Wrong master cylinder - should I worry?

[RaeRae1]

Originally Posted by 72chevelleOhio

^ Thanks for that.....I was worried this thread might stay on topic....

yeah, that one was a dome scratcher.

Originally Posted by 72chevelleOhio

Anyways.....Is the "correct" MC from Napa actually the right one?

Yes, I am almost certain it is the right one. It matches in look and location of all the ports EXACTLY. Unfortunately, we put it in this weekend, and it is not good news. I can't explain why but after getting this one in and bleeding the sytem, the brakes are actually worse. The right rear seems to be the only one working (not positive on this). The right rear tire will lock up completely when you press the brakes and the whole car lurches. The brakes lights are still on as well. We pulled it back into the garage and bled the entire system a second time but still have the same results. Told my hubby we should just sell it... not going to of course but I am so frustrated right now I could scream. The only things left that have not been replaced are the distribution block and the proportioning valve. We have been given some things to try by someone on Mercury Forums and we will try that this week. I'll let you know what happens.

Oh, by the way - the exhaust sounds SWEEEEEET! Notes from heaven emitting from both pipes

One wierd thing that did happen - the first brake line that we bled with the new MC - the fluid came out red???? We bled the red fluid out but it did seem odd.

[MagicRat]

That one 'working' rear brake might have contaminated shoes.
I once got brake fluid on a set of shoes and it made that one brake extremely 'grabby' it would lock the tire before the other 3 brakes had a chance to work.
It does not take much spilled fluid to really affect them.

[RaeRae1]

Originally Posted by MagicRat

That one 'working' rear brake might have contaminated shoes.
I once got brake fluid on a set of shoes and it made that one brake extremely 'grabby' it would lock the tire before the other 3 brakes had a chance to work.
It does not take much spilled fluid to really affect them.

That sounds almost exactly like what it is doing and it is very possible with all this bleeding etc that it could have gotten fluid on the pad (except now I am scratching my head trying to figure how it got into the drum but.... If you are right, you will be my hero! I'll check on that first thing tonight. Although, not sure that would explain the brake light still being on. hmmmm.... Anyhow, I'll let you know.

I was told that the valve could be stuck and they gave me a theory on opening a bleeder, pushing the pedal quickly to the floor and monitoring if the brake light goes out. We will be doing that as well and if that doesn't work the valve is going to be taken out, cleaned and tried again.

Thank you!

Rae

[RaeRae1]

Tried the quick pedal stomp last night - didn't work. However, I looked in depth into what is involved in the distribution block. Think I found the problem in there. There is a valve inside the distribution block that allows even flow for front and rear - I am pretty sure the valve has moved forward and is stuck in that position allowing the fluid to only flow to the back brakes.

I will be taking it out, taking the valve out, cleaning it up and going from there.

[MagicRat]

Originally Posted by RaeRae1

Tried the quick pedal stomp last night - didn't work. However, I looked in depth into what is involved in the distribution block. Think I found the problem in there. There is a valve inside the distribution block that allows even flow for front and rear - I am pretty sure the valve has moved forward and is stuck in that position allowing the fluid to only flow to the back brakes.

I will be taking it out, taking the valve out, cleaning it up and going from there.

That's happened to me before, usually after stomping on the brakes when a brake line has burst due to rust.
Sometimes there is a reset 'pin' on the valve that you can pull/push to get the valve to center itself.

[RaeRae1]

Originally Posted by MagicRat

That's happened to me before, usually after stomping on the brakes when a brake line has burst due to rust.
Sometimes there is a reset 'pin' on the valve that you can pull/push to get the valve to center itself.

Yikes! Hence why I replaced all my lines, I really don't want to be cruising along and have a line burst.

Well, took out the distribution block - the valve is completely seized. I cannot even pry it out with pliers. These brakes are truely becoming the bain of my existance. I managed to find a "repro" of types - it isn't OEM by any means and I will still need to find some fittings that will make it work but it has the block and the proportioning valve all inclusive. It isn't too far off from the original and it was $100. I can apparently sell my current pieces for 100 each??

Anyhow, the new piece should be arriving this weekend. Wish me luck..... again....

Stupid brakes - sheesh - Wish everyone would just move out of my way so I wouldn't need them...

[bobss396]

Have you tried a part that fits other cars, like a Mustang, Torino, Maverick, Montego, Fairlane or Comet? I used to do that in a pinch and it usually was the exact part.

Bob

[bobss396]

Have you seen this yet?

http://www.cougarpartscatalog.com/adjpropvlv.html

[RaeRae1]

Thanks Bob. Yes, I have seen the West Coast Cougar Classics. On a first name basis with Don, the owner - ahahaha... We ended up ordering a part that is not a match but he told us it would work as long as we got some adapters. Well, the part came in today and after visiting 5 different auto stores, no luck. This system is cursed. Every roadblock we hit, we go around it only to find another one.

On a good side note - I have to say, there is one NAPA in our area that has some top notch people. Wayne (one of the employees), after being baffled that we he could not find the right adapters, helped us get the valve out of the old one. We are gonig to just rebuild it and try reusing it. I hope... I mean I REALLY hope this works.

Thanks!

[bobss396]

Did it work? Just curious to see if you slayed the master cylinder dragon.

From my experience with old cars, the more you digress from stock or repro parts, the more trouble you're going to be having.

Bob

[RaeRae1]

Originally Posted by bobss396

Did it work? Just curious to see if you slayed the master cylinder dragon.

From my experience with old cars, the more you digress from stock or repro parts, the more trouble you're going to be having.

Bob

Well Bob, unfortunately the system is STILL FUBAR. We keep scratching our heads. The distribution block (the original, we didn't end up using the other one) and the valve seem to be working fine. The brake light is off and the valve seemed to slide back and forth easily. Unfortunately the front system still seems to be off. A new proportioning valve is on its way (one that is adjustable). That will be the only thing on the system that is not repro or original/rebuilt.

Here is what is next on the plan: We are going to try gravity bleeding the calipers and also installing the new proportioning valve. If those two things do not work, then it is back to square one. We will then remove (AGAIN!) the master cylinder and inspect it carefully. Someone suggested that we may have pushed the valve in too far when bench bleeding and it may be stuck. That would make some sense because it is a two valve system and if the front one were stuck... the front brakes would not work right.

Of course, I am just avoiding this because in order to get the master cylinder off, I have to take off (or at least loosen) the booster. And that job is like sticking a fork in my eye.... it is miserable. But... we do what we gotta do for our hobbies right?

[bobss396]

I feel your pain. Gravity bleeding is ok, but only gets you so far. One key question, are the front caliper brake bleeders facing upward? I'd hate to see them on the wrong side, not sure if it is possible on the Cougar though, I had to mention it.

And it IS a disc brake master, the front brake reservoir is noticeably bigger. Do you have new brake hoses installed?

I bench bleed my masters by hand, I don't think you have enough power in your hand to damage the internal cups. I've seen old masters damaged by in-the-car bleeding. Helpers who don't know any better tend to stomp or push the pedal too far. I tend to doubt that your master has been damaged.

Once you have it out (AGAIN!), give it a bench bleeding just for old time's sake. If both ports produce pressure, the master should be fine. I bleed mine this way: I clamp the master in a bench vise. Fill it up with brake fluid. With the cover off, hold two fingers over the brake line ports, push the rod (or use a screw driver) in and out. You will see bubbles come up to the surface from the bottom of the reservoirs. Keep doing the in-out thing until you see the bubbles stop. Your master is bled. Fill it up, put the cap on and avoid pushing the rod until you install it.

Is the brake pedal rod adjustable, or do you just have the one that pokes out of the vacuum booster?

Ok, install the master, tighten up the lines. If you want to, you can do the gravity bleed thing, which won't get you very far from my experience with it.

From scratch, bleed the whole works, start with the right rear, go to the left rear. Whoever is the pedal-person, have them push it far enough to get a steady stream, but not go to the stop with the pedal.

Crack the bleeder about a 1/4 turn (got a bleeder wrench?), tell the pedal-person "down" , they will push the pedal down, then say "down". You close the bleeder, tell them "up" they release the pedal and say "up" back to you. This lets everyone know what to do. If for any reason you drop the wrench and the bleeder is open, tell them to "stay down". There is a professional short cut that I won't share with you right now, stick to the basics.

After each wheel, top off the master, you can lay the cover on loose. 3 or 4 shots per rear should take care of it.

Now go to the right front, the drill is the same, you might want to crack it even less than a 1/4 turn. Tell the pedal person not to bottom it out again. Within 3-4 pushes, the fluid should be almost clear with no air. Fill the master, move to the left front, do the same thing. Fill the master.

The pedal should be pretty good by now. The pedal person can manually push the front pads out if the system has no air. Top off the fluid, clamp down the cover, push the pads out under power.

If you want, go around the whole car and give each corner one shot at each bleeder. I used to do this all the time. You should crack each bleeder less than a 1/4 turn, the pedal-person has to be informed to go easy on the pedal.

If all is well, you should have brakes that work. I'm not sold on the adjustable proportioning valve idea, I think that it is a crutch for the bigger problem that you've been dealing with, you're just not sure what it is yet. I've only used them on stock cars and never on a street car.

Good luck, hope this helps.

Bob

[70elko]

if you run into a fitting problem with the hydraulic lines you can always go to a good radiator shop and they can custom build you a hose with fittings or add length or different fittings to make your application work if they are steel lines you could buy most things from autozone but if they dont have the line a steel braided line wouldnt hurt the only problem with that is the flexibility but dont have to worry about pinching the steel line

[RaeRae1]

Originally Posted by bobss396

I feel your pain. Gravity bleeding is ok, but only gets you so far. One key question, are the front caliper brake bleeders facing upward? I'd hate to see them on the wrong side, not sure if it is possible on the Cougar though, I had to mention it.

No problem in mentioning any ideas. I think it is possible with the cougar to put them on the wrong sides but I am almost certain they are on the right sides. The bleeders are located toward the top of the calipers with the bleeders facing the back of the car.

Originally Posted by bobss396

And it IS a disc brake master, the front brake reservoir is noticeably bigger. Do you have new brake hoses installed?

Yes, it is a front disc, rear drum master cylinder, the front reservoir is definitely bigger (longer) than the rear. All the lines and the hoses are new, only things that are not new on the system are the proportioning valve and the distribution block. Even the booster is a rebuilt/restored one.

Originally Posted by bobss396

I bench bleed my masters by hand, I don't think you have enough power in your hand to damage the internal cups. I've seen old masters damaged by in-the-car bleeding. Helpers who don't know any better tend to stomp or push the pedal too far. I tend to doubt that your master has been damaged.

I hope you are right. Still good to check it. Since it has a two part valve, I am thinking there may be something wrong with the front part, perhaps the spring, or perhaps it was put together wrong at the factory... who knows. But regardless, I will definitely be taking it apart if I take it off, just to make sure.

Originally Posted by bobss396

Once you have it out (AGAIN!), give it a bench bleeding just for old time's sake. If both ports produce pressure, the master should be fine. I bleed mine this way: I clamp the master in a bench vise. Fill it up with brake fluid. With the cover off, hold two fingers over the brake line ports, push the rod (or use a screw driver) in and out. You will see bubbles come up to the surface from the bottom of the reservoirs. Keep doing the in-out thing until you see the bubbles stop. Your master is bled. Fill it up, put the cap on and avoid pushing the rod until you install it.

Great plan. I will definitely do that. I have plugs though, should I just use those instead of plugging the ports with my fingers?

Originally Posted by bobss396

Is the brake pedal rod adjustable, or do you just have the one that pokes out of the vacuum booster?

That is one other school of thought. The cougar has an adjustable rod that goes from the booster to the MC. I failed to measure it, and I am not certain it is the right measurement . It is only a small screw at the end and from what I was reading in the manual it is a bit confusing to judge just where the measurement needs to be. I'll have to look at it closer, and see if I can figure out how to measure it. I don't know if this would cause the severe problems we are having though. I was under the impression that if this was not adjusted properly it only caused minor problems.

Originally Posted by bobss396

Ok, install the master, tighten up the lines. If you want to, you can do the gravity bleed thing, which won't get you very far from my experience with it.

From scratch, bleed the whole works, start with the right rear, go to the left rear. Whoever is the pedal-person, have them push it far enough to get a steady stream, but not go to the stop with the pedal.

Crack the bleeder about a 1/4 turn (got a bleeder wrench?), tell the pedal-person "down" , they will push the pedal down, then say "down". You close the bleeder, tell them "up" they release the pedal and say "up" back to you. This lets everyone know what to do. If for any reason you drop the wrench and the bleeder is open, tell them to "stay down". There is a professional short cut that I won't share with you right now, stick to the basics.

Hahaha - now you have me curious.

Originally Posted by bobss396

After each wheel, top off the master, you can lay the cover on loose. 3 or 4 shots per rear should take care of it.

Now go to the right front, the drill is the same, you might want to crack it even less than a 1/4 turn. Tell the pedal person not to bottom it out again. Within 3-4 pushes, the fluid should be almost clear with no air. Fill the master, move to the left front, do the same thing. Fill the master.

The pedal should be pretty good by now. The pedal person can manually push the front pads out if the system has no air. Top off the fluid, clamp down the cover, push the pads out under power.

If you want, go around the whole car and give each corner one shot at each bleeder. I used to do this all the time. You should crack each bleeder less than a 1/4 turn, the pedal-person has to be informed to go easy on the pedal.

If all is well, you should have brakes that work. I'm not sold on the adjustable proportioning valve idea, I think that it is a crutch for the bigger problem that you've been dealing with, you're just not sure what it is yet. I've only used them on stock cars and never on a street car.

Good luck, hope this helps.

Bob

Thanks a ton Bob. A lot of the bleeding procedure we already had down, since we have done it to SOOOO many of our cars previously. We have been doing our own brake work for over 20 years now. But every bit of information helps. And I did learn some new ideas and ways to do it. Your post was fantastic and extremely easy to read. It should be made a sticky!!

Every part is new, so now we are so stuck as to where to turn. That is why I think we need to start from scratch with the MC and go the rounds, one more time. My biggest disappointment is that the snow is coming, and I really really really wanted to be able to cruise in my vert before it did. I think that dream may not be in the realm of reality for this summer. *sigh*. But, this car and these brakes WILL NOT WIN.

I know, how about I buy you a plane ticket, a 12 pack of Pabst (or other favorite beer) and you come out here to help!

[bobss396]

I'm glad your calipers are on straight. I've seen people try to bleed brakes with the bleeders on the BOTTOM of the calipers.

I really don't recommend taking apart a master cylinder unless you have new cups on hand, you'd need the instructions that do come with a rebuild kit. if everything else fails, it is an option.

If you do have those plastic cups that come with the master, use them. I worked with a guy that made up a set from fittings and brake line which he crimped and brazed up. The cups should seal, if you keep getting bubbles coming up, then you know they're not sealing 100%. It could be a 2-person job without the cups. I'm so used to doing it from doing it for a living!

The adjustable rod could be very well the root of your problems! I ran into one when I was first in the brake business on a '66 Chevy, the brakes wouldn't release once they were applied, luckily I worked with an old timer that knew IMMEDIATELY what happened. There has to be a certain amount of free-play. Once the fluid is cycled a few times it heats up and expands just enough to jam up the system. Too much free-play might be your problem, work on getting the right info on measuring. If you need me to look at an old Chiltons, send me a PM. I'd say that the tolerance is something like +/- 1/16", which you can measure with a good scale. I'm not sure if the front brakes apply first, which might be the case on the disc brake master.

The trick I mentioned is an easy one. When you bleed brakes, open the bleeder only once. When the pedal-person does the "up" thing, just hold one finger over the opening. On the "down" stroke, remove the finger. It saves a lot of open-close operations and wrench dropping.

I'm glad to help and have a lot of Ford experience between my past fleet of Mustamge, Fairlanes, Cougars and Falcons.

I believe that you have a "stupid" problem on your hands. Not that anyone is stupid, but there is just one confounding thing that you have to find by ruling out all the other possibilities. You'll beat it yet, and maybe the snow!

I'd like to come out, but am busy with work and home projects of my own. No car fun for me. The 12 pack of Pabst is however enticing.

Bob