Does anyone know how to bleed the hydraulic brake booster---I accidentally let the reservoir run dry will trying to hurry . Lexus manual says the booster must be bled for this problem, but does not tell how.

Have bled them since this, but there is still too much force required to stop the vehicle at times. Thinking of letting Lexus dealership take a shot , but I hate letting anyone work on it (even recently change the timing belt, water pump and pulley without any problems just to avoid any dealer screwup/mishaps), plus when I asked, they said they had never bleed a brake booster before!?!

Any help or info is greatly appreciated.

Thanks,

Jay

 

Hey, does any one know what our brake boosters are filled with....compressed Nitrogen gas, or brake fluid?

ANYONE, please!

thanks,


Jay

 

i have absolutely no idea, but maybe you can go and ask some local mechanic shop?

 

Apparently the accumulator is feeled with compressed gas (probably nitrogen) per the lexus manual (disposal of the accumulator note).

Took it by the Lexus dealership and they bleed the master cylinder/brake booster and said they got NO air, and they don' t know why it is not stopping as well as it should, but at least they did not charge me anything .

Only thing is, when they washed the car, some idiot sprayed SILICONE tire dressing all over the rotors, rims and tires and the damn thing stops worse now than it did before I took it in . Anyway, I'll get it off with some brake cleaner.

Someone posted on the site a while back that fluid does not readily come out of the front brakes during the bleeding process if the car is turned to the ON position (car does not have to be running) because the ABS valving system senses the drop in pressure and closes the valve.....Is this true....do the front brakes have to be bled with the car switched OFF?!

Maybe this is why after bleeding the brakes twice since getting air in the resovoir, I still have BAD brakes?!!!

 

i talked to my old boss about this (he owns his own shop)

and he told me exaclty this

you can bleed the brakes like you would on a nonABS car

but DO NOT turn the key on or ABS goes crazy

i found great info on the Stoptech website

thanks for the info you provided

http://www.stoptech.com/whitepapers/...rakesright.htm

http://www.stoptech.com/technical/

 

I also was forgetful and let the reservoir run dry, and had to live with a spongy brake pedal for a few weeks until I had a chance to bleed again. After running a bottle through the system, the pedal firmed up.

So in my case it was a recoverable error- the air introduced by letting the reservoir run dry eventually worked its way out of the system. Hopefully you'll have the same luck.

 

Thanks guys for the help. I'm planning on bleeding the brakes one last time.....wish me luck.

thanks agian,

jay