Brake issues.

[muscle_Car1]

OK to start its a 1989 carbed, 4speed festiva.

The brakes went out on me thursday (mostly)
Brake pedal is soft then about 1in from bottom it locks up the front left & back right.

There are no leaks anywhere.
Replaced the master cylinder yesterday.
Attemped to bleed the brakes but there was no pressure to move any fluid.
Every once & a while I would get pressure.

So now im thinking its the proportioning valve.
Btw I still have the same 2 wheels that can brake if I floor it.
I'm kinda at a loss.

Ideas?????

[WmWatt]

Check for vacuum leaks in the booster? Just guessing.

[Safety Guy]

Weird.

The new MC should have solved your problem. I can only think of two things:

-bad proportioning valve
-defective MC

You know I'm no master mechanic, though.

One question: Did you bench bleed the MC before installation? I have no idea if not doing this would result in your problem.

Karl

[elcamino1]

Its got to be a bad proportion valve !!

[econoaddict]

First things I would do.
Bench bleed master, again if you have already done it just to make sure.
Install master cylinder and then open all 4 bleeders and let it just gravity bleed, it may take awhile so be patient.
If you get a pedal of any sort at this time, make sure bleeders are closed and then stomp hard on the pedal. If the porportioning valve is "off center" from the original problem this may help recenter it.
Bleed again normally and see what you have.

[Hot_Wheels]

we did bench bleed the master, we got the fluid almost clear, it still had some tiny bubbles but i dont think we could have gotten any more out cause they keept going back and fourth. at first i think we did have a issue with the booster, as we would pump the brake the idle would raise for a second, so we found the check valve, i think muscle_carl got that to free up one he blew on it (seems to stick), we didnt have any way to check for vaccum leaks on the brake booster, we did hit it with brake clean but i didnt hear the idle raise, as far as bleeding we had a lack of jack stands to do the correct procedure, we bled the passanger rear first, some time it would spirt out and then other times nothing came out, we then tried the driver side and same issue. we didnt bleed the front, we where concerned there maybe another issue due to the random spirts/no fluid coming out. he took it for a test drive and when slamming on the brakes passanger rear would lock up and driver fron but the other 2 had a delay

[Hot_Wheels]

p.s. good to here from you will!, it would be nice if you called so we would know your good and still havent sold your festiva!

[muscle_Car1]

The same basic conditions apply after swapping out the master as before, so I reply dont hope the master is bad. Any one have an extra proportioning valve, carby booster with vacuum line w/check valve handy? With my/alicias separation going down as it is, going to the inlaws to pick up anything is not a great option.

[doi_doi]

did you start the engine before you do bleeding?

[marinepolice03]

im almost positive i have the parts in st. anne, just call and tell me, or i have another place.

[drddan]

we bled the passanger rear first, some time it would spirt out and then other times nothing came out,

When bleeding brakes, it HAS to be total fluid coming out of the bleeders, or it ain't bled!

[FestYboy]

Kemp it can't be the proportioning "valve"... all that is is a block with predefined hole sizes for the rear drums to limit the pressure going back there. there are no moving parts. i'm betting on a blown LR wheel cyl. check those first, then rebleed your master on a bench and gravity bleed your proportioning block. then bleed car as normal (RR, LR, RF, LF).

[muscle_Car1]

So I went out to the car in the hopes that it mended itself, it didnt btw, but I did notice much more resistance wgen the car was not running vs when it was...

Lr is which side driver or passenger side. I redid the passengerside while changing the master

[TominMO]

Lr = left rear = driver's side.

[WmWatt]

I thought the proportioning valve was supposed to shut down one pair of wheels when either leaked, a safety feature, not just limit the pressure to the rear wheels? When I got a rust leak I didn't even notice until the line to one of the other pair leaked and I lost all pressure. From the original description of this problem I assumed there was a problem with one pair.