Brake fluid flush with ABS

[Camshaft]

I'm wondering what the general concensus is for bleeding BMWs with ABS. I was wanting to use a pressure bleed (not vacum) and was wondering what companies had a fitting that would work with the master. If nothing else, im gonna try to find an extra master cover with diaphram and drill a hole for a pressure fitting.

Any ideas, recommendations or suggestions?

Anyone think bleeding with the lever is sufficient/even possible with ABS?

Thanks for any responses in advance.

[BubbaZanetti]

i bled my brakes not 2 days ago and did it "the old fashioned way" (albeit with my nifty new speed bleeders) and have been told by several reliable sources that done yearly this is fine, since the system is looped and the ammount of fluid in the abs area (under the tank) is small. i highly recommend the speed bleeders, i did all my brakes in under a half hour, although getting the factory vacuum adapter off the right front caliper is a bear, it feels like you're stripping it out cause of the loctite

[Camshaft]

Just to clarify, your old fashioned method with the speed bleeder consisted of a vacum style bleeding (i.e. connecting at the bleeder valves and refilling master as needed)?

Or am I missunderstanding you? :dunno

Old fashioned to me is the pump up-hold down-open valve (while pulling lever down) -then close valve, repeat process until renewed.

[bmwmick]

I'm wondering what the general concensus is for bleeding BMWs with ABS. I was wanting to use a pressure bleed (not vacum) and was wondering what companies had a fitting that would work with the master. If nothing else, im gonna try to find an extra master cover with diaphram and drill a hole for a pressure fitting.
Any ideas, recommendations or suggestions?
Anyone think bleeding with the lever is sufficient/even possible with ABS?
Thanks for any responses in advance.

Luft,
It sort of depends on what generation of ABS you are talking about. If you have ABS-I or ABS-II, you can bleed the brake system 'the old fashioned' way. :) I use a vacuum bleeder at the calipers on both my ABS-I and ABS-II systems.

If you use the "lever pump" method to build pressure in the system and then bleed the system at the calipers, don't pull the lever all the way back to the bar. This makes the piston travel past the normal point of operation. Just tape a block of wood or something tothe handlebar 1/4" thick or so, to keep the piston away from the 'uncharted' area. I've known several folks who have ruined a master cylinder piston by forcing the piston all the way during a brake bleed.

If you have I-ABS (Integrated ABS with the servo motors) there are several good write-ups on bleeding this system too.

[1flyer]

Like Mick said, it all depends on what bike you have and what system you are using. Some systems aren't any problem and other systems are not for the un-informed. There have been questions asked about "why didn't the fluid level drop in the reservoir when I opened the bleeds". Anyone can give you their answer about how they did their brakes but the only real answer to your question depends on what you have and whether you can do it or not depends on your understanding of how your system operates. You're a BMW service advisor, what are you looking for?

[BubbaZanetti]

Old fashioned to me is the pump up-hold down-open valve (while pulling lever down) -then close valve, repeat process until renewed.

yep, this is what i'm talking about, no vacuum pump, just repeatedly squeezing the lever (no need to "close valve" w/ the speed bleeders) till you process all the fluid through the system

[MCMXCIVRS]

I've always done mine on my 94 RS the old fashioned way too. I have even done it this way after having replacing the lines with stainless ones with no trouble. You do need to bleed at the servo if you get air in the system, otherwise, just at the calipers. It works just fine and requires no investment in fancy adapters or expensive equipment. I use a plastic jar with a hole drilled in the lid and a length of tubing that slips over the bleeder nipple to catch the old fluid. I use a turkey baster to suck most of the old fluid out of the resevoir first, then refill with fresh fluid to start flushing. This minimizes the amount of pumping to get rid of the old stuff. I also drape a wet towel on any painted parts within dripping range to soak up any errant fluid.

[Camshaft]

You're a BMW service advisor, what are you looking for?

For cars, not bikes, besides all the techs here have HDs. Bleeding brakes w/ABS systems on cars is a no-brainer, even on the illustrious 745/760LI :sick

I've bled brakes using several methods and was just wondering what the best was for this particular application, I guess there is no clear-cut best method. I think I'll just get the master covers and drill em and then use a pressure fitting. BTW this is a 95rs.

More than anything I was just curious about results using the various methods and peoples feedback.

Thanks.

[boomyr]

I've been a little wary to flush the brakes on my '96 K11RS after reading this warning in my CLYMER K-SERIES 1985-1995.

On page 473 for those of you that want to read along:


NOTE - Bikes equipped with the ABS system [B]must[B] have the system bled by a BMW dealer using a power brake bleeder unit. This is necesary due to the number of pipes and hoses and the volume of brake fluid used with this system. It is impossible to remove all air bubbles from this system with hand bleeding, even using the hand-operated brake bleeder shown in this procedure for non-ABS models


On the other hand, I've read numerous post on here by several people that I believe are knowlegable, that have done it themselves no differently than they would bleed a non ABS bike.

So I tend to believe that it's not such a big deal.


I guess what would be helpful know is :

1. What DO you need to do differently, if anything?

2. What to be careful of?

3 Whats the WORST case senario if you screw it up? (Rebleeding vs. screwing up the whole system $$$ :doh$$$:cry $$$)

[boofer]

Someone correct me if I'm wrong......when using the mighty vac, it seems to get the air out without much fluid in the process. Great for bleeding, but for flushing, no.

I saw an artical somewhere on making a pressure bleeder with a garden sprayer. Quite nice, had it saved in "favorites" before my HD pucked. I'll look for it.

Tim

[boofer]

http://www.apexcone.com/JimPowellHomepage/Bleeder/bleeder.html

[BubbaZanetti]

500 miles since brake bleed, no noticable differences, seems to work fine with the standard "open valve, pump lever" method

[Kenny2]

Try this site for information on bleeding ABS brakes.
Brake Bleed (http://www.beachbus.net/BMW/)
Hopefully it fits your needs.

[110997]

I just bled my front brakes after an install of a new front MC. I used the mighty vac. to get the old fluid out, once the clean started flowing; I used the speed bleeders to finalize it. 15 minutes total! ABS is working great; it kicked in a couple of times as needed within 20 miles after bleeding.

Good luck

Derek