BMW M3 Forum (E90 E92)

BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read


Go Back   M3Post - BMW M3 Forum > E90/E92 M3 Technical Topics > Suspension | Brakes | Chassis
 
BPM Sport
Post Reply
 
Thread Tools Search this Thread
      11-01-2013, 09:10 AM   #1
happos2
Dingleberries
 
Drives: Gray E92 M3
Join Date: May 2012
Location: Indiana

Posts: 1,028
iTrader: (2)

Brake Fluid Qnty

Easy question hopefully, how much new brake fluid do you need to do a full flush? RBF600 looks to come in 500ml so I and trying to decide how many bottles I need.

Thanks!
happos2 is online now  
0
Reply With Quote
      11-01-2013, 09:45 AM   #2
1MOREMOD
2014 Track Days - 6|Ridge 1:54:61|Pacific 1:35:72
 
1MOREMOD's Avatar
 
Drives: Race car->
Join Date: Mar 2009
Location: check your mirrors

Posts: 11,607
iTrader: (5)

dealer will say 2 liters. depends also if you are purging the 6mt. i have found for regular flush it is between 1-2 liters, closer to 1 so 3 bottles of 500mls should do.
__________________

02 Tiag e46 M3|6MT|GC plates|MCS c.o.|GC bars|GC race control arms|GC bushings & bearings|BW eng. & tran. mounts|subframe kit|BW race shifter|BW Jaffster|Euro header|BW race|K&N c.a.i.|Epic race tune|Rouge pulleys|Seibon CF hood|CSL bumper|ST-40|XR-2|SS lines|half cage|Recaro profi|Profi 2 harness|BMWpedals|BW studs|
1MOREMOD is online now   United_States
0
Reply With Quote
      11-01-2013, 11:28 AM   #3
happos2
Dingleberries
 
Drives: Gray E92 M3
Join Date: May 2012
Location: Indiana

Posts: 1,028
iTrader: (2)

Quote:
Originally Posted by 1MOREMOD View Post
dealer will say 2 liters. depends also if you are purging the 6mt. i have found for regular flush it is between 1-2 liters, closer to 1 so 3 bottles of 500mls should do.
Well I have a 6MT... So stupid question. Does flushing the brakes also purge the master cylinder for the 6MT? I know they share the same box or something like that, but are internally seperate...
happos2 is online now  
0
Reply With Quote
      11-01-2013, 11:29 AM   #4
happos2
Dingleberries
 
Drives: Gray E92 M3
Join Date: May 2012
Location: Indiana

Posts: 1,028
iTrader: (2)

Quote:
Originally Posted by 1MOREMOD View Post
dealer will say 2 liters. depends also if you are purging the 6mt. i have found for regular flush it is between 1-2 liters, closer to 1 so 3 bottles of 500mls should do.
Well I have a 6MT... So stupid question. Does flushing the brakes also purge the master cylinder for the 6MT? I know they share the same box or something like that, but are internally seperate...

I will be doing the manual tranny fluid and diff fluid from underneath the car later this winter.

I really appreciate the help.
happos2 is online now  
0
Reply With Quote
      11-01-2013, 11:44 AM   #5
BimmerRob08
Major
 
BimmerRob08's Avatar
 
Drives: 2008 M3, Space Gray
Join Date: Mar 2008
Location: KIKR (ABQ), NM

Posts: 1,255
iTrader: (0)

I've been told 3 liters for a complete flush. I've done it several times when installing my BBK and doing other brake jobs on my M3. I've got a 6MT too. So if your going to use a Brake pressure bleeder, like I do. You'll want to make sure you have a full 3 liters...if not more.

Reason being is you want to make sure you don't ever, ever run it dry while bleeding your last caliper as the level gets low. You'll suck in air and screw it all up and introduce air into the ABS system. So don't go cheep, just get 3 full liters, maybe 4 to be safe, and make sure you watch it closely as you get to the last caliper (normaly the front-left). When i get to the last caliper, I make sure the pressure bleeder still has enough fluid in it. Maybe about 1.5" measured from the bottom with fluid, not sure how much that is, maybe 1/2 liter. You can save the rest or pour the good stuff back into the bottles from the pressure bleeder when done.

As for the clutch. Its to the left of the transmission. There is a bleed port. It's made of plastic if I remember right so don't over torque it! No need to.

Bleed out about 1/3 to 1/4 worth of a brake bleed catch bottle. I think that is plenty. And you don't have to do that everytime you bleed the brakes but no harm if you do.

Good luck.
BimmerRob08 is offline   United_States
0
Reply With Quote
      11-01-2013, 11:46 AM   #6
1MOREMOD
2014 Track Days - 6|Ridge 1:54:61|Pacific 1:35:72
 
1MOREMOD's Avatar
 
Drives: Race car->
Join Date: Mar 2009
Location: check your mirrors

Posts: 11,607
iTrader: (5)

I never purged the 6mt when I did the brake flush on my e90. I'm unsure what the procedure is but just a regular flush won't empty it. Probably why I needed less volume than the dealer quotes. Maybe bmw135er will chime in he is my personal bmw tech.
1MOREMOD is online now   United_States
0
Reply With Quote
      11-01-2013, 02:51 PM   #7
happos2
Dingleberries
 
Drives: Gray E92 M3
Join Date: May 2012
Location: Indiana

Posts: 1,028
iTrader: (2)

Thanks for the information all. Very helpful.
happos2 is online now  
0
Reply With Quote
      11-01-2013, 03:07 PM   #8
apecush
Lieutenant
 
Drives: 2008 E90 M3
Join Date: Aug 2011
Location: Edmonton

Posts: 430
iTrader: (2)

3L?? Wow.

I alternate between blue and amber fluid for my flushes. With sucking all fluid out of the reservoir (to minimize fluid mixing), a brake flush (i consider the lines flushed when the color changes) uses around 800ml.
apecush is offline  
0
Reply With Quote
      11-01-2013, 03:10 PM   #9
apecush
Lieutenant
 
Drives: 2008 E90 M3
Join Date: Aug 2011
Location: Edmonton

Posts: 430
iTrader: (2)

Quote:
Originally Posted by BimmerRob08 View Post
You can save the rest or pour the good stuff back into the bottles from the pressure bleeder when done.
No. Once the fluid is opened, if it isn't in the brake system within a couple days, discard it.
apecush is offline  
0
Reply With Quote
      11-01-2013, 04:53 PM   #10
1MOREMOD
2014 Track Days - 6|Ridge 1:54:61|Pacific 1:35:72
 
1MOREMOD's Avatar
 
Drives: Race car->
Join Date: Mar 2009
Location: check your mirrors

Posts: 11,607
iTrader: (5)

Quote:
Originally Posted by apecush View Post
3L?? Wow.

I alternate between blue and amber fluid for my flushes. With sucking all fluid out of the reservoir (to minimize fluid mixing), a brake flush (i consider the lines flushed when the color changes) uses around 800ml.
yeah 3 liters is way too much unless you are running an extra half liter thru each caliper just to make sure you got it all out.
__________________

02 Tiag e46 M3|6MT|GC plates|MCS c.o.|GC bars|GC race control arms|GC bushings & bearings|BW eng. & tran. mounts|subframe kit|BW race shifter|BW Jaffster|Euro header|BW race|K&N c.a.i.|Epic race tune|Rouge pulleys|Seibon CF hood|CSL bumper|ST-40|XR-2|SS lines|half cage|Recaro profi|Profi 2 harness|BMWpedals|BW studs|
1MOREMOD is online now   United_States
0
Reply With Quote
      11-01-2013, 06:43 PM   #11
M3PO
Colonel
 
M3PO's Avatar
 
Drives: '08 IB E92
Join Date: Sep 2011
Location: OC

Posts: 2,698
iTrader: (6)

I used 1L of SRF to flush the system.

No, changing the brake fluid will not purge the clutch system. It will still have old fluid in it. Flushing the clutch is very similar to flushing one of the calipers, only the bleeder is on the slave. It is VERY easy to introduce air into the clutch since the feed to the clutch master is high on the reservoir, and once you do, you will need a vacuum bleeder.

Ask me how I know.

Quote:
Originally Posted by apecush View Post
No. Once the fluid is opened, if it isn't in the brake system within a couple days, discard it.
I have always heard this but it seems like an urban legend to me. I know that brake fluid absorbs water. But if it is in a plastic bottle that is air tight, or very nearly so, the brake fluid can only absorb what moisture is contained in the air inside the bottle. Which is very little.

Even if the bottle is not completely air tight, there will be very little air exchange with the outside environment and next to no moisture will be introduced.

I mean think about it, the brake system is really no more air tight than the brake fluid bottle.
__________________
2008 IB E92 M3| BBS | KW | Arkym | Platte Forme A.G. | Active Autowerke | K&N | Fabspeed | Dinan | Evolve-R
M3PO is offline  
0
Reply With Quote
      11-02-2013, 05:37 AM   #12
BimmerRob08
Major
 
BimmerRob08's Avatar
 
Drives: 2008 M3, Space Gray
Join Date: Mar 2008
Location: KIKR (ABQ), NM

Posts: 1,255
iTrader: (0)

Quote:
Originally Posted by apecush View Post
No. Once the fluid is opened, if it isn't in the brake system within a couple days, discard it.
Is there a reason why? I'm not aware of one.

I have had to pump 3 lites before after I replaced a front/right AP caliper because there were air bubbles actually trapped. Had to do two flushes and then finally they let loose. I know 3L sounds alot but better to have it, not use it and return or save it (if unopened I guess now) rather than to run out and still have some bubbles trapped is my thinking.
BimmerRob08 is offline   United_States
0
Reply With Quote
      11-02-2013, 10:11 AM   #13
aus
Major General
 
Drives: Odysse
Join Date: Jul 2005
Location: Seal Beach, CA

Posts: 7,216
iTrader: (5)

Quote:
Originally Posted by M3PO View Post
I used 1L of SRF to flush the system.

No, changing the brake fluid will not purge the clutch system. It will still have old fluid in it. Flushing the clutch is very similar to flushing one of the calipers, only the bleeder is on the slave. It is VERY easy to introduce air into the clutch since the feed to the clutch master is high on the reservoir, and once you do, you will need a vacuum bleeder.

Ask me how I know.



I have always heard this but it seems like an urban legend to me. I know that brake fluid absorbs water. But if it is in a plastic bottle that is air tight, or very nearly so, the brake fluid can only absorb what moisture is contained in the air inside the bottle. Which is very little.

Even if the bottle is not completely air tight, there will be very little air exchange with the outside environment and next to no moisture will be introduced.

I mean think about it, the brake system is really no more air tight than the brake fluid bottle.
Especially if you're using SRF, which has a very high wet boiling point.

.
__________________
Let me get this straight... You are swapping out parts designed by some of the top engineers in the world because some guys sponsored by a company told you it's "better??" But when you ask the same guy about tracking, "oh no, I have a kid now" or "I just detailed my car." or "i just got new tires."
aus is offline  
0
Reply With Quote
      11-02-2013, 10:55 AM   #14
apecush
Lieutenant
 
Drives: 2008 E90 M3
Join Date: Aug 2011
Location: Edmonton

Posts: 430
iTrader: (2)

Quote:
Originally Posted by BimmerRob08 View Post
Is there a reason why? I'm not aware of one.

I have had to pump 3 lites before after I replaced a front/right AP caliper because there were air bubbles actually trapped. Had to do two flushes and then finally they let loose. I know 3L sounds alot but better to have it, not use it and return or save it (if unopened I guess now) rather than to run out and still have some bubbles trapped is my thinking.
brake fluid is hygroscopic, meaning that it absorbs moisture from the air. Once you crack the seal, you're on your way to the wet boiling point of the fluid. Over time, it absorbs more and more. The majority of brake fluid bottles will tell you to only use fluid from a sealed container.
apecush is offline  
0
Reply With Quote
      11-02-2013, 01:20 PM   #15
1MOREMOD
2014 Track Days - 6|Ridge 1:54:61|Pacific 1:35:72
 
1MOREMOD's Avatar
 
Drives: Race car->
Join Date: Mar 2009
Location: check your mirrors

Posts: 11,607
iTrader: (5)

Quote:
Originally Posted by apecush View Post
brake fluid is hygroscopic, meaning that it absorbs moisture from the air. Once you crack the seal, you're on your way to the wet boiling point of the fluid. Over time, it absorbs more and more. The majority of brake fluid bottles will tell you to only use fluid from a sealed container.
They also want to sell you more than you need. I continue to use open container for bleeds as the fluid in contact with heat is the same and gets removed. Having slightly lower boiling pt fluid in your master cyclinder is not going to matter.
1MOREMOD is online now   United_States
0
Reply With Quote
      11-04-2013, 07:50 AM   #16
BimmerRob08
Major
 
BimmerRob08's Avatar
 
Drives: 2008 M3, Space Gray
Join Date: Mar 2008
Location: KIKR (ABQ), NM

Posts: 1,255
iTrader: (0)

Quote:
Originally Posted by apecush View Post
brake fluid is hygroscopic, meaning that it absorbs moisture from the air. Once you crack the seal, you're on your way to the wet boiling point of the fluid. Over time, it absorbs more and more. The majority of brake fluid bottles will tell you to only use fluid from a sealed container.
I'm the master of the obvious sometimes I knew that, thank you!
BimmerRob08 is offline   United_States
0
Reply With Quote
      11-05-2013, 07:15 PM   #17
HP Autosport
BimmerPost Supporting Vendor

 
Drives: E82 1M
Join Date: Mar 2007
Location: Santa Barbara, AP, Brembo, GIAC, Koni, Ohlins, Quaife, Stoptech, Vorshlag

Posts: 10,891
iTrader: (29)

Quote:
Originally Posted by happos2 View Post
Easy question hopefully, how much new brake fluid do you need to do a full flush? RBF600 looks to come in 500ml so I and trying to decide how many bottles I need.

Thanks!
1 liter will be plenty to flush the whole system. For RBF600 you will need two bottles.
HP Autosport is online now   United_States
0
Reply With Quote
      11-06-2013, 07:53 AM   #18
happos2
Dingleberries
 
Drives: Gray E92 M3
Join Date: May 2012
Location: Indiana

Posts: 1,028
iTrader: (2)

Quote:
Originally Posted by HP Autosport View Post
1 liter will be plenty to flush the whole system. For RBF600 you will need two bottles.
Great! Thanks.
happos2 is online now  
0
Reply With Quote
      11-06-2013, 09:30 AM   #19
1MOREMOD
2014 Track Days - 6|Ridge 1:54:61|Pacific 1:35:72
 
1MOREMOD's Avatar
 
Drives: Race car->
Join Date: Mar 2009
Location: check your mirrors

Posts: 11,607
iTrader: (5)

Quote:
Originally Posted by HP Autosport View Post
1 liter will be plenty to flush the whole system. For RBF600 you will need two bottles.
Yeah voice of reason!
1MOREMOD is online now   United_States
0
Reply With Quote
      11-06-2013, 12:04 PM   #20
mid-corner fun
Major
 
Drives: e92
Join Date: Jun 2005
Location: NE

Posts: 1,376
iTrader: (3)

In addition to the 2 RBF bottles, buy an extra one and keep it aside/sealed. Mark the bottle so you use it during the next flush, cycle a newer bottle as the next backup.

If the flush goes wrong, chances are very low that you can find RBF600 locally.
mid-corner fun is online now   United_States
0
Reply With Quote
      11-06-2013, 12:21 PM   #21
happos2
Dingleberries
 
Drives: Gray E92 M3
Join Date: May 2012
Location: Indiana

Posts: 1,028
iTrader: (2)

Quote:
Originally Posted by mid-corner fun View Post
In addition to the 2 RBF bottles, buy an extra one and keep it aside/sealed. Mark the bottle so you use it during the next flush, cycle a newer bottle as the next backup.

If the flush goes wrong, chances are very low that you can find RBF600 locally.
That makes sense...nothing wrong with having a little extra around incase I screw up. Thank you for the comment.
happos2 is online now  
0
Reply With Quote
      01-01-2014, 10:00 PM   #22
Foozed
Enlisted Member
 
Drives: 2012 e92 M3
Join Date: Dec 2013
Location: Raleigh

Posts: 46
iTrader: (0)

When flushing before DE events a very seasoned Viper driver told me it wasn't necessary to flush all fluid but only the burnt/dis colored stuff that's near the calipers so I'd only use 1 bottle each time I did this on my cayman R.
Any opposing thoughts on that one?
Foozed is offline  
0
Reply With Quote
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 02:12 PM.




m3post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST