Another rear brakes thread

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I just did the same thing... Last weekend. Wife got cranky 'cuz she had to sit in the car so long pumping.

You've still got air in the system. Use the order Dynosoar stated and gently tap each backing plate where the cylinder is and caliper with a plastic or rubber mallet before each bleed to release any trapped air. It may take a couple of go - arounds.

Did you use the stock MC or a 1" ?
 
I used the stock MC. I will try bleeding it all again.

What about this... Is it possible that flushing all the new fluid through the system fouled up the seals in the master cylinder? I'm just assuming that it's the stock MC, but can't be sure. While the vehicle is on, I can't build up pressure in the pedal but when it's off it does build up pressure.
 
That's 'cuz the booster is adding leverage.

You have air in the system. Unlikely flushing would mess up the MC but anything is possible. Are you loosing fluid, anywhere? If seals on the MC go bad, could leak into the booster, and you might not see it, but you'd still be losing fluid.

More than likely you've got air in the system that I found to be very difficult to get out with the stock MC and 4runner calipers. I dunno if it wouldn't move enough fluid or what, but that's why I eventually went with the T100 version and that solved it. Though others have stuck with the stock MC and lived with a spongy peddle.

I didn't have access to a pressure bleeder, and that might do it. You might be able to rent borrow one from Vatozone, etc...
 
In good news the e-brake is working great! Just gotta figure out the REAL brakes! :mad:

how far do you have to pull up on the parking brake lever to get the rear brakes to work? 1/2~3/4 or 3/4~full? Reason I ask is because I just got finished installing a new MC and rear brake adjustment. Before i adjusted the rear brakes, my lever pulled all the way up. After properly adjusting them, it only pulls 1/2~3/4 of the way, much shorter than it used to.
 
I agree with the guys who are saying you still have air in the system.
It often helps to start the bleeding at the MC then bleed at the wheels in the correct order.

To help identify where some/most or all the air is, you can try clamping off the flexible brake hoses.
Really you should use a proper tool (line clamp) for this but if you are very carefull it is possible to use multigrips or vicegrips.
Be VERY carefull not to clamp so hard that it does damage to the flexi line!
You need just enough pressure to stop the fluid flowing in the line, no more.

Try clamping the rear brakes flexible hose first, and see if it improves the pedal travel and hardness.
If so the air is (mainly or totally) in the rear lines and wheel cyls.

If clamping the rear flex hose doesn't make any difference, try the flex lines at one or the other caliper, or even clamp both off and try the pedal.

What you are trying to achieve is to isolate exactly where any air is trapped, and then bleed the **** out of that part of the system.

Hope this helps and keep us informed.
 
Wow, GM60 you really know your stuff. I'll give that a try before I drop the $$$ on a new master cylinder. I just got some new snowboarding gear so money is getting tight. Thanks!
 
Here's another tip regarding bleeding your brakes.

The only time you should ever push the pedal to the floor during bleeding is if the master cylinder is brand new or has just been fully rebuilt.

Never push the pedal to the floor on an old MC!
The reason is that the last part of the bore inside the MC is not usually ever in contact with the pistons and seals. Because of that, an old MC can be rusty, pitted and full of gunge it the last part of it's bore. If you push the pedal to the floor, you are pushing the old soft seals in your old MC down into that rusty pitted gunge, and sometimes this can end up destroying those seals, and the MC that used to work ok, is now stuffed.

Only push the pedal about half way down, no further during bleeding with and old MC.
 
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