[emax13]

Do you need to do anything special to bleed brakes?

Any requirments for ABS or proportioning valves or just bleed like normal? Anyone verify this in the Bently manual?

[zemperaye]

http://m3.madrussian.net/diy_brake_bleed.shtml

there really isnt anything special. Just remember to bleed the clutch as well. Are you flushing/replacing system? or just bleeding? ^^ should help.

[hogger453]

According to my Bentley, if no air was/is introduced just behind the master cylinder than it's a pretty much a straight forward pressure bleeder procedure. But something interesting: Pressure bleeding at no more than 2 bar but should not be more than 20lbs. while someone is pumping the brake, interesting. Brake pedal should be held down before the bleeder is closed.

If air was introduces just after the master cylinder than you would need a
DISplus/GT1 factory scan tool.

The ASC and DSC systems use electronis controls and a sophisticated hydraulic unit. Once air enters the hydraulic unit, it is difficult to remove using traditional methods.

[anti-roll]

Originally Posted by zemperaye

http://m3.madrussian.net/diy_brake_bleed.shtml

there really isnt anything special. Just remember to bleed the clutch as well. Are you flushing/replacing system? or just bleeding? ^^ should help.

Unless you somehow got air in the clutch line, bleeding it is not necessary.

Also, Madrussian's bleeding procedure via a pressure bleeder is a waste of time IMO. Bleeding the system the conventional way (with a helper pumping the pedal) is faster and less of a hassle.

[RedM3/4]

Several have no problem, but it isn't exactly uncommon to damage the master cylinder on newer cars; the piston being pushed past where it normally would travel is described as being the potential cause. So maybe don't push as hard and far as you can go, or put another thickness of carpet or something behind the pedal for some insurance if you're not going to use a pressure or vacuum bleeder.

ADS

Originally Posted by swaybar3

Unless you somehow got air in the clutch line, bleeding it is not necessary.

Also, Madrussian's bleeding procedure via a pressure bleeder is a waste of time IMO. Bleeding the system the conventional way (with a helper pumping the pedal) is faster and less of a hassle.

[anti-roll]

^^^ I bleed my brakes twice a year. That's 8 times in the last 4 years. And I never ran across anyone with M3 who damaged the master cylinder from bleeding the brakes using the old method, which IMO is still superior to the $40 pressure bleeder.

Originally Posted by DZeckhausen

This is more of an issue with older cars that use cast iron master cylinders and not as much of an issue with the aluminum ones. It also is an issue only when the brake fluid has been neglected and absorbed enough moisture to allow this corrosion process to start. But you're absolutely correct. If you bleed the brakes on an older GM car (like my 1996 Impala SS) and it's the first time the fluid has been changed in 4 or more years, then you will probably tear up the seals and, shortly after the bleed job, you will find the brake pedal slowly sinking to the floor.

For such older cars with cast iron master cylinders and neglected fluid change intervals (or a used car with an uncertain past), there is a way to perform a traditional bleed without the risk of damaging the seals in the master cylinder. Simply place a block of wood under the brake pedal to prevent it from going all the way to the floor. This prevents the master cylinder seals from traveling into those nether regions where the rust has accumulated. So you can still get the benefit of a "performance" brake bleed.

Pressure bleeders that use compressed air to pressurize the fluid in the reservoir have a couple of disadvantages over traditional 2-person bleeding. First, you cannot apply a pressure in excess of 25 - 30 psi without either rupturing the plastic tank or blowing it off the top of the master cylinder. Either scenario results in a very ugly mess! Much higher pressures are possible using a foot on the brake pedal and trapped air bubbles are more easily driven out of the system with several hundred psi, rather than the lazy trickle of fluid that results from the use of a pressure bleeder.

Second, the use of an inexpensive pressure bleeder that applies pressurized air directly to the fluid (hand pump or compressor driven) results in gas bubbles becoming entrapped in the fluid, with a correspondingly softer pedal being the result. (Analogous to how excess nitrogen is dissolved into your bloodstream during deep sea diving.) High-end professional pressure bleeders use a membrane to apply pressure to the fluid and isolate it from the compressed air. This prevents the entrapped gas problem, but it does not get around the 25 - 30 psi limitation of this type of bleeder.

[hogger453]

Originally Posted by swaybar3

^^^ I bleed my brakes twice a year. That's 8 times in the last 4 years. And I never ran across anyone with M3 who damaged the master cylinder from bleeding the brakes using the old method, which IMO is still superior to the $40 pressure bleeder.

Same here. The two person method is still the best way to bleed.

I bleed my brakes about three to four times a year, depending on track duties.

If there is another body present, he will be designated to pumping (the brakes).

If I'm by myself than the pressure bleeder comes out.

[emax13]

My 2 year flush is due this summer. The car has not (yet) seen the track and fluid in the MC looks good.

My plan was to install speed bleeders and flush manually.

I was also debating installing SS lines, if I can do without draining to much fluid.

[TaeIm]

Originally Posted by zemperaye

http://m3.madrussian.net/diy_brake_bleed.shtml

there really isnt anything special. Just remember to bleed the clutch as well. Are you flushing/replacing system? or just bleeding? ^^ should help.

Is it really REQUIRED to bleed the clutch at the same time ?

[spumoniM3]

Originally Posted by TaeIm

Is it really REQUIRED to bleed the clutch at the same time ?

Yes, it's the same system. When I put my SS brake lines on, I thought the same thing. I didn't get air into the clutch, why should I bleed it? If you don't your brake pedal feels like there is air somewhere in the system. I didn't get a good brake pedal until I bled the clutch.