unbleivable brake problem

[wimpytwins]

this is my second thread i have posted about my brakes. my 93 explorer sport that has a (sas) for the last 2 years had had not one problem with the brakes. about three weeks a go i put new spider gears in the front so i took off the calipers (i didnt take off the lines) did the swap and the used a C clamp to push in the piston in and put them back on. now i have a zero brakes. i stared replacing everything (master cylinder, calipers, new fittings on the lines) i also took out the whole abs system even though i havent had i working for the last two years. i replaced all of the parts one by one and noting worked. now that all of the new parts are in with the car off you can pump the pedle a few times and get it to harden up but as soon as you start the car the pedal goes to the floor. i have bleed the hell out of the system. i think i have put about two 32 oz bottles threw the system. i have never the the master cylinder go dry or even get low. i have no problems with the back brakes infact i pluged off the rear blake line so that i am only dealing with the front. none of the fitting leak i cant see any leaks or wet spots on the lines. what in the hell is wrong with my brakes.
thanks in advance for the help

 

[Doug]

Dumb question but are the calipers put on correctly? are the calipers positioned so the bleeders are on top of the caliper? I know a member on here had a similar problem with his rear brakes and it turned out his rubber hoses where actually expanding when he stepped on the brakes. If you didnt replace the rubber lines (assuming thats what you have) going to the calipers they could be whats causing the problems. when you bleed the brakes are you getting any air out or is it there is just no pressure?

 

[mctoy]

I think DOUG is on to something. Outside of trapped air, or a leak, I cant think of anything else. (You said you have replaced everything w/new parts, and the rears work) Toyotas...at least the newer Camry, Corolla etc, all have 'mushy' brakes. The cure, for them at least...is to replace the rubber 'balloons' with stainless lines. Did it on my 03 Camry and it felt like a different car! Good luck.

 

[CDW6212R]

Check a local fluid line store. I have a Royal Brass and Hose which converted my front lines to stainless steel, for $42 total. Good luck,
DonW

 

[Glacier991]

It might have something to do with the ABS system. Here's the factory manual's portion on this aspect:


Bleed Procedure, ABS System

The anti-lock brake system must be bled in two steps.

1. The master cylinder and Hydraulic Control Unit must be bled using Special Service tool, Anti-lock Brake Adapter T90P-50-ALA and Jumper T93T-50-ALA. If this procedure is not followed, air will be trapped in the HCU which eventually leads to a spongy brake pedal.

To bleed the master cylinder and HCU, disconnect the 40-pin plug from the Electronic Control Unit and install the anti-lock brake adapter to the wire harness 40-pin plug.

a. Place the bleed/harness in bleed position.

b. Turn the ignition switch ON. At this point the red OFF indicator should turn on.

c. Push the motor button on the adapter down. This starts the pump motor. The red OFF indicator turns off and the green ON indicator turn on. The pump motor will run for 60 seconds once the motor button is pushed (you do not need to hold the button down). If the pump motor is to be turned off for any reason before this 60 seconds has elapsed, push the abort button and the pump motor will turn off.

d. After the first 20 seconds have passed, push and hold the valve button for 20 seconds. This bleeds any trapped air from the master cylinder and HCU.

e. The pump continues to run for an additional 20 seconds after the valve button is released.

2. The brake lines can be bled in the conventional manner. Refer to «Section 06-06». Bleed the brake lines in the following order.

l Right rear

l Left front

l Left rear

l Right front

 

[wimpytwins]

everything has been bought at autozone. if there was i leak that made the pedal have no resistance shouldnt a lot of fluid come out of some where? can there be a leak even though everything looks dry? i took out the abs system so i dont need to worry about that. do i need to replace the lines with new metal pipe or can i use rubber tubing. the only reason i would like to use rubber tubing is because it would be easier to rout it form the master cylinder to the caliper.

 

[Doug]

Well, Like i said before when you bleed the brakes are you getting any air out? that'll tell you if there is a leak some where. You can get steel braided brake lines to replace your rubber lines and they're flexible so routing them isnt to much of an issue.

 

[Rhett]

The master cylinder and Hydraulic Control Unit must be bled using Special Service tool, Anti-lock Brake Adapter T90P-50-ALA and Jumper T93T-50-ALA.

Where can one acquire these items?

 

[marragtop]

Before you dump anymore $$ into it, I think you should consider what Galcier posted about the ABS system. In older vehicles, I'd swear it was the poportioning valve, but with the Explorer, I suspect it's ABS related. Seems awful coincidental that you still have problems with all that you've replaced. I'd consider the ABS solution.

Mike

 

[Eneurb]

Where can one acquire these items?

Those are Ford special service tools. They are breakout box adaptors.

 

[Glacier991]

I have them, a couple THEXTON aftermarket ones for sale, and the FORD version I'd be willing to rent.

 

[JimT]

RABS tools

Where did you get the tools a/or is your set complete...how much?

Jim T
Baltimore, MD
443-415-4025
skyepupie@aol.com

 

[410Fortune]

OKay you stated that this is happening both with teh ABS system hooked up and whenyou bypass it correct?

Is there any change with the engine running/not running?

I suspect either you bottomed out your new master cylinder, Autozone sold you a crappy rebuild (Happens alot), or your booster is out.

I do NOT trust Autozone master cylinders. In fact anything rebuilt, electronic or hydraulic skip Autozone and Checker.

Do you still have your old master cylinder?

Also like these guys have mentioned dont start throwing $$$$ at it, it wont solve anything, you need to troubleshoot first.

Did you bench bleed the new master cylinder?
Did the plunger get messed with? the plunger that comes from the pedal, through the booster, into the master is adjustable, and should be re-set to factory position when installing a new master cyl.

The stock master cylinder is built for the correct line pressure for the stock calipers, if you swapped to a solid axle and are running larger/different calipers, this COULD be a problem. There are LOTS of different Ford master cylinder that will bolt up to your booster.

 

[BuffaloXplorer]

Dumb question but are the calipers put on correctly? are the calipers positioned so the bleeders are on top of the caliper?

Verify that this is indeed the case here. I know it should be obvious, but if the bleeders are at the bottom you'll NEVER get any air out and you WILL run through bottles & bottles of brake fluid...

 

[EurekaExplorer]

'93 EB. If my spongy brakes are due to air trapped in the ABS HCU, will disabling the ABS system fix the problem?

Thanks.

 

[DeRocha]

'93 EB. If my spongy brakes are due to air trapped in the ABS HCU, will disabling the ABS system fix the problem?

Thanks.

In short No... If you disable the ABS then the hydraulic control unit won't pulse the brakes during a lock up condition.. Any spongy brake pedal will not be cured.. Did you do something recently to introduce air into the brake system?

 

[EurekaExplorer]

In short No... If you disable the ABS then the hydraulic control unit won't pulse the brakes during a lock up condition.. Any spongy brake pedal will not be cured.. Did you do something recently to introduce air into the brake system?

Thanks. No that I know of, just my ABS has been acting up, activating at low speeds, in conjunction with a sudden increase in brake pedal travel.

Thanks again.

 

[TedJ]

I second the thought about shoddy rebuilds. My dad took his 78 Pontiac Grand Prix to the mechanic to have his brakes done, but shortly after he was driving to work and the brakes stopped working. He made it home and I looked and there was 0 fluid in the master.

The mechanic loosened the seal where the reservoir connects to the cylinder because he had to practically pry the cover off b/c the plastic is so stiff. It was an autozone rebuild with a lifetime warranty, but my dad was so po'd that it broke he went and got a rebuild from a local auto place, Mark Auto. I installed it, bled everything, and went for a drive. Driving really large Pontiac that don't want to stop = . Looked at it and it would not stop leaking from one of the lines. I pulled it out and the SEAT where the line goes had a huge gouge in it. I didn't do it...how it got like that i will never know.

So now I go to AutoZone and get a free replacement for the old one. Not only did it come with a bench bleed kit (nice) but its reservoir felt like it was about to fall off too (sucks) but I went ahead and installed it. It worked but I had to be so careful with the cover.

Mark Auto took the other one back but offered no explination for how or why it was like that..

What ever happened to the real masters with the steel reservoir and that metal band thingie holding the cover on...

Moral: Rebuilds SUCK. You could have fixed one problem and created another and not even know it.

Did you actually totally remove the abs from the system or just unplug it? As long as its there it can trap air, working or not.

IDK how much this helps, but its a good story about rebuilds

-Ted

 

[CDW6212R]

I am not sure yet that the ABS unit air trapped is an issue with pre 95 systems. I never opened my 93 brakes up enough to get air in the ABS. I have the issue in my 95 Crown Vic, because I added the ABS from scratch.

I'd double check everything carefully, then see about any error codes. I saved the ABS unit from my 93, but they shouldn't be too hard to find there. Good luck,