Suspect power boster or master cylinder. ???

Bad master cylinder could cause this. Often becomes apparent after a brake bleed. Greg.

Assuming the brakes are properly adjusted, fluid levels aren't low, fluid is properly bled, and the pushrod is not out of adjustment then the master cylinder is suspect. A bad booster will generally give a hard brake pedal.

With the engine off, pump the pedal until it gets hard. Start engine with foot pressed on brake pedal. The pedal will slowly drop. That is normal as long as it doesn't reach the floor. That means the booster is working. If the pedal hits the floor before braking is active I would suggest either master cylinder or air in the system still.

If the brakes work but seem low to floor and improve with a couple of pumps, most likley air. Bleed from furthest away first, working toward the nipple closest to the master cylinder.

steve wrote in news: snipped-for-privacy@4ax.com:

Does the Master Cylinder fluid level stay the same no matter how many times the pedal goes to the floor? If so, then your Master Cylinder seals are bad. You used the "pedal pump" bleeding method, didn't you?

Time for a remanufactured Master cylinder. It's cheap and pretty easy to do yourself.

Here's a Honda page made by me:

won't be 100% applicable to your Toyota, but will give you a general overview on what needs to be done and why.

If you had someone pumping the brake pedal while you were bleeding brakes and the pedal went to the floor, there's a very good probability that the brake master cylinder needs replacement. During normal braking operations, hydraulic pressure prevents the piston in the brake master from traveling too far. Without that resistant pressure, the piston bottoms out and the piston seal travels over uncharted territory, usually resulting in a cut seal because of varnish and crud build-up that the seal passed over.

*Before replacing the master, do as the other posters have suggested and make sure that there isn't any air left in the hydraulic system.

I'd recommend going with a new brake master cylinder instead of a rebuild. I've installed rebuilts before (when working as a brake tech years ago) and in most cases, the rebuilds needed to be replaced within a year. (The shop I worked for had a brake pressure bleeder and it was used extensively to avoid ruining the customers brake master.)

The pedel was going to the floor before I did the rear brakes. It needed the rears done and I thought the problem would go away after bleeding the brakes. I started at the passanger rear and worked my way to the drivers front wheel. That was the only wheel that seemed to have air in the line. I thought that was the answer!!!! Nope, the pedel still seems the same. The car stops but only with the pedel to the floor.

I still have to adjust the rear brakes. spin the adjuster wheel to expand the shoes. could this be the problem?

Should I try bleeding the brakes again? Yes I used the pedel to thhe floor method. wife pushed the pedel down, I opened the bleed valve then closed it and then my wife let her foot up. then repeated. I did pass. rear, driver rear, pass. front, drivers front. Pumped a small container of fluid through total.

Pedel still goes to the floor. Like I said the car stops, I can lock up the brakes but they are not right...

Is there any way to tell if the master cylinder is bad ??

Thanks for any suggestions, I'm getting close to bringing it to a brake place but I cant really afford it??????

Possibly. The easiest way to tell is to addjust the rear shoes.

You can try but it sounds like you did them correctly and in the correct sequence so I doubt if if will make a difference.

Get everything right first, i.e. correct fluid level in the master cylinder, adjust rear brakes, and if the pedal goes to the floor, the master cylinder is what's left.

steve wrote in news: snipped-for-privacy@4ax.com:

Could be, yes. Pull up and down repeatedly on the parking brake lever. This will adjust the rear shoes. Might have to do this for a while...

Even then, it'll take the shoes a while to conform to the shape of the drum before you have 100% optimal braking.

Not yet. Adjust the PB first.

Sounds good.

Read the page I referenced. It tells you how to tell if the MC is bad.

Read the page I referenced. It tells how to replace a MC. They're less than $100, rebuilt.

Great tips and thanks for the time to make the web page. I will try adjusting the rear shoes but everything is pointing to the master cylinder... Your page will come in handy..

Is it safe to use a rebuilt MC???? I haven't seen any rebuild kits? is that an option??? or should I just pay the $200 for a new MC..

Thanks again..

Steve

"Steve" wrote in news: snipped-for-privacy@giganews.com:

You don't need new. You can buy rebuild kits, but you're better off to replace.

Many places have remanufactured MCs. Call around. AutoZone Kragen Pep Boys UAP/NAPA the dealer etc.

The Master Cylinder is the more likely of the two choices you asked about.