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nitrouspaul
09-20-2003, 11:47 PM
When I hit the pedal hard the pedal is stiff and the car pulls to the right as well the braking is very poor and the front right locks up and the abs kicks in.

When you push the pedal slow the hardness goes away after about 2 seconds and the pedal goes down and the brakes work as they should. I have a new accumulator, the abs pump is working ,at least I can hear it I never checked the relay for intermittant operation, changed both front calipers thinking the left was binding part time. Also put on new hose on the left.There is fluid in the reservoir and the brake lites and abs light s do not come on in the dash. The system has been gravity bled and then pedal bled with some air found in the front left. This problem still persists but to a slightly milder degree. Anyone with some ideas here....

MercsSC
09-21-2003, 05:26 AM
in the system ....when I did my accumulator ..I had to bleed the master....3 brake lines ...are connected to the master /pump assembly ...top left is the rear curcuit....top right is the is left front..and bottom one is right front ..this is looking at it from the front under the hood ....wrap a rag around the lines .. turn the ignition on to prime system ..have someone step on the pedal.and hold..and slowley crack those lines open ..to bleed out the master ..there should be lot's of pressure..
may have to prime the system a few times ..to get all 3 lines bleed ...then move on to the calipers ..if you need to after that ...I didn't have to ...after bleeding the master ...there is only one ABS failure that matches ...what you are saying ...with the ABS lites off...and that comes down to replacing the... solenoid valve block ....
but test says...bleed brake system ...to confirm condition exsist..and I think it is just air in the system......dave

nitrouspaul
09-21-2003, 06:28 PM
problem only happens when it gets hot. when it is cold or for the first hour of driving everything is ok. cant be air , any other ideas. besides how will air get into the sytem and if it it did I changed the asccumulator in may of last year and the problem started about 2 months ago.

MIKE 38sc
09-21-2003, 07:25 PM
Sounds like something in the solenoid block then.
I hate this crappy brake system!:mad:

nitrouspaul
09-22-2003, 05:41 PM
solenoid block ??
where is that???

rlong
09-22-2003, 07:34 PM
i would check the brake hoses at the front wheels sometimes when they get hot they swell closed inside and make the brake drag in that wheel i have more trouble with hoses than calipers

turbospeed
09-23-2003, 12:42 AM
a little off topic but,


i have a 1990SC that had the ABS removed , still has the computer in the back i want to reinstall the abs system , should i install a 92+system or just install whats missing of the original system

nitrouspaul
09-25-2003, 05:54 AM
I shall check the hoses

nitrouspaul
04-20-2004, 11:15 PM
So in trying to fix this problem I have now replaced both front calipers,the brake hose on the left and bled the entire system.

The problem still persists with the front left not working very hard when you hit the brake pedal suddenly and the car pulls to the right.

When you depress the brake pedal slowly everything is ok. It feels like the hydraulic fluid is going into the lines and down to the calipers ok except when you give it a fast hard apply. Then it feels like a blockage and the pedal wants to fight with you until a few seconds and then the pedal goes down.


Any ideas here again. Sorry to resurrect this idea after 5 months again but I still have the problem.

TbirdSCFan
04-21-2004, 10:21 AM
To me, it sound like the main valve (aka master cylinder) is hosed. Doesn't sound like any of the electrical parts. One of the interior seals may be torn. I'd search around here or on eBay for a replacement, or send it off for rebuild.. or if you're gifted, patient, and resourceful, tear it down and fix it yourself. :o

xizor
04-21-2004, 12:38 PM
When you depress the brake pedal slowly everything is ok. It feels like the hydraulic fluid is going into the lines and down to the calipers ok except when you give it a fast hard apply. Then it feels like a blockage and the pedal wants to fight with you until a few seconds and then the pedal goes down.
I once had a sidekick that id the same thing hought I didnt had the time to fix it since the tranny blew up ... I can tell you that I did check every hose and had bled the entire system too (had no abs thought) and I still had the problem ... mostly the first time of the day I hit the brake ... so since sidekick are pretty simple mechanics I'd say that its the master cylinder ...

tcshum
04-21-2004, 04:12 PM
Nitrouspaul ... did you ever change the solenoid valve block? I ask because I have the same problem on my 89 and wondering if this really fixes it.

MercsSC ... have you done this fix before? If so, was it successful for you?

Everything I have read says the SVB is the culprit, but I don't know if anyone has actually done it.

Thanks

nitrouspaul
04-22-2004, 08:52 AM
Thanks for the reply. No I have not changed the SVB but it might be something to consider. I also suspect it could be the piston in the master as ther are seals and lands there but if it is a 3 way system and the fronts are split how can this symtom occur.

I am still looking for a reasonable answer here or someone with the same experience as I have thrown 600 dollars at this now and still no joy........

When you hit the pedal suddenly the sterring wheel jerks to the right for a second until the fluid pressure "catches up" on the left caliper. Annoys the hell out of me and I feel is unsafe too. I am going to tryerc sc suggestion and bleed from the master if that fails then the master will have to come out. Is this going to be easy or hard.... :confused: .

Mike8675309
04-22-2004, 09:59 AM
Make sure you're thinking about this system logically. #1 - this is a hydraulic system. Thus if you are applying pressure at one end of a hydraulic line, the pressure will appear at the other end.

Have you checked the rear brakes on this thing at all?

If you've removed the posibility of the calipers. Removed the posiblity of the ABS Accumulator. Removed the posibility of the hydraulic pump. What's left?

I can only come up with: Rebuild the ABS master cylinder.

Make sure if you get it rebuilt that you tell the people doing the work why you are having it done. That way the are looking to make sure that issue is resolved when they rebuild.

tcshum
04-22-2004, 03:22 PM
Here'e my story ...

My 89 occasionally pulls to the left when I jab on the brake. It doesn't happen that often, but when it does, it's always a heart stopping adventure.

I've had a NEW ABS actuator intalled (this was way before Prior did them) by Ford outside of my warranty period. I thought it worked, but the problem reappeared. I changed both front rotors, calipers, pads, and caliper pins. I also verified that my front suspension is tight as well.

The only thing I can think of is when Ford changed the unit out, they did not do the solenoid valve block. Does it normally come with a new ABS actuator?

Nitrouspaul ... don't fell bad ... I sunk way more into this brake pull than you! :)

What i'd really like to know is if anyone had the same brake pull fixed by a solenoid valve block replacement. In theory, I think it would, but I want to know that it worked for someone before I sink more $$ into the problem.

Any suggestions welcome!

nitrouspaul
04-22-2004, 09:34 PM
I went to my mechanic this morning to further discuss this problem and I told him that I noticed that the new rotors in the back are showing signs of uneven wear. I mean the right rear looks like it is hardly working cause the cross hatch from the factory is still there. So we determined that the sytem is a criss cross. Means that the right front and left rear work together.
This means that my front left and right rear are slow to work or have a restriction somewhere. This makes sense cause when the car pulls to the right it also feels like the back end is pushing and the car feels like it is trying to twist a little.

We are going to pull the lines off a dist block somewhere. I think there is another one after the svb that splits the two sides. Corect me if I am wrong her anyone, now what should really be my next move....

Mike8675309
04-22-2004, 10:45 PM
I'm not sure that's how the brakes are setup.

The front are hooked into the ABS system and can also be operated if there is no hydraulic assist. The rear brakes are non-functional if there is no hydraulic assist. So I'm not sure how they could be plumbed to be criss-crossed.

tcshum
10-12-2004, 03:45 PM
Ever get this problem resolved? I haven't driven mine until I can get it fixed.



I went to my mechanic this morning to further discuss this problem and I told him that I noticed that the new rotors in the back are showing signs of uneven wear. I mean the right rear looks like it is hardly working cause the cross hatch from the factory is still there. So we determined that the sytem is a criss cross. Means that the right front and left rear work together.
This means that my front left and right rear are slow to work or have a restriction somewhere. This makes sense cause when the car pulls to the right it also feels like the back end is pushing and the car feels like it is trying to twist a little.

We are going to pull the lines off a dist block somewhere. I think there is another one after the svb that splits the two sides. Corect me if I am wrong her anyone, now what should really be my next move....

nitrouspaul
10-12-2004, 07:51 PM
nope still drivin it like that. Nonbody seems to know anything.. can be dangerous at times.
this car sucks ****.....

Ever get this problem resolved? I haven't driven mine until I can get it fixed.

tcshum
10-12-2004, 08:00 PM
Does that mean you tried replacing the solenoid block and it did not work?


nope still drivin it like that. Nonbody seems to know anything.. can be dangerous at times.
this car sucks ****.....

nitrouspaul
10-12-2004, 08:20 PM
nope nothing done except bleeding and new calipers up front. brake hoses too. still same problem.
Does that mean you tried replacing the solenoid block and it did not work?

JMVaught
08-13-2005, 08:58 PM
I know this is one hell of a thread resurection, but I've been having the same problem and I'm aiming at the SVB to replace. Anyone know where to find one w/o the entire ABS Assy?

tcshum
08-13-2005, 09:46 PM
You can try Prior Remanufacturing for a rebuilt one, but they're probably going to want to sell the whole assy.

If you go used, you can find the whole assy for $100-$200 on ebay or in the parts for sale section.

Follow up and let us know if it works.



I know this is one hell of a thread resurection, but I've been having the same problem and I'm aiming at the SVB to replace. Anyone know where to find one w/o the entire ABS Assy?

JMVaught
08-15-2005, 01:48 PM
Found a good used Absent Braking System and it's on it's way and another one coming for parts (VERY CHEAP). If you guys want to check the SVB, you can DIY by following Duffy Floyd's article (http://www.35ththunderbirdregistry.org/Tips/ABS.htm). Basically you d/c the SVB service harness and measure resistance. If you're out of the given range of 5-8 ohms, it's bad or at least something that needs to be checked out further. He's also got some other tips for troubleshooting this system. I know the links been posted before, but here it is again. Hope this helped and I'll give an update as soon as my newly used unit comes in.

patragz22
05-22-2008, 12:48 PM
was the brake problem ever resolved and what was the replaced??

tcshum
05-22-2008, 01:52 PM
Wow ... another major resurrection. I'm subbed to this thread and still watch it. Believe it or not, I still haven't fixed this problem. My car has been in storage until someone can figure this out. One day .... my SC will come to life again!;)

patragz22
05-23-2008, 01:50 AM
the reason I am asking and brought this thread back is my car does it do and did the same you did, I bled the lines several times and replaced calipers and checked the suspension and all good, next is the master, I have an extra one from a donor car and will try that soon.

tcshum
05-25-2008, 11:31 AM
I also have an abs assembly sitting in my garage, but haven't had time to put it in. Be sure to post up your results!


the reason I am asking and brought this thread back is my car does it do and did the same you did, I bled the lines several times and replaced calipers and checked the suspension and all good, next is the master, I have an extra one from a donor car and will try that soon.

sail7seas
05-25-2008, 08:44 PM
Wow ... another major resurrection. I'm subbed to this thread and still watch it. Believe it or not, I still haven't fixed this problem. My car has been in storage until someone can figure this out. One day .... my SC will come to life again!;)

I had a similar problem. Car pulled to right when I put on the brakes.
Then I did some front end suspension rebuild work w/alignment,
and car pulled to the Left when I put the brakes on.
The problem was NOT the brakes.
The problem was the steering rack. Which was replaced problem solved.
(had over a half inch of Play, found by a good mechanic)

patragz22
05-25-2008, 09:39 PM
whoa, another thing to consider..

tcshum
05-25-2008, 09:50 PM
I had a similar problem. Car pulled to right when I put on the brakes.
Then I did some front end suspension rebuild work w/alignment,
and car pulled to the Left when I put the brakes on.
The problem was NOT the brakes.
The problem was the steering rack. Which was replaced problem solved.
(had over a half inch of Play, found by a good mechanic)

Interesting thought. How do I check the steering rack?