I have recently replaced (yesterday) my rotor, pads (semi-metallic) and calipers on the front brakes. I did, with a friend's help, bleeding of the brakes on the front until all air appeared gone. I replaced all the fluid that was lost in replacing the calipers, however I now had have the soft mushy brake pedal and there appears to be no reason for that.

I assume that the front and back brakes are separate systems and in my changing the front calipers, there is no chance that I got air into the back brakes??? (from the fluid loss). There are no leaks in the system either.
I did not have mushy brakes before and changed everything as it is easier to do one time than 3 times. The brakes will still stop fine, but have to get closer to the floor than I like or would think is normal.

It is possible in bleeding the brakes I could have contaminated the brake pads with brake fluid- not the first time someone would have done that. Any thought that could be the issue??

Rear brakes seem fine and EPB is more than fine. Fluid filled to max (super dot 4 or 4 + if that makes any difference).

Any suggestions, ideas or direction would be he highly appreciated.

(by the way, I changed the calipers as the front left one seemed to be lazy and not taking the pad off the rotor cleanly and I was getting a sound of it releasing and during application that sound like a small knock, clunk or something of that nature. If I stopped hard- it would not do that, but I do not jack rabbit a car and then try to stand on the brakes and much of what I do is city traffic and if anything use the brakes more softly (try to minimize any feeling of recoil in stopping the car))

Thanks as always

Tom in Dallas/Plano

05 S-Type 3.0 83k

 

They're usually (& probably with yours) diagonal separate (almost) circuits.

I can only think you still have air in there.

See who else has ideas...

 

Sounds like air, is the bleeder right at the top? You could have a pocket of air in the new caliper.

 

Yes, the bleeder is at the top. We did open and close and up and down on the brake pedal about 10 times a side and all the air bubbles disappeared and we got a steady stream of fluid. Further we jst opened the bleeder and got a steady stream as well.
Do you think we should just go back and do it a few more times.

Thanks

Tom in Dallas/Plano

 

They certainly appear to be separate circuits- so you are thinking air as well. Any other "fail safe" way to do the bleeding short of going and getting a shop to do it on a machine?

Curious as to what brake fluid you use- not to get a brand argument started?

Thanks

Tom

 

I think it's meant to be ITT Super DOT4.

 

Brand will make no difference for the problem at hand.

Try bleeding the rears also.

 

Thanks, I got a vacuum pump and such from Harbor (Pittsburgh Tool ) and will see what gives.

Will let you know the results.

Tom in Dallas

 

Well that was the problem. I will do the rears as well. Should I redo the front after the rears or since separate circuits/lines it is not like cars of 25 years ago??

Thanks

Tom in Dallas

 

Bleed longest line to shortest two or three times. Remember this fluid has to go through the ABS system too. After that, it takes new pads and rotors a few miles to seat and work like new. I just did all four wheels and it was soft for about 10 miles. I did not open the lines. Just rotors and pads and clean and grease.

 

Jazz...you've got four brakes but one brake pedal, one ABS pump/module and one reservoir, no? Take David's sound advice and bleed the entire system as he suggests, longest path to shortest in descending order.

 

I think you are right. I will do so as soon as rain goes away.

Tomi in Dallas

 

You are not bleeding the ABS. Unless you have the factory tool there is brake fluid that is trapped inside the ABS system.

On another forum one of the suggestions was to bleed your brakes and then find a dirt road. Use the brakes so the ABS kicks in and cycles the pump and you feel the feedback in the pedal. This forces brake fluid from the normal brake system into the ABS. The old ABS fluid has now been pushed into the existing brake fluid and the clean brake fluid you just added to the master cylinder is now inside the ABS.

Not sure that works and for that car I purchased a factory ABS tool which cycled the pump independently of the car.

Still not sure how important getting the fluid changed in the ABS is but I guess any extra bit is a plus.
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Thanks. I had no intention of trying to do anything with the ABS system. We have had rain and it works fine. I still have this mushy BS and noise with the front pads like the caliper are not exerting enough pressure (I know air in the line).

If I stop slowly then the sound is the exact same as if you just went to a power wash and washed your car and then drove out with wet rotors and stepped on the brakes and got that groan/moan or whatever you might describe it until they got dried off by braking.

This is very frustrating to have to deal with.

I am going to start at back passenger and use my vacuum tool and see that I can get the air out of this thing.

Tom in Dallas

 

Its a good idea to also flush out and replace the fluid.

Not sure how often this has been done on your car if ever
Brake fluid collects moisture that creates a spongy pedal

As the brakes warm the water in the fluid boils and turns to gas creating air gaps and a spongy pedal

Just keep filling the reservoir and keep bleeding the longest line till you see a colour change from the new fluid. This will take a bit as you draw the new fluid through. Then move onto the next longest line and so on. The last 3 will be quick as you have already drawn most of the new fluid through the system

I did one 2 weeks ago and the old fluid came out black!!!!

Cheers
34by151

 

Just my experience but I have had very poor results with a vacuum bleeder from Motive Power. Always had a soft pedal.

I am sure it's my technique but the plane old pushing on the brake pedal does the best job for me.

Motive Products #1 Selling DIY Brake Bleeder
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I prefer this style one

Vizibleed Brake & Clutch Bleeder - One Man - Supercheap Auto Australia

Cheers
34by151

 

Is there ANY chance you put a pad in backwards? A moan can also be metal to metal. Take your flash light and really check that. If one is wrong, you should be able to see it.

 

This was the one I used and it is a simple one man job and worked easily and well.

Brake Bleeder and Vacuum Pump Kit


Tom in Dallas

 

Thanks

Bled all four, even though the backs worked fine and the color on the backs was just a dark red/gold.

Did the fronts and clearly the new fluid has taken over.

Problem was that when I changed the calipers and did the 2 man push the pedal approach, I apparently contaminated the pads. Got new ones for front and all is now good along with quality brake fluid (Pentosin Super Dot 4). I have bedded the new pads on the front and they can cool down over night and everything seems ready and green to go.

Now I am battling this silly thing squeaking on my passenger side, but only at the first couple of millimeters of travel up and down or start/stop..

Anyone replace this and how hard was it?

BUSH-WISHBONE - Terrys Jaguar Parts - C2C4438

Thanks

Tom in Dallas