brake fluid leak

super16g

Registered User
I have a 89 SC that just developed a brake fluid leak.I traced the leak to this thing that looks like a metal box about 4 inches in length and is located on the drivers side way down in the engine bay.Almost looks like it is sitting on the frame.It has some skinny metal brake lines running in and out of it.I know this description is vague but do any of you guys know what this thing is called or have a part #??Im sick of adding brake fluid every day..Thanks...
 
If so, that is the "Proportioning Valve".
SOMETIMES, it leaks from farther above (From the Pressure Switch) and trickles down those brake lines onto the valve too. Make sure that it IS the valve leaking. Do a search on Proportioning Valve to find a cheap place to get one..
 
Yep,,thats it..Thanks so much..How hard is it to change one of these valves??Easier from the top or bottom??
 
I'd do it from bottom on ramps. Might make sure that the valve is NOT under extreme pressure. Think only the Accumulator is. You will need to bleed the brakes when you are done as I'm sure taking that off will let air into the system. The rears MUST be bled with the KEY in the ON posistion (Not running). This allows power to the ABS to turn on. Fronts don't need to have key on.
 
I dont think that the brakes will need to be bleed when you change the porportioning valve. I had to replace mine awile back and I never bleed the brakes. Maybe I just got lucky?

Shane
 
You should bleed the brakes any time you 'open up' a closed hydraulic system. Air can go into the lines, also the new valve isn't full if brake fluid so it will have air bubbles in it as well if you dont bleed them.
 
Hey guys,,Does anyone know where I can buy one of these things??I went to Ford today and they said the part is discontinued..They also said they were showing non in the country!!!Anyone aftermarket units out there??If not,,anyone selling one that doesnt leak??Thanks...
 
Got my "Pressure Warning Switch" from: http://www.buy-gm-parts.com/ off a 1988 Buick Reatta w/ ABS. (Another discontinued part for Teves Mark II System for my 1990). Not sure if the "Proportioning Valve" would be the same thing on that car as on ours though...:confused:

Try a search as I recall someone fixing theirs with just an O-Ring or plastic washer from the parts store...but sometimes there are shot internally and the O-Ring trick will not help at all.
 
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same boat

looking for that sensor that screws into the proportioning block if any clues let me know. can that sensor be by-passed and plugged?? any way a tough part to track down. almost as bad as the little dis module shortage awhile back. thank todd..
 
anlo said:
looking for that sensor that screws into the proportioning block if any clues let me know. can that sensor be by-passed and plugged?? any way a tough part to track down. almost as bad as the little dis module shortage awhile back. thank todd..

You probably can still get them at Ford. Thats where I got mine a few years ago.

Shane
 
make sure its the proportioning valve.
Spray with Brake Cleaner and then check it to see where the drip is comming from. most likey its the valve but always good to make sure. i just did mine a few days ago. takes about 10 mins in my driveway :)
i didnt bleed my brakes and they seem perfectly fine. i had the valve unpluged in my driveway for about 6 days to draining into a bucket
 
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For The Dumbasses That Work On Thier Own Brakes

PLEASE BLEED YOUR BRAKES ANY TIME YOU OPEN OR CRACK ANY PART OF YOUR BRAKE SYSTEM. KNOW WHAT YOU ARE DOING I HAVE READ SOME OF THE POSTED REMARKS ON HERE AND IT SCARES THE ~~~~~ OUT OF ME THAT YOU GUYS ARE ON THE ROAD. QUICK35TH YOU ARE ARE A MORON!!!!!!!!!!!!!1:mad: :mad: :mad: :eek: :eek:
 
For The Dumbasses That Work On Thier Own Brakes

PLEASE BLEED YOUR BRAKES ANY TIME YOU OPEN OR CRACK ANY PART OF YOUR BRAKE SYSTEM. KNOW WHAT YOU ARE DOING, I HAVE READ SOME OF THE POSTED REMARKS ON HERE AND IT SCARES THE ~~~~~ OUT OF ME THAT YOU GUYS ARE ON THE ROAD. QUICK35TH YOU ARE ARE A MORON!!!!!!!!!!!!!:mad: :mad: :mad: :eek: :eek:
 
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