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Brake issues- soft pedal ***updated with video***
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- Lifer
- Posts: 11127
- Joined: Tue Feb 10, 2015 10:27 pm
Brake issues- soft pedal
New caliper, i’d suggest that’s where the air is then bigwinn, if you do rubber mallet it the air is usually at the top of the caliper in the ‘corners’ so to speak. Hope you get it shifted.
M roady...OEM CSL’s, strut brace, Remus back boxes, ZHP
MR2 MK 2
E89 35i project car...mapped 365bhp, M4 stoppers & wheels, KWV3’s, H&R front ARB, M3 front arms, strut brace Eisenmann cat back race exhaust, VRSF downpipes inbound
E89 35is
G29
MR2 MK 2
E89 35i project car...mapped 365bhp, M4 stoppers & wheels, KWV3’s, H&R front ARB, M3 front arms, strut brace Eisenmann cat back race exhaust, VRSF downpipes inbound
E89 35is
G29
- enuff_zed
- Lifer
- Posts: 15319
- Joined: Wed Oct 26, 2016 11:05 am
- Location: Attleborough, Norfolk
Brake issues- soft pedal
Just a thought. You could hang the calliper with the pads out and use a wind back tool to push the piston back in. That may help shift the air?
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Onlinebigwinn
- Lifer
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Brake issues- soft pedal
Cheers gents
Will do
Will do
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Onlinebigwinn
- Lifer
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Brake issues- soft pedal
You know how much I love a big hammer
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- Lifer
- Posts: 11127
- Joined: Tue Feb 10, 2015 10:27 pm
Brake issues- soft pedal
Absolutely enuff, just have to watch the fluid doesn’t get pushed out of the filler reservoir, plus you’d need to remove the caliper again as you know, not a huge job obvs. Worth the mallet first imho purely as it’s the easiest way, as I’ve done it myself and had others do it with success, but your suggestion is spot on.
M roady...OEM CSL’s, strut brace, Remus back boxes, ZHP
MR2 MK 2
E89 35i project car...mapped 365bhp, M4 stoppers & wheels, KWV3’s, H&R front ARB, M3 front arms, strut brace Eisenmann cat back race exhaust, VRSF downpipes inbound
E89 35is
G29
MR2 MK 2
E89 35i project car...mapped 365bhp, M4 stoppers & wheels, KWV3’s, H&R front ARB, M3 front arms, strut brace Eisenmann cat back race exhaust, VRSF downpipes inbound
E89 35is
G29
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Onlinebigwinn
- Lifer
- Posts: 4846
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Brake issues- soft pedal
Had some time on this today.
Issue still persists-
Bled (furiously I may add) several times and ABS cleared on inpa
Changed the master cylinder back to the original
Tapped and banged all lines
To be fair there was some residual air in the pipes
However of note- and checked against the coupe and Steve’s m54 z4- there is a hiss sound when pressing the pedal down
I am thinking now that it may be the vacuum servo at fault.
But thanks to all who have helped so far
Issue still persists-
Bled (furiously I may add) several times and ABS cleared on inpa
Changed the master cylinder back to the original
Tapped and banged all lines
To be fair there was some residual air in the pipes
However of note- and checked against the coupe and Steve’s m54 z4- there is a hiss sound when pressing the pedal down
I am thinking now that it may be the vacuum servo at fault.
But thanks to all who have helped so far
If the forum helped you, why not help the forum back. Thats the Z4 way!
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Onlinebigwinn
- Lifer
- Posts: 4846
- Joined: Wed Jul 08, 2020 7:13 pm
- Location: Lincoln UK
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Brake issues- soft pedal ***updated with video***
Still trying to get to 100% with this.
It’s better but not right still.
What’s done:
As above
New fluid
New flexis
New vacuum booster
New master cylinder
I’m still getting softness at the start, which firms up with pedal pumping. If you then leave it 5-10 secs the softness returns
On other cars the pump action makes the pedal hard and it stays hard
The video shows the noises that are heard-
The next step I think is to change the dsc unit… I have one in the shed
Are they all interchangeable (this one is a pre facelift in the spare pile)
Any other ideas?
There are 100% no fluid leaks
Stuart
It’s better but not right still.
What’s done:
As above
New fluid
New flexis
New vacuum booster
New master cylinder
I’m still getting softness at the start, which firms up with pedal pumping. If you then leave it 5-10 secs the softness returns
On other cars the pump action makes the pedal hard and it stays hard
The video shows the noises that are heard-
The next step I think is to change the dsc unit… I have one in the shed
Are they all interchangeable (this one is a pre facelift in the spare pile)
Any other ideas?
There are 100% no fluid leaks
Stuart
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Onlinebigwinn
- Lifer
- Posts: 4846
- Joined: Wed Jul 08, 2020 7:13 pm
- Location: Lincoln UK
- Contact:
Brake issues- soft pedal ***updated with video***
If the forum helped you, why not help the forum back. Thats the Z4 way!
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Online
- Senior Member
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- Joined: Sun Aug 14, 2016 12:30 am
Brake issues- soft pedal ***updated with video***
I have heard that if you remove a caliper, lift it, turn it so that the bleed screw is on the top, block the piston with a caliper retraction tool, it will help get the trapped air out.
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Online
- Senior Member
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- Joined: Sun Aug 14, 2016 12:30 am
Brake issues- soft pedal ***updated with video***
Saw this on another forum.
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- Screenshot 2024-06-01 at 19-40-53 Facebook.png (240.24 KiB) Viewed 178 times
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Onlinebigwinn
- Lifer
- Posts: 4846
- Joined: Wed Jul 08, 2020 7:13 pm
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Brake issues- soft pedal ***updated with video***
Just saw that
I’m going to give it a go
I’m going to give it a go
If the forum helped you, why not help the forum back. Thats the Z4 way!
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- Rockhopper
- Senior Member
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Brake issues- soft pedal ***updated with video***
Do you get the hiss sound with the engine running? With the engine off you may well get it as the residual vacuum in the servo is released - the pedal will also go harder at the same time.