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Discussion Starter · #1 · (Edited)
Sorry for the long post ahead but I thought more details would help...


I’ve changed my rotors and pads two weeks ago but the brakes don’t feel great at all since.
To be more specific I have to press harder/further on the brake pedal to get them to brake well.
Today I just bled my brake lines and all went well. Quite a bit of air bubbles came out in the rear. Not

much at all in the front. The brake fluid was quite old it seems.
But after that the brakes still don’t feel that great. A little better but not great.

In some occasion (not always) when I first step in the car and put my foot on the brake pedal I here a small metal clunk at the pedal and then after that it feels more solid, as if the pedal does not have much build up pressure at first.
If I press hard the car will stop and I can feel/hear the pads bitting on the rotors. But it still further down the pedal travel.

Another thing is that when the car is at iddle, I have not drove yet, I can pump the brake pedal and it gets strong. But if I stop pumping the brake pedal it will slowly depress. Not the all way. But enough to make me think that’s strange. I don’t recall this being normal. Maybe it is.I don’t know… I also just noticed that when I pump the brake pedal, still at iddle, the vacuum pump spins (at it always does when I first start the car and use the brakes) but I can also hear air leaking from it. If I stop, the pump eventually stops as well and so does the leaking air noise.

So my question is what can be wrong with my brakes?

Q1: Is it possible I picked-up a bad pad and rotor combination (I only have 300mm rotors to the front)?
I installed ECB slotted rotors, Hawks HPS in the front and Akebono ceramic in the rear.

Q2: Is it possible something got loosened up with the pedal position itself?

Q3: Is it possible the vacuum pump is the problem, but I always thougth that it was affecting the brakes only when the car is stationary and needs a vacuum boost.

I’m a bit puzzled.

I have an appointment in a little over a week from today for other repairs but I’d like to know what it could be before I mentioned it to my mechanics and have them fix it for good!
Thanks to anyone who could shed some light on this…
 

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1. It should have never had any Air in the Lines . Have You had to do a few Panic stops ?

2. Are You sure Vacuum line is ( On ) the Intake Tube in back of It .

I'm wondering how the Air got in there in the First Place ?


Clunk at Initial Pedal - could You record this : ?
 

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Discussion Starter · #3 ·
1. It should have never had any Air in the Lines . Have You had to do a few Panic stops ?

2. Are You sure Vacuum line is ( On ) the Intake Tube in back of It .

I'm wondering how the Air got in there in the First Place ?
Isn't it why bleeding the brake is done in the first place?
Humidity in the line can also transform in air bubbles if it boils I suppose.
Or air could have sipped in when I pushed back the piston.

I did do some pad sitting procedure which involves a series of hard braking...


Oh and yes all vacuum lines are on.


Clunk at Initial Pedal - could You record this : ?
It's going to be hard to record since it does not do it every time. I'll give it a try...
 

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So, I am no stranger to brake problems. I'll try to lend a hand...

It's perfectly normal for a car to develop air in hydraulic lines. Brake fluid is hygroscopic, meaning it will absorb water. Under heat and pressure during braking, the water that collects in the reservoir over time will boil, and you have an air pocket. It just happens. So yes, brake bleeding is a necessary service.

I'm not sure how to break in hawk or ceramic pads, but for other performance pads I have installed, they called for something like three stops from 35mph in 30ft in order to "seat in the pads" or something. Well, I didn't do that. Didn't know I had to. I went to two different shops and they said my brakes were fine. I still thought they weren't stopping the car... So check for a break-in procedure.

Also, I'm not sure I understood you correctly from the brake bleeding thread, but I believe you siphoned out old fluid from the reservoir? If you tried to suck out every last drop, then you may have introduced a bubble into the master cylinder. Some cars require you to "bench bleed" the master before installation in the car.

Just checking, but did you clean all parts with brake cleaner before installation? You're not trying to stop on the greasy film on new rotors, are you?? Also, did you clean and re-grease the bolts the calipers slide on? The clunk and erratic pedal may be from the calipers sticking on those slides sometimes, sliding well other times.

You know what may not hurt to try (if you have all the time in the world on your hands...) Try re-installing the old brake parts if they are in acceptable condition. That way you can isolate the problem from being the "new parts" or from the brake bleeding operation.

Ask me how I know of all these faults... Done 'em myself.
 

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Sorry, missed when u said u did seat the pads... Oops...
 

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Discussion Starter · #6 · (Edited)
So, I am no stranger to brake problems. I'll try to lend a hand...

Also, I'm not sure I understood you correctly from the brake bleeding thread, but I believe you siphoned out old fluid from the reservoir? If you tried to suck out every last drop, then you may have introduced a bubble into the master cylinder. Some cars require you to "bench bleed" the master before installation in the car.

Just checking, but did you clean all parts with brake cleaner before installation? You're not trying to stop on the greasy film on new rotors, are you?? Also, did you clean and re-grease the bolts the calipers slide on? The clunk and erratic pedal may be from the calipers sticking on those slides sometimes, sliding well other times.

You know what may not hurt to try (if you have all the time in the world on your hands...) Try re-installing the old brake parts if they are in acceptable condition. That way you can isolate the problem from being the "new parts" or from the brake bleeding operation.

For the siphoned fluid I thought of that and did not over remove the fluid. I was concerned to bring air in the fluid as well so I mostly remove the gross of the old fluid leaving a layer at the bottom flat surface of the tank. There where plenty of fluid further down.

Yes, I cleaned all the parts when I replaced pads and rotors. It took me a while actually, dusting off with a wire brush the old brake dust from inside the caliper parts. And, yes I was careful not to damage anything in the process. I did not over do it or I would have spend the whole day :p
I even re-did my rears because I had forgotten to put lubricant on the back side of the pads. So I lubricated and clean all the slider bolts as well. I'm pretty sure at this point the pads and rotors are installed well and confident (not certain) they are seated well too.

What do you mean by:"You're not trying to stop on the greasy film on new rotors, are you?? " There is no grease on my rotors or pads...

No that noise I'm talking about seems to come from the pedal itself or close to it. I could not replicate it this evening.

I though of putting back the old brakes but they are in pretty bad conditions. They probably won't sit well now that I removed them. The rear pads where almost gone (a few mm left).
One of my biggest concerned is that I show up at my dealership and they tell me the problem is from these none oem rotors and pads... Then what do I say, check again?

I tell you, I don't know what it could be other than a problem with the vacuum pump or with the caliper pistons but on all of them I'd be surprised.
 

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Well, I'd say it is the combination of the brake discs and pads.

EBC has recommendations (for example, EBC Greenstuff and the slotted discs etc.).

The problem is a lot of the time, that a mix and match in pads and discs to your wishes is a little awkward, as a lot of discs are specced for certain pads. You probably wouldn't use ceramic pads on standard discs as there are no advantages.

Check if your discs up front haven't glazed.
 

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Discussion Starter · #8 ·
Well, I'd say it is the combination of the brake discs and pads.

EBC has recommendations (for example, EBC Greenstuff and the slotted discs etc.).

The problem is a lot of the time, that a mix and match in pads and discs to your wishes is a little awkward, as a lot of discs are specced for certain pads. You probably wouldn't use ceramic pads on standard discs as there are no advantages.

Check if your discs up front haven't glazed.

So much for people saying that rotors are just a piece of metal from what you're saying . . . Though I hear you about matching part brands, but dam if that's the case I don't see the point in buying performance parts. I can understand that if you're optimizing performance but if it gives you worse result than plain OEM rotors I don't see the point...

I'm still not sure that's what it is. Hmmm we'll see on that one. Nothing I can do there until someone else look at the car.

The rotors looks great actually. No glazing or anything. The EBC coating wasn't coming off entirely on the rear. I'm guessing because of the air in the rear brake lines. I got to work this morning and it seems the rear rotors are getting more clean off that coating in the micro grooves of the rotors. This was especially true on the outer portion of the rotors. So I have a little thread of hope...
 

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This sounds entirely like a bleeding issue (due to the pedal travel), Do the 40s have the retainer springs that could have been installed improperly? I highly doubt it is the rotor/pad combination. nI would re-bleed, then again and see what you get.
 

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Discussion Starter · #11 · (Edited)
For the most part I followed Melvin's write up:
http://forums.swedespeed.com/showthread.php?172638-Write-up-Bleeding-brake-system/page2

How did I bleed?

I used Volvo DOT 4+ fluid
Did one side at a time in that order right rear, left rear, right front left front.
Emptied some of the fluid in the master cylinder tank. Did not dried it out. Just enough to add enough new fluid. About 6/7 oz
Install catch bottle + tubing on bleeder.
Pressurized master cylinder with power bleeder to 5/6psi.
Opened bleeder valve.
Let drained until master cylinder tank was low enough to do next bleeder. I would position catch bottle tube ending above bleeder so all air bubbles would come out rather than risk some of them going back in.
Close the bleeder valve before depressurizing. I double check each valve every time to make sure they where closed properly.
Open master cylinder tank to refill before continuing to next bleeder valve. I never let the fluid level below minimum.
and so on.

Caught about 24oz of old fluid in the catch bottle. Old fluid was pretty dark.


Overall it seemed safe and easy.
I guess there could still be some air in the lines. but how to be sure it's all out?
I'm reluctant to spend more if my mechanic is going to do it yet again!
 

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Sounds like a thorough, quality bleed job. To know all the old fluid is out, watch for the color to change in your catch can! When you start pushing clean fluid thru the bleeder valve, you have fresh fluid from the master cyl all the way to that wheel.
 

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What do you mean by:"You're not trying to stop on the greasy film on new rotors, are you?? " There is no grease on my rotors or pads...
There's always a thin film of grease on the new rotors to inhibit rust during shipping and sitting on store shelves. You have to use brake cleaner to get that off before you use the brakes. It sounds like you did that, but I wasn't sure at the time.

Also, something that is possible during a brake job is to tear/damage the rubber brake lines by hanging the calipers by the line during pad replacement (or just moving aroung an old line). A torn line will cause a long brake stroke and bad braking. The master cylinder has two hydraulic systems (usu. one for LF/RR, and the other for RF/LR) so that in the event of a brake line breaking , you will still have *some* braking power. The system with the damaged line will have no braking power, but the good system will still be able to perform.
Have you checked the level of brake fluid in your reservoir recently? Have you checked for brake fluid leaks? (I'm sure you have... but we're here trying to brainstorm ideas for you, right??)
 

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Discussion Starter · #14 · (Edited)
Thanks Bootsie for helping figuring this out.

Hmmm I'm surprised they would ship rotors with a thin layer of oil even if it was to prevent rust. I would think that would be a liability issue!
Mine came with a zinc coating on it so I doubt they would have added oil as well. No point to that.

Yes I've check the brake fluid and the level seems to stay the same so I would think there is no leak.

I hang the caliper by an adjustable cord to the suspension so there should never have been too much stress on the brake line. That said I did move the caliper around to clean. Wouldn't a torn line result in a leak?
Last I checked things looked alright.

Can someone confirm if a faulty vacuum pump reduces braking power. I'm suspicious of my vacuum pump but if it does nothing to the brake during driving, and only at idle, than it probably isn't that.
 

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Discussion Starter · #15 · (Edited)
Vacuum pump...

So I took two videos 1 showing the vacuum pump air noise and 2 showing my foot on the pedal and how It never gets to a full stiff brake and further more how it deflates once I stop pumping.
Both video are somewhat in sync so when I stop pumping and the brake pad fades is when the pump noise dies out to a silent.

And by the way the pump use to run for some time when I inserted the key but it does not anymore. Now it does that when I press the brake pedal...

Also can someone tells me for sure that they don't have that air leak noise so I don't mistake a normal noise for a damage pump. Thanks!

I seem hesitant on this one but I was hold my phone at the same time :p
 

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idk but to me that pump doesnt sound healthy, and since theres no obviously break line leaks, and you did a dam good thorough job bleeding your breaks, id say replace that pump.
 

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Discussion Starter · #17 · (Edited)
I wonder if there is a newer model part number for that pump I could use from newer C30S/V50s/S40s... If I get an old one it might do so same eventually... If I recall, these pump aren't cheap!

edit:
Man, it's like $200

edit#2:
I forgot to mentioned this because it's kind of obvious but those videos are done with the engine turned off (when the pump is most needed I guess)

edit#3:
I did turn the engine on at idle and the pump still kicks in with same noise.
 

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Discussion Starter · #18 ·
Anyone else has some thoughts on this?
look at the videos down below...
THX!
 

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How are you bleeding? Almost sounds like there's an issue with the lines holding pressure. Also what fluid?
Mt Thoughts also , but I was mentioning the Air ( Above ) - as He had just bleed - so It was probably a Miss Bleed - It Happens .

His Procedures look OK , I still prefer Gravity for or a Dam Good Helper and a Slow Pump - stopping them about half way down - I just Shut the Bleeder . ( Do It again ) .

My Pump shuts down after a short period , so Pump sounds UN-Healthy . ( Good Vid ) - that Helps .

I Know VW said - some of their Tech have - Blown out Clutch Slaves on the MT with the Pressure Bleeder systems . or even the Master Cly.

Replacement of a Volvo vacuum pump Replaced - about 6-9 months ago on SS - with similar sound , but I don't remember anything about Air in the Lines .

1. Bad Pump or Master Cly - seems it can't hold pressure , as far as Driving goes after 1/2 mile the Engine should be making enough to Hold Pressure .

Part # just for referral : http://www.autopartsnetwork.com/sho...uum_Pump-make_Volvo-model_C30-year_2008.html?

Air in Line - throws - Me Off - could little Brother or GF shake the Brake Fluid can - thinking it needed to be - Mix up well ?
Or as other SS Member Mentioned above - Low Master Cly - which could take several attempts to get it all out . ( As Far as Air in Line )

2. The way the Pedal is going down it looks like an Internal Leak , If You don't see an External Leak .
 

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Other Information floating around on Master Cly . :

I wondering If some of the Brake Issues aren't Caused by Weak Master cly's . : Not Pulling Brake Fluid Back or is this more a Symptom Brake Lines Swelling ?

Item Affected: SERVICE BRAKES, HYDRAULIC:FOUNDATION COMPONENTS:MASTER CYLINDER
Date Announced: 3/5/2008

Description of Recall:
VOLVO IS RECALLING 1,114 MY 2007 C30, C70, S40, AND V50 PASSENGER VEHICLES. A SOFT ANODIZED LAYER IN THE MASTER CYLINDER MAY TRIGGER EARLY WEAR ON A RUBBER SEAL THAT CAN RESULT IN INTERNAL LEAKAGE OF BRAKE FLUID. IF AFFECTED, THE DRIVER MAY EXPERIENCE REDUCED BRAKE PERFORMANCE WHEN APPLYING AND MAINTAINING FORCE OF THE BRAKE PEDAL.
Action Needed To Fix It:
DEALERS WILL INSPECT THE MASTER CYLINDER. THE BRAKE MASTER CYLINDER AND BRAKE FLUID RESERVOIR WILL BE REPLACED AND CERTAIN BRAKE LINES CLEANED FREE OF CHARGE. THE RECALL BEGAN ON MARCH 11, 2008.
 
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