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Discussion Starter #1
Today I put a refurbished ABS pump back in place of a 2002 LT of a friend of mine. I bleeded the brake circuits as followed (and according the cycle: pull the brake, valve open, valve closed, loosen the brake)

1. from the front brake to the pump on hand pressure
2. from the rear brake to the pump on hand pressure
3. from the pump to the rear brake caliper with the ignition on and using the abs pump itself
4. from the pump to the front calipers with the ignition on and using the abs pump itself

The brakes are working fine with no ABS errors. The rear brake is superb. However, the hand brake can still be squeezed into the handle.

On this forum I got the advice to put tie-rips to the front brake and a strap on the rear pedal for a night or so. Will do that but I have the followinhg questions:

- is air in the circuit the reason that I can squeeze the hand brake that far?
- What else can I try to get the last air out?

Sorry for my bad English. I'm from the Netherlands. :D
 

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Wrencher Extraordinaire
2005 K1200LT
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Yes there is air in the system. You need to bleed three ports on the ABS unit in sequence. On the picture you want to pull fluid from F1 F2 F3 and F1 a second time. That should get all the air out. Also it is up hill to the reservoir so the strap on the lever with bar turned may also fix the air in the lines. No need to do anything with the pedal. You will be able to pull the lever to the bar with the key off. But you should not be able to do it with the key on (feedback from the powered ABS). Your English is just fine, way better than my Dutch!
 

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Discussion Starter #3
Great picture. thanks!

Two questions:

I'm not sure where the F2-port is located. Is it on the pump or do you mean the calipers?

Second question is how do i put pressure while bleeding the F1-port? Or is it enough just to open it?
 

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Hello

The 3 bleeders F1, F2, F3 are on the ABS unit.
You should bleed the three of them if you suspect some air bubbles in the front control circuit.


Bruno
 

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Great picture. thanks!

Two questions:

I'm not sure where the F2-port is located. Is it on the pump or do you mean the calipers?

Second question is how do i put pressure while bleeding the F1-port? Or is it enough just to open it?
I think you should watch kirks utube on bleeding brakes, it looks like you need a bit of help
 

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Discussion Starter #6
i've watched the Kirk-videos many times. That's how I came so far bleeding the brakes.

Correct me if i'm wrong but in the videos I only see him using R3 and F3.
That's why I was confused about the other ports.

But maybe I missed another video of him. I will go and check the Illinois-site.
 

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Discussion Starter #7
I think I know what's going on:
Kirk is displaying a flush when no air has entered the system.\

But when you change the pump or the lines, you have to use the other ports as well.

I'll give it a try this weekend!

:wave
 

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I think I know what's going on:
Kirk is displaying a flush when no air has entered the system.\

But when you change the pump or the lines, you have to use the other ports as well.

I'll give it a try this weekend!

:wave
This assumption is correct. Any major surgery like change of brake hoses or the removal-install of ABS unit will require a complete bleed (a lot of air is trapped). If you had been using the BMW factory shop manual (avail on CD) this is clearly documented.

Another technique covered in BMW shop manual is to use pressure, like a large syringe, to push fluid back from the ABS-unit toward the master cylinder (Front Control circuit using LONG bleed port F3). When air bubbles do not go down (toward ABS-unit), they will go up easier - note that ignition is always OFF as you are working only on control-circuits at this point.

P.S.: To answer your last question: the F2 port is hidden on the other side of the ABS-unit, at same position of R2, but opposite side.
 

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sounds like you have it sussed out, I pushed mine out of the shed and gave it a good hose down with water, (not pressure washer) to remove any spilled brake fluid before putting it back together
 
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