Still Having Brake Issues

[mikester]

Just a little update for you folks. Plus maybe someone can point me in the right direction.

Since my first thread I took most of the stuff apart. I found out that I have the right size pin in the booster. I thought that was a good thing. LOL
I took the original master that I just bought, put it in the vise and bench bled it after I put in two inverted flare plugs. The rear section of the reservoir looked good. The section nearest the booster kept getting small bubbles. Not all of them as I was bleeding it, some would pop up when I stopped. I figured maybe I nicked the rubber cup inside the master the first time I bled it manually in the car.
I had another new Delco master that I got from rockauto. I planned on sending it back for a refund. At this point I figured I would try it since I had it in the garage. Stuck it in the vice, bench bled it and it looked fine. Put it in the car and I figured I was good to go.
While I had everything out I also pulled the proportioning valve. This was new from Inline Tube. I pulled it to install the plastic plug that prevents the rod from pegging at one end or the other. I got the rod centered after I pulled it out, screwed the plug in and put it back on the frame.
Now comes the strange crap thats making me nuts.
Im using a Mighty Vac air bleeder. The one that sucks the fluid out of the bleeder screws. I used the same one on the wagon and it worked fine.
I went to the rear. Right side seemed okay but there was a lot of air. Left side was the same way.
Went to the right front. Same deal. Lots of bubbles. Finished both sides and did it all over again. Same again. Lots of air.
Now Im wondering where the hell all the air thats in the lines is coming from.
I take the plug out of the proportioning valve and put the switch back in. Again, lots of air.
I checked every fitting. Nothing leaking anywhere in the system. Not even damp threads on any fitting.
I called MalibuDave since hes up on brake systems. Great guy to talk to and he went through everything I did. Hes thinking maybe I got a bad proportioning valve.
When I clamped the lines the pedal was hard, about a quarter of the way down. Now the pedal is still on the soft side, about halfway down.
Im stuck. Im pissed. Ive torn this crap apart too many times and I still dont have the issue fixed.
Im probably going to bits the bullet and get another new booster. Its the only thing I havent replaced. Two masters bad ? Not likely. Im calling Inline tomorrow and Im pushing for a new prop valve.
New calipers, rubber lines, wheel cylinders. Back brakes are adjusted right. They werent the first time but now they are for sure.The last time I bled it the fluid was filled with fine bubbles. I wondered if the air was getting in through the bleeder threads.
Anyone got any other ideas ? MalibuDave suggested posting another thread so here it is. Anyone else ever have a crazy problem like this ?

.

 

[TexasT]

If you see bubbles, keep bleeding. Bubbles mean air and a spongy pedal. You might need another bottle of brake fluid. I would like to recommend a helper and the press, hold and release with said helper that knows the drill. Sucking isn't the same as pushing that fluid down the lines. Especially, as it seems, on these older vehicles.

I think the pushing helps clear the lines of the rust n crudge that develops and seems to "catch the air and hold it in the line. That is just a theory of mine. We did a car a couple yrs back where I had to remove the bleeders on the rear several times to clean them out and keep bleeding to get it to flow good.

You clamped the lines so in theory the mc is working. If you are still getting bubbles, even those small ones, you still have air in the mc. Keep bleeding. I like to do it on the car with the plugs. This eliminates the , I tilted it and jostled it around and got some more air in during the install onto the car. Then after the on car bleed, the lines can be installed, reservoir topped off and it is on to the rear pass side bleed. You are bleeding mc, pass rear, driver rear, pass front and last driver front right?

Be patient with the bleed, not jerky motion or quick with the pedal. Nice even slow strokes to entice that air out and not introduce more. and a clear tube and bottle(I used to used a glass mayo jar but not sure where it went over the yrs so now it is a plastic clear mayo jar) so I can see the bubbles. Each of my children learned the pedal procedure over the years, but a wife or Buddy(or buddy's wife i guess), can do the pedal.

It isn't a race. Take your time and get ALL the air out. Even those little bubbles. They are air too.

 

[mikester]

If you see bubbles, keep bleeding. Bubbles mean air and a spongy pedal. You might need another bottle of brake fluid. I would like to recommend a helper and the press, hold and release with said helper that knows the drill. Sucking isn't the same as pushing that fluid down the lines. Especially, as it seems, on these older vehicles.

I think the pushing helps clear the lines of the rust n crudge that develops and seems to "catch the air and hold it in the line. That is just a theory of mine. We did a car a couple yrs back where I had to remove the bleeders on the rear several times to clean them out and keep bleeding to get it to flow good.

You clamped the lines so in theory the mc is working. If you are still getting bubbles, even those small ones, you still have air in the mc. Keep bleeding. I like to do it on the car with the plugs. This eliminates the , I tilted it and jostled it around and got some more air in during the install onto the car. Then after the on car bleed, the lines can be installed, reservoir topped off and it is on to the rear pass side bleed. You are bleeding mc, pass rear, driver rear, pass front and last driver front right?

Be patient with the bleed, not jerky motion or quick with the pedal. Nice even slow strokes to entice that air out and not introduce more. and a clear tube and bottle(I used to used a glass mayo jar but not sure where it went over the yrs so now it is a plastic clear mayo jar) so I can see the bubbles. Each of my children learned the pedal procedure over the years, but a wife or Buddy(or buddy's wife i guess), can do the pedal.

It isn't a race. Take your time and get ALL the air out. Even those little bubbles. They are air too.

Ive bled this system more times than I can count at this point. Im on my 4th qt of brake fluid. The first time around I bled it with the air bleeder and then switched to the old fashioned way and still had the issue. Thats why I took it all apart AGAIN and replaced the master with another new one that I planned on sending back. Its a Delco.
Theres nothing in the lines as far as rust. The lines from front to rear are SS from Classic Tube. All new rubber hoses too. Every parts new except the booster which was also new when I put it on. The cars never seen the road since then.
And if you reread my post you'll see that I bench bled the master and there was no air in it when I was finished. I bled the right rear, left rear, right front, left front. Not the first time in my life that Ive done brakes but the first time Ive had an issue like this.
This is why Im reaching out to the guys on the forum. Im totally stumped.

 

[pontiacgp]

are all the bleeders at the top of the caliper or wheel cylinder?

 

[Clarmo]

Just a little update for you folks. Plus maybe someone can point me in the right direction.
When I clamped the lines the pedal was hard, about a quarter of the way down. Now the pedal is still on the soft side, about halfway down.

I told you to do this and so did Malibu Dave
You say the pedal was hard when clamped...now is still on the soft side. What did you do? Remove the clamps? Front? Rear?
Another thing to look at is the Parking brake. If the cables are too tight...and then you adjust your brakes...this will give you a low pedal too. Remove the horizontal bar between the shoes, re-adjust the brakes and try the pedal.

 

[mikester]

are all the bleeders at the top of the caliper or wheel cylinder?

Of course.

 

[pontiacgp]

good luck in finding the problem

 

[mikester]

I told you to do this and so did Malibu Dave
You say the pedal was hard when clamped...now is still on the soft side. What did you do? Remove the clamps? Front? Rear?
Another thing to look at is the Parking brake. If the cables are too tight...and then you adjust your brakes...this will give you a low pedal too. Remove the horizontal bar between the shoes, re-adjust the brakes and try the pedal.

Ive had multiple phone conversations with Malibu Dave. At this point hes stumped too.
As far as the parking brake, the cables not hooked up yet.
Taking out the bar might be an issue. Its a Ford drum setup. Not sure how I could get the right adjustment without the bar being there. Wouldnt removing it make the top go in too far ?

 

[mikester]

good luck in finding the problem

Thanks. This is getting really frustrating.

 

[pontiacgp]

Thanks. This is getting really frustrating.

I don't see what the problem could be because of course you have done everything correctly