My First Time Bleeding the Brakes (I'll need guidance!)

Ok, so my brakes haven't been performing at optimal level lately and I'm thinking it's time to bleed them. I'll try to be descriptive as possible so it will be easy for you guys. Oh and they are power, disks in the front and drums in the back.

Symptoms:
1. I have to depress the pedal almost all the way to the floor before the brakes fully engage. 2. When the brakes are completely depressed I usually hear an air-type sound, like air is being sucked or something? 3. I have had the car for almost a year now (it's my almost daily driver) and I have never done any maintenance on the brakes system so I figured I better give it a check up.

General Questions:
1. How long should this take? I plan to do it old fashioned with out any of the new tools (someone sitting in the car pumping the brakes and the other at the end of the line). 2. I have heard both directions to start at farthest and closest brake line from the master cylinder, so which is it really? 3. I've read about people completely replacing the lines and master cylinder, and I hope to the Lord I will not have to do this, but how difficult would that job be? 4. What are your personal tips and techniques that could most likely make it easier for the new guy, because I am willing to take just about any advice.

All responses will be greatly appreciated! :TU:

 

As for bleeding, start at the shortest line and work your way out.
In general, since it's not that much work to do you might want to pull the wheels and look to see if the brake liners look like they still have material left on them.
I noticed that you didn't say anything about pulling the master cylinder lid and seeing what the level of fluid is, so start there. If it's low you have probably sucked air. Look at the wheel cylinders on each wheel closely and see if you can see any fluid that has been leaking. When you look at the brakes you want to look for any fluid in there also. If you have any leaks, you want to know it and take care of it right away. Brake fluid inside the brake drums will cause them to fail because they are essentially lubricated which reduces the friction that they use to stop you.
Probably bleeding them is all you need, but you want to check everything.
When you bleed them, you don't want to quit when you stop seeing air, you want to go till you see good clear fluid coming out.

 

I'm sorry I forgot to say that I have checked the level periodically and it is full, I have not been losing fluid. And also what fluid should I use while replacing the old stuff?

 

Could a bad booster also be the cause of higher rpm's at idle? I remember hearing that something with the brakes could effect the rpm's at idle...

 

Alright thanks, Adam. :TU:

 

Oh and by the way, is replacing the booster difficult for a novice like myself? And where would I find one that is correct for the lark- A place like Summit, Jegs, or even the local O'reilly's?

 

Alright, thanks for all the help. And seeing how I am more of a budget guy right now than a purist I'm probably going to have to go with the lesser expensive of the choices, but someday when I have the money I'll be sure to try my best to keep all our Buick pals in business! :beers2:

 

I used one way bleeders. I really liked them. They are bleeders that have a check ball in them and you can bleed the brakes by yourself. You just take out the old ones, put in the new ones and start from back to front.

It only lets air and fluid out and none can get back in. Its sweet. Go get four. Its nice. Cheers.

Gary

 

Hi Matt, this is the procedure I use when bleeding my brakes:

Top off brake fluid, have a buddy or your wife/girlfriend press the brake pedal five times in sequence then keep the pedal firmly pressed while you open the first airbleeder.
The brake pedal will move to the floor when you open the bleeder, close the bleeder when no more air/fluid comes out, then release pressure on the pedal.
Do it again in the same way, keep on flushing until fluid is transparent w/o airbubbles.
Move to next wheel and do it again.
Make sure that to top off the fluid during bleeding. I use DOT4 fluid.
I think DOT5 is silicone based and Im not sure if it works well in old cars.

I use a transparent hose attached to the bleeder, that make less mess and makes airbubbles and dirt in fluid visible, use a lamp if its dark behind the wheel.

Problem with "long" travel of the brake pedal can be caused by stuck rear adjusters, = too long distance before the pads have contact with the drum.
When you remove the drums to check the rear linings remember to clean and grease the adjustment screws.

 

Matt
Based on your description, I think Adam is giving you the right advice. You are not adding fluid to the system. The system is not down on fluid and you are hearing the air gush when stepping on the pedal. Sounds like the brake booster is leaking vacum internally when depressed. The only part I might add to his recomended procedure is you do not need to disconnect the brake lines from the master cylinder to unbolt the master cylinder from the booster. Just pull the cylinder away from the booster when you unbolt it, but don't kink the lines. That will eliminate the need to bleed the brakes after you replace the booster. Good luck.:beers2:
Scott

 

I agree 100 percent. If you are not down on fluid, you are probably looking at the booster.

 

I only have one concern with a defective booster. Even if the booster is bad you should still be able to maintain good brake pedal travel. At least that has been my experience. The effort required to push the pedal is of course increased if the booster is no longer providing vacuum assist but you can still stop the car with the same pedal travel.

I always thought there is enough of a mechanical link inside the booster between the brake pedal push rod and and the master cylinder so brake line pressure should still build at a normal rate of pedal travel without vacuum assist. The pedal should not go almost to the floor unless the master cylinder is bad, lots of air in the system or there is a leak somewhere.

 

Thanks guys... Do you think I should replace the booster and the master cylinder just to prevent future problems, or should I just do the booster for now? And is there a specific brand or model I should look for for my daily driver?

 

From what I know everything is original.