit of hose with a one-way valve on the end, so it will let the fluid pump out, but not suck back in again.

2) Get someone to help you. One person sits at the caliper with a ring spanner and loosens the bolt while you press down on the brake pedal, then tightens it while you release it, then loosens again while you press it, etc.

Oh you'll also want a container (empty drink bottle works well) to drain the old fluid into.

Couple of important points:

1) As you bleed, keep an eye on the fluid level in the master cylinder, and keep it topped up as required.

2) Don't re-use the fluid you drain, it'll have absorbed moisture from the air and won't work as well. One 500ml bottle of fresh fluid should be plenty.

[sprayzz]

cheers fellas.... sounds pritty straight forward...might give it a stab.. will see how i go wish me luck!!

[Holdfast]

Mate use the same type of brake fluid that was in it as-well. It's probably never a good idea to mix different brake fluids and always use new stuff; not something that has been partially used and then sat in a cupboard for 10 years.

Be careful too, don't get the brake fluid on your hands, paintwork or if you cleanup with old clothes soak them in water before placing them in the garbige bin as they can self ignite.

[sprayzz]

thanks mate for the extra info... everything helps cheers

[danja]

Yep, the rule of thumb is that an open bottle of fluid is good for up to 12 months, after which it shouldn't be used. For that reason it's a good idea to mark on the bottle when you opened it, so you know if it's still good or not.

[sprayzz]

good idea.. guess it will save alot of time and $$$ that way.

[Andrew426]

2) Get someone to help you. One person sits at the caliper with a ring spanner and loosens the bolt while you press down on the brake pedal, then tightens it while you release it, then loosens again while you press it, etc.

Make sure the bleeder nut is tight BEFORE you release the pedal, rather than while you release it. Otherwise you end up sucking air back into the line.

[Not_An_Abba_Fan]

Do them in the correct order as well. LHR RHR LHF RHF.

[sprayzz]

thanx all...great help!