Any ABS places to drain brake fluid 94 RS

[jagarra]

I am in the process of doing the major maint. on my new to me 94 R1100RS. I am draining the brake fluid using a Mityvac unit pulling the fluid from the calipers to drain the system, pretty gross looking fluid. I guess my concern is how about all that plumbing going to and from the ABS unit, how does that get drained??

 

[PGlaves]

Bleed nipples on the ABS unit under the tank. I usually bleed here first, and then at the calipers.

 

[jagarra]

Thanks, I will look for them, tank off waiting for new vibration pad for fuel pump, should be piece of cake, if I can see them.

I guess I found them, two rubbers caps hiding them right in the center on top. Didn't get much fluid, now when I pump it up and open a bleed screw it holds vacuum, no more fluid.
I am changing all the brakes lines to units from Spiegler so when I start to fill the system does one start the air bleed from the highest point on the ABS, then work the calipers?

 

[m_stock10506]

The ABS-II plumbing is one continuous fluid line from the master cylinder to the caliper, with the ABS hydro unit sitting in the middle (one for the front, one for the rear). If you pump enough fluid through the line, you will bring the new brake fluid that you put into the master cylinder all the way to the caliper. The two bleed valves on the ABS unit will let you draw off any fluid that was hiding in a nook there and didn't get swept along in the regular bleed.

The ABS-II system is so easy to bleed that I do mine at least once a year, sometimes twice. Since the fluid going through is so clean I only bleed from the ABS unit every 2nd or 3rd bleed - and the fluid is also very clean there too.

 

[jagarra]

Since this fluid has not been changed for many, many years based on the color (dark brown to black) I guess I will will just pull lots of fluid through from the ABS first, then from the calipers. This, I hope, will satisfy the system and shut the ABS light off, as it was flashing when I rode it home from the sale.

 

[BC1100S]

Since this fluid has not been changed for many, many years based on the color (dark brown to black)....

I trust the bike does not still have the original rubber brake lines. if it does, replace those with braided steel ones before you do anything else.

 

[PGlaves]

I trust the bike does not still have the original rubber brake lines. if it does, replace those with braided steel ones before you do anything else.

See Post#3, paragraph 2.

 

[BC1100S]

See Post#3, paragraph 2.

Doh!

 

[gsaddict]

I am changing all the brakes lines to units from Spiegler so when I start to fill the system does one start the air bleed from the highest point on the ABS, then work the calipers?

Once the new lines are installed, I push the fluid up from each caliper with a syringe. Air bubbles go up much easier than down. Once the reservoir is full then I bleed thru with vacuum first to the bleed nipple on the ABS modulator and then to the caliper.

 

[jagarra]

Interesting set up there. What is that little unit in the yellow line, a check valve? I have some syringes left over from the vet for my cats, increasing air dissipation always good.. Got me wondering if a MityVac can be used with it's pressure port pushing fluid out of the catch pot? If you didn't have a check valve I guess you could open the bleed port, press the device to inject fluid, then close the port to sort of re-cock your device and repeat.

When I bled the system, I was surprised on how little fluid was in there, front master was to the fill line, rear was down about 3/4.

 

[gsaddict]

Interesting set up there. What is that little unit in the yellow line, a check valve? I have some syringes left over from the vet for my cats, increasing air dissipation always good.. Got me wondering if a MityVac can be used with it's pressure port pushing fluid out of the catch pot? If you didn't have a check valve I guess you could open the bleed port, press the device to inject fluid, then close the port to sort of re-cock your device and repeat.

When I bled the system, I was surprised on how little fluid was in there, front master was to the fill line, rear was down about 3/4.

Not a check valve, simply a shutoff so the fluid doesn't dribble out when not connected.