Hard Brake Pedal
12-09-2014, 01:58 PM
#12
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My Ride: 2006 530xi touring
Model Year: 2006
Engine: 3 liter
Second-hand brake boosters are pretty common and cheap.
They don't fail very often and every E60/E61 that is broken has one. I think they're the same for all engine sizes too.
Fitting isn't that bad - the main headache is that you have to completely bleed the entire braking system because you need to disconnect the brake lines to the master cylinder.
They don't fail very often and every E60/E61 that is broken has one. I think they're the same for all engine sizes too.
Fitting isn't that bad - the main headache is that you have to completely bleed the entire braking system because you need to disconnect the brake lines to the master cylinder.
Brand new rebuilt unit is $140. Why buy used?
12-14-2014, 03:39 PM
#13
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My Ride: 2006 530xi touring
Model Year: 2006
Engine: 3 liter
Closing this out.
The rebuilt booster came today, installed it and all is well. One hint for the next guy, at least on E60, install the master cylinder first on to the booster, then install the assembly into the car. You save a bundle of time.
The rebuilt booster came today, installed it and all is well. One hint for the next guy, at least on E60, install the master cylinder first on to the booster, then install the assembly into the car. You save a bundle of time.
12-17-2014, 09:49 AM
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My Ride: 2006 530xi touring
Model Year: 2006
Engine: 3 liter
Well, all is not well.
I drove it for 1 mile and ALL BRAKES locked up. Released the lines, rebled the brakes, make sure fill up fluild to Max level and no more. Drove it and immediately the brakes are dragging. Pull into the garage and they all locked up.
Is it possible that the master cylinder decided to go just now? Or, it is possible that the new rebuilt booster is somehow causing the brakes to bind and lock up?
I drove it for 1 mile and ALL BRAKES locked up. Released the lines, rebled the brakes, make sure fill up fluild to Max level and no more. Drove it and immediately the brakes are dragging. Pull into the garage and they all locked up.
Is it possible that the master cylinder decided to go just now? Or, it is possible that the new rebuilt booster is somehow causing the brakes to bind and lock up?
12-17-2014, 04:55 PM
#16
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My Ride: 550i
Model Year: 2010
Did you touch the "push-rod" of the brake pedal that pushes on the MC? Because of production variations, and especially with aftermarket parts, the booster might not be the exact same size so the pushrod will need to be adjusted so there's 1-3 mm of brake pedal play. By the sounds of it, it's probably pushing the MC slightly causing the brakes to be applied. The pushrod will probably have to be shortened.
This is the procedure for a Honda, but I think for a BMW it should be similar. I replaced the MC on my acura 2 years ago and luckily I didn't have to adjust the pushrod.
http://my.cardone.com/techdocs/PT%2053-0001.pdf
This is the procedure for a Honda, but I think for a BMW it should be similar. I replaced the MC on my acura 2 years ago and luckily I didn't have to adjust the pushrod.
http://my.cardone.com/techdocs/PT%2053-0001.pdf
Last edited by cakes; 12-17-2014 at 05:02 PM.
12-17-2014, 07:35 PM
#17
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My Ride: 2006 530xi touring
Model Year: 2006
Engine: 3 liter
Did you touch the "push-rod" of the brake pedal that pushes on the MC? Because of production variations, and especially with aftermarket parts, the booster might not be the exact same size so the pushrod will need to be adjusted so there's 1-3 mm of brake pedal play. By the sounds of it, it's probably pushing the MC slightly causing the brakes to be applied. The pushrod will probably have to be shortened.
This is the procedure for a Honda, but I think for a BMW it should be similar. I replaced the MC on my acura 2 years ago and luckily I didn't have to adjust the pushrod.
http://my.cardone.com/techdocs/PT%2053-0001.pdf
This is the procedure for a Honda, but I think for a BMW it should be similar. I replaced the MC on my acura 2 years ago and luckily I didn't have to adjust the pushrod.
http://my.cardone.com/techdocs/PT%2053-0001.pdf
12-17-2014, 07:50 PM
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My Ride: 2006 BMW 550i
could you try maybe loosening the master cylinder bolts so that the cylinder moves away from booster a bit. and see if that fixes issue?
is the pedal returning all the way up?
is the pedal returning all the way up?
12-19-2014, 08:33 PM
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dont drive with the master cylinder loose, but just loosen it to see if it gets rid of the stuck brakes. the booster pushes on the master cylinder rod. that may help you determine if the rod is getting stuck.
but first i'd check to make sure pedal comes all the way up first.
but first i'd check to make sure pedal comes all the way up first.