[bamakodaker]

Hello,

Continuing in the saga of brake problems with my 2005 Ford Focus 2.0. Changed pads, rotors, calipers, PCV valve and hose -
now going to master brake cylinder and booster.

Am I missing something? I don't find any discussion here about changing a brake booster? Surely those have been changed out but I do not find it here. I need to change mine - any pointers?

bamakodaker

 

[sailor]

You may not find many prev. posts, as the booster doesn't often cause problems.

I'm guessing you mean the booster hose & check valve, NOT the "PCV" hose...

Please add some commentary on the issue that started the "saga", as well as the current symptoms, so our members can take some "educated" guesses as to what may help.

Thanks & Good Luck!

 

[bamakodaker]

It seems all my older posts have gone away. That was where the saga was played out - I thought!
Where could I find info about changing the booster hose and check valve? Are those the words that a parts counter would understand if I wanted to buy those?

bamakodaker

 

[elsolo]

Yep, any parts store employee should know what a vacuum brake booster check valve is.

It's the plastic fitting that is stuck prominently on the front side of the brake booster, and has the one and only vacuum hose attached to it.

I still think it is more likely the master cylinder's internal check valve.

 

[a_2000_se]

I'm curious what your original saga problem was/is. I just started getting brake problems myself.

1) grinding noise on the front passenger side at low speed when stopping just before coming to a stop. Brake pads are almost new and don't have uneven wear - I had a new spare caliper that I replaced the old one with with no change.

2) brakes are somewhat a little 'mushy' when car is first started after being off for a period of time.

I haven't looked at anything yet but I think it kinda sounds like a vacuum related - no fluid loss. Does any of this match your problem?

 

[bamakodaker]

Well great! I have the master cylinder off. I had bought a reman unit then decided to not use it but get a new one. The new one does not have a reservoir. No where have I noticed the 'make sure your master cylinder comes with the reservoir'! I can NOT get the reservoir off! Any suggestions? I'm loosing daylight trying to figure this out. I don't want to break the reservoir.
Thanks for any help.
bamakodaker

 

[amc49]

The crux of the problem. The rubber bushings get hard and then you break reservoir trying to free it, the reason why most buy master with reservoir already installed.

Since turning it in for core you might try throwing it in very hot water but remember the plastic will get weaker just like rubber. The rubber should give first though. The rubber often not reuseable after disassembly...............Hope you got new rubber. All those parts really only meant to be used once, the aftermarket is super cheaping out and dumping the problem on end user. Similar to not providing power steering with pulley anymore. Max buck paid for minimum part.

 

[bamakodaker]

a_2000_se
Mushy sounds like brake fluid problem. Two people flushing the system works GREAT! I'd flush the brake lines, making sure you don't get air in the lines. Good luck. Stay safe!

 

[bamakodaker]

The brake saga - - -
The front right brake would become lightly engaged after I started the driving the first time of the day. Sometimes it's not noticeable until I started to hear an extra roar over the road noise. To check it I'd tap the brakes and the pedal would not go down. The brake was dragging, causing the parts to get hot, expand and cause the brakes to come on more. I could tap the brakes but most times that would NOT make any difference. I'd have to park for about 10 - 15 minutes. Things would cool down and I could drive the rest of the day with no problems.
Other times I'd know the brake was dragging because I'd get a vibration in the steering wheel. It would easily be diagnosed as bad rotors. However - stop for 10 - 15 minutes and there would be no more problems for the day. Put on the brakes and it would be like normal, therefore there was nothing wrong with the brake rotor.

All of this causes multiple problems but NO ONE has figured this out! It is a problem that I believe plagues a LOT of Focus!

FIRST - go online and look at how many people have replaced steering wheel columns on Focus'. The replace it because the steering wheel becomes loose. They think the column is bad. My steering wheel started to get loose, it would wobble on the column. I wanted to research the problem. Early in a search about the problem I found this:
http://www.steeringcolumnservices.com/
There is an upper bearing that tends to cause this problem. []The shaft can slip out of place during a repair and then the bearing becomes unseated and causes this problem. []
===========
I was ready to order a column, about $400 I think.
I wanted to research more. I ran across the following:
http://forums.focaljet.com/mk-i-interior-modifications/531338-steering-wheel-replacement-how.html
or
http://www.focusfanatics.com/forum/showthread.php?t=99259
or another that I can't find right now that was about changing steering wheels.
As I pulled in to my driveway at the end of a work period (I was starting four days off) the steering wheel skipped - I turned the steering wheel but the tires did not turn! I push the steering wheel down, hoping to engage the steering wheel column teeth and it worked. Wow, thank you Lord!
Since I'd done that research I decided to take things apart to see what was wrong. I wanted to know if I needed to replace the column. I'd disconnected the battery and got down to taking off the airbag so I could see the steering wheel bolt. It was LOOSE! And I don't mean a little! I turned it a LONG time with my fingers! I got the proper tool and tightened it up and BINGO!!!! NO MORE looseness in the steering wheel!
This happened 2 or 3 more times UNTIL I got the brakes fixed and the vibration stopped! Did you catch that? I stopped the brake vibration problem and I had NO MORE loose steering wheel!

BRAKES - It is my opinion no one is sure what causes the brake problem - brakes that start dragging. It is a COMMON problem. Search and Focus dragging brake problem seems to ALWAYS be at the front right!
A first problem is associated with the PCV hose on the Duratec engine. It's hidden under the intake manifold!! I replaced the hose (and the PCV) because it had gone bad just like you'll see online during a search about that! I can't remember exactly but it was something about a vacuum leak affecting something which made the brake engage.
Everything was within the front brakes so that's where I replaced parts. I believe I replaced the rotors and pads but after a while the brake vibration came back. I then replaced the front brake calipers AND brake lines. With the pads dragging a LOT of heat builds up. Brake lines are really two tubes in one. That inner liner/tube may buckle inward and not let fluid flow thru like it should. I think I also replaced the master cylinder during this time.
The vibration disappeared!

WHAT EVER ALLOWS THE BRAKE PROBLEMS TO START CAUSES ALL THESE PROBLEMS.

Here I am one year later - - my front right brake pad is gone and I'm getting gouges in the rotor!! The other brake pad has very little wear on it.
I want to replace ALL the vacuum hoses - especially the booster hose and vacuum brake booster check valve. I'm not sure but I may consider replacing the caliper again.

Has anyone found a solution??

Much thanks,
bamakodaker

 

[a_2000_se]

Glad you're still at it but sorry to hear you still have the problem.

I'm looking at "The front RIGHT" brake problem too. It also has been over a year. And I've been leaning toward a booster/check valve for the last year also since over this time PADS/Caliper/disc/wheel bearing were replaced.

My symptoms are still pretty consistent -

- The grinding noise(like when pads are too far worn, but they aren't) occurs when braking at the speed just before the car comes to a complete stop.

- There is no grinding noise if the brakes aren't applied - turning, slow speed, high speed or coasting. No noise.

- If you press hard on the pedal when the noise occurs, the noise goes away but just temporarily.

- The problem happens with much more frequency in HOT weather than cold weather.

- The brakes seem to fade when driven after a lot of stop and go city traffic. And it almost feels like there is slippage at times - like the tire was on ice, in the middle of summer on a sunny dry day (no ice or liquid).

- At times it feels like the car has the feel of brand 'NEW' brakes, not a car with 175k miles.

The only thing I haven't changed is booster related/vacuum related and brake lines. Hope this helps you because you've helped me with what you've found out so far.

 

[amc49]

Booster check valves affect the pedal-it will get HARDER with a leak, not mushy. The check valve cannot make a brake drag. The shaft coming out of booster has an adjustable tip that MUST be set correctly or will hold brake on slightly to eventually drag. I set mine for maybe .030" play before the M/C begins to move. You should never overlook setting that even though virtually no paperwork on the planet mentions it. All M/C pistons end up in different full-OFF locations, even same model part. The rebuilder sets the shaft to a range that to them should work but look how competent they are, they cannot even tighten bolts without breaking things. Last one I set turned very easy, I loctited it in place with removeable blue loctite.

 

[bamakodaker]

elsolo - you say it could be master cylinder's internal check valve. So I should replace master cylinder again? Are there problems with master cylinders? I'm guessing the master cylinder I put in last year was a reman unit.

 

[amc49]

LOL, the ENTIRE master cylinder is a check valve................actually at least two.

 

[bamakodaker]

A comedian! I love it! I'm driving a car with grinding brakes because no one knows what the problem is. I'm seeking help because my off days are the days to WORK on my car, not research!
So when someone suggested it is more likely the master cylinder's internal check valve, they really meant I should replace the entire master cylinder?
As I said in my saga - I had front, right brake problems - new rotors and pads didn't solve it. New calipers and hoses did solve it - for almost a year (probably a little over 10 months). NOW it's back again!!
WHAT is causing the brake to engage/drag?? What is causing extra pressure to go to that side?
bamakodaker

 

[a_2000_se]

Do these cars have a proportioning valve? Front-to-Rear/Left-to-Right?

 

[bamakodaker]

a_2000_se - proportioning valve - nightmare! At least in my search!! A Google search indicates yes. A link goes to AutoPartsExpress but when you search on their site in goes to a deadend link - "Error 405 not allowed". There is something in FixYa where someone is having very close to the EXACT problem we have and the answerer reminds them the proper way to bleed brakes but if they are still having the same problem then they 'need to bleed the proportioning valve'. NOWHERE have I found that mentioned before. But if you look through that answerers responses to others questions it seem he feels ALL problems involve the proportioning valve!
Now that I've vented - - from early in this problem I've wondered about a proportioning valve. SOMETHING is activating the front right brake. I'm trying to chase info on that valve! Share if you learn something please!
bamakodaker

 

[bamakodaker]

from FF Archives -
http://www.focusfanatics.com/forum/archive/index.php?t-158403.html
This guy writes of brake problems. Says he discovered his front left smelling like something burning. He'd replaced calipers and master cylinder, then flex hoses.
Took it to a repair shop. Repair guy said diaphragm or the booster.
'He lifted the car up, took the wheels off, set it in park and let the rotors spin.
They locked up after applying pressure to the brake once. He tried to turn them and they wouldn't turn.
He then disconnected the booster while the car was running.. the rotors start to spin. Wow.
He reconnects the booster and the rotors lock up. Double wow.'

The problem I have with this is his write up mentions 'rotorS', as in BOTH. I'm having continued problems on ONE side. After a year my front right pad is gone. My front left has very little wear.
This makes me question it being the booster.

At the following page
http://www.focusfanatics.com/forum/showthread.php?t=298556
- a little over 1/2 way down is a response from - amc49 - where he writes -
'You are correct 80% of braking done by the fronts. These have no proportioning valving, only valves that limit pressure buildup to the back, an effort to reduce rear lockup."
Further down he writes -
'No proportioning valve per se but the small cylinders screwed into two ports of M/C are pressure limiting valves, they lower pressure to rear brakes to help control lockup in the rear. That's on non-ABS car like mine, sometimes those limiters can be on the ABS unit.'

I had the problem. Changed master cylinder, rotors, calipers, hoses, pads. 10 months later the problem returns. Now, it could be my new caliper stuck once and caused the problem. I'm guessing here but if it stuck and the pad was dragging, it would heat up and come on more causing more heat which could affect the flex line so that it is bad again. I'm just guessing but - what's left if there is no proportioning valve??

I'm going to get booster check valve (I didn't change it last time), new flex hoses (since these have gotten hot), new rotors (since I waited to long and rotors are gouged), new calipers (in case they were sticking) and pads. IF a dragging brake becomes a problem again after that then I'll replace booster.

I don't know anything else to do.

 

[amc49]

Whoopee, I'm famous Ma!

Look here, you can change change boosters all you want and I 100% guarantee it will not affect a dragging caliper. Ditto on the booster check valve. Change the booster and you may make the problem much worse though. Your repair shop guy quoted there is incompetent or a ripoff 'artiste', not the booster at all rather the setting of the shaft coming out of it and no need for new part at all. The shaft if not set right pushes M/C out slightly to block compensation port(s)............You reset that every time the booster is changed, the adjuster is self locking but some loosen with use and re-set and loctite and fixed. That kind of knowledge disappeared with the onset of ADD in schools. $25 job but you're a stupid mech if you don't get $200 for booster instead and another $50 in profit there. Glory be..........that was hard. There is a vent check inside the booster that could be bad as well but so rare that I don't even consider it, suffice to say the booster would be brake full on all the time if bad. Not the case here.

You need to check the M/C for the lineup of those two compensation port holes, one could be clear at full retract of the piston and one might not be depending on the M/C casting quality. Holes may be corrosion clogged and common. The holes vent fluid when brake is full off to make up for temperature changes. If blocked, whichever one is will begin to pressure buildup until brake begins to stay on, that makes more heat and worse. A vicious cycle there. After that I ALWAYS (never ignore it!) check that shaft setting if booster is changed, you need slight looseness there to guarantee full retract on the M/C piston so that it comes back to clear the compensation ports. I use like .030" clearance there. You have to pull booster and M/C to set that clearance.

Diagonally split brakes here, one front and opposite rear are tied together and the opposite pair the same. Meaning any M/C issue like comp port can appear to be a single front only even though one front and one rear in same hydraulic system. The rear brakes take more motion to activate to let them come on later than fronts. So if a compensation port blocked it will show only in a front, not a rear.

Other than that, ONE CALIPER and one only dragging, the caliper is sticking at slider pins, dust seal bad to let moisture inside to corrode piston so seal warp does not retract it or flex line degraded inside to let rubber come loose that can sometimes stick to create a one way valve there. Even minor differences there, if caliper has one piston only then dragging pins will show as one pad worn worse than other on same caliper, if corrosion inside then BOTH pads can be dead. If they use lots of salt on roads in winter sticking caliper can be a yearly issue.......

True proportioning valves are only for front /rear split systems and cannot work on diagonally split like these so toss all that info as inapplicable to you. If there WERE any type of proportioning going on you'd have to have TWO of them, one for each front/rear there. Haven't seen any car do that yet.

 

[bamakodaker]

amc49 - VERY nicely written and informative note!!
I had to read it again, yet slower. This is FANTASTIC! I've been looking at this problem over a year. I've found MANY people with the 'one front wheel brake problem' but your write up seems to offer FAR more hope than I've ever seen! KUDOS!

Could it be that the nut locking the booster shaft setting has come loose on all these cars with one front brake problem?

According to your description I'm thinking this could really be my problem. I'm a little confused as to why my problem went away when I replaced rotors, brake lines, calipers & pads PLUS the master cylinder. I had not seen ANY mention of the booster shaft setting so I had not touched that. I wonder why my brake problem disappeared after that. It has reappeared and the only thing I have not messed with is the brake booster or it's shaft setting.

If I'm understanding your information. It is most likely the shaft setting that's the problem. Not that the M/C port on the factory original M/C or the reman replacement BOTH have port problems.

I didn't want to mess with booster because it seemed to be a lot more trouble to remove it. Really though? You have to remove M/C and booster to get to the shaft and locking nut?

Thank you greatly for the information you've shared!

bamakodaker

 

[BrokFoc]

Well amc49 you did help me here too. Thanks.

My problem is little different but the explanation of the corner bias of the brake systems and the bleeder ports in the MC explained to me why I've been having troubles with those two corners.

What I'm really discovering here however, is the brake system on the older Focus was moronic. But, there have been worse.