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2006 650i Black Sapphire Metallic
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Discussion Starter · #21 ·
Well, I'm into it now! :)

Has any done this master cylinder replacement? I'm at a bit of an impasse here. I did a bench bleed but to install it you have to remove the reservoir and tilt the cylinder to insert it into the booster. That seems to negate value of the bench bleed - and get brake fluid all over the compartment. Hopefully I've cleaned that up with a minimum of paint damage.

The instructions just say install it, then fit the reservoir and bleed the system. Everything else online says to do a bench bleed of a master first. Did I waste my time doing that and will pressure bleeding eliminate/minimize any problems due to not bench bleeding first?

Any prior experience would be useful.
 

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2006 650i Black Sapphire Metallic
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Discussion Starter · #23 ·
Thanks. I have that and was using it as my guide along with some YouTubes and prior experience. The instructions with the new master say to bench bleed it first, Other posts about soft brakes and bleed issues also question the OP on whether a bench bleed was done.

I figured better too much bleeding rather than too little but now it seems like that was counterproductive and I'm just trying to be sure that it isn't me. I'd hate to get this all bolted back in and find out that even pressure bleeding will not clear bubbles in the master.

Waiting for the pressure bleeder to be delivered sometime in the next 4-6 hours, according to Amazon and UPS. I'm traveling tomorrow so if it isn't delivered soon it will have to wait a few days.
 

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You probably also have the attached TIS document on "bleeding the brakes with the DSC". I think that if TIS doesn't mention a "bench bleed", then surely it isn't required. I have never used the BMW Diagnosis and Information System (DIS) software. If you have DIS you should be good.
 

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The only thing I can think of for a reason to bench bleed would be to pre-lubricate (with brake fluid) some stuff inside the new master cyl. no matter what, after opening the system this far, it would seem you are going to need a full on bleed. if you don't already have them, they make silicone stoppers of various sizes that work great to seal off things like brake lines while you perform work.

I'm not quite following this part, about brake booster must be loosely screwed into place? what screws are they referring to?

1036833
 

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2006 650i Black Sapphire Metallic
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Discussion Starter · #26 ·
Bench bleeding usually eliminates a significant amount of air from MC prior to the bleed process on he car. If it wasn't for having to remove the reservoir to install the MC it would have been useful. Also, I bought a MC with a reservoir thinking that would be more reliable as an assembly but that turned out to be a waste of money. Since the reservoir has to come off anyway you might as well re-use your old one as long as it is OK.

The space for the MC and booster is pretty tight and you have to tilt the booster up and away from the firewall a bit to remove the MC from the mounting bolts on the booster. Same to reinstall it and be sure that the pedal rod through the booster is properly aligned inside the MC piston.

I never removed the booster nuts completely, which are inside the firewall by the pedal. I removed the clip and pin and just loosened the nuts most of the way on the bolts to give some slack on the booster. It is important to know that the pin has a second clip attached to it that clips on the pedal rod. It is hard to see the pin and you have to work by feel and it took me a while to figure out why I couldn't push the pin out after removing the end clip shown in the instructions. You just have to rotate the pin to unclip if from the rod.

I tried to pressure bleed the system after the install but that isn't working properly. With 20 psi pressure I got a little flow out of the right rear bleed valve but then nothing, Same for the left rear. Pressure holding at 20 psi on the MC and bleeder open but nothing coming out! I know that the bleed valves are not blocked because I did the brake fluid flush a week ago using my vacuum bleeder and had no problem on any wheel. I was traveling yesterday and today (still away) so I had to put a hold on this. Hopefully back at it tomorrow.

I have figured out where in INPA to run the DSC/ABS bleed procedure. One minor issue is that INPA says that you must do this is the following order: "Bleed HL", "Bleed VL", Bleed VR", "Bleed HR". It looks like L and R are left and right and "V" is for "Vorderseite" which Google Translate says is Front. I'd be more confident if I could find a German word that starts with "H" that was related to rear, back, aft, etc., but there isn't one. So the sequence seems to be rear driver, front driver, front passenger, rear passenger. I find that a little surprising.

That's where I am right now. I've been taking pictures so I'll try to write this up when I'm finished.

If anyone happens to be sure on the wheel positions stated in INPA I'd appreciate knowing.
 

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One minor issue is that INPA says that you must do this is the following order: "Bleed HL", "Bleed VL", Bleed VR", "Bleed HR". It looks like L and R are left and right and "V" is for "Vorderseite" which Google Translate says is Front. I'd be more confident if I could find a German word that starts with "H" that was related to rear, back, aft, etc., but there isn't one. So the sequence seems to be rear driver, front driver, front passenger, rear passenger. I find that a little surprising.
Your question is answered here:
Master Cylinder to ABS Pump Line Locations

"The embossed marking is German language
H = Hinten = rear
V = Vorne = front
HR = Hinten Rechts = rear right
HL = Hinten Links = rear left
VR = Vorne Rechts = front right
VL = Vorne Links = front left"

The TIS instructions say to perform in this order: rear right, rear left, front right, front left
This makes sense to me, since it is "longest line" first, "shortest line" last.
Maybe you do the "rear left" first for a European car with "right hand drive"?
 

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Your question is answered here:
Master Cylinder to ABS Pump Line Locations

"The embossed marking is German language
H = Hinten = rear
V = Vorne = front
HR = Hinten Rechts = rear right
HL = Hinten Links = rear left
VR = Vorne Rechts = front right
VL = Vorne Links = front left"

The TIS instructions say to perform in this order: rear right, rear left, front right, front left
This makes sense to me, since it is "longest line" first, "shortest line" last.
Maybe you do the "rear left" first for a European car with "right hand drive"?
Spot on, but, you'd only reverse the sides for right hand drive cars as Europe has both left and right hand drive, basically though your reasoning is bang on (y).
 

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Michael
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You always bleed from furthest to the shortest distance from the master cylinder. If you have a pressure system for a positive bleed you will have no issues, however as you are replacing the master cylinder this would not be practical, so ensure you have enough fluid available to continue through till you reach the point of zero air in the system
 

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Discussion Starter · #30 ·
Thanks for the clarification. My search missed that post. For fun, do a Google Translate from English to German of "rear" and see what context it shows for Hinten

I agree with the longest to shortest bleed order but here is the INPA page. (I have no indication that this is a UK version of INPA.) The order given shows the rear wheels being first and last. Those can't be the longest and shortest in either LH or RH drive vehicles

1036907


I can't imagine that it would be a problem to start with F4 then F1 > F2 >F3 and worst case do the sequence twice. At least now I'm sure of which wheel valve to open for each step.

I'm not clear on this statement, "If you have a pressure system for a positive bleed you will have no issues, however as you are replacing the master cylinder this would not be practical,..." Why isn't the pressure bleeder practical? Actually I would think that it would be help keep the fluid level correct if I fill it with two liters of brake fluid before I start.

I'm home now so back at it later today..
 

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Michael
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If you change the master cylinder unless you can pinch the brake line? Which I believe is metal tube so you cannot use a pinch tool, then when swapping over the parts, you must let air into the system, which is why the mention bench bleeding, to limit the potential for lots of air in the system. Changing the MS means that you cannot keep the system sealed against air getting in, which is one of the primary benefits of a pressure system when bleeding brakes when changing fluid. I have never done the repair but it seems logical, plus the more air you are trying to remove generally means the use of more fluid, even with a pressure system??? I use a snap on tool kit for this so only need myself the change fluid and bleed the system! I would not like to think I am mis-guiding you !
 

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After changing my calipers, think I went thru 3L of fluid - its in the link I posted earlier.
 

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Discussion Starter · #33 ·
I'm still not clear on why pressure bleeding won't work. Of course I have let air in the system when I installed the MC. I did a bench-type bleed once it was on the car by using the included plastic plugs with hose barbs on the mating ends of the short connector pipes and clear tubing back into the reservoir. I pumped out most of the air this way before I connected the short metal pipes to the main brake lines. But even if it is a lot of air, I would still think pressure bleed would eventually get it all out.

Now that this is done I would expect that I could pressure bleed the system through the MC. That is what doesn't seem to be working. I'm going to try the INPA DSC bleed procedure and see if that helps.

3 liters it is. Thanks, I didn't notice that it but you can't be too prepared. It does seem like a lot.

Hope to get to it on Saturday.
 

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I was also doing a full flush at the time, since you already did that, you may need less.
 

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Michael
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I am not saying using a pressure bleed system wont work at all, in fact it will be a great tool to use!! I am pointing out that subject to how much air gets into the system will dictate the need for enough fluid to keep on top of ensuring the it does not empty when you are bleeding the brakes at each point. I am sure you will get it done easily
 

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I've got to do this soon, Can anyone indicate which version of INPA you need to have that Function?
I'm running 5.0.6 with E60 V1.26 but don't have the ABS module listed and it doesn't seem to be in the DSC one.
 

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If you got air in the system, you will need to use INPA or ISTA to bleed the brakes.
Why is that Herb? I thought all INPA does is activate ABS?
 

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Discussion Starter · #39 ·
I've got to do this soon, Can anyone indicate which version of INPA you need to have that Function?
I'm running 5.0.6 with E60 V1.26 but don't have the ABS module listed and it doesn't seem to be in the DSC one.

I'm running the same version and the brake bleed routine is under DSC E60-16. It give errors about language and version mismatch but if you click OK you will get to the screen where you can chose Activate and run the sequence, maybe!

I have run into a problem with the bleed routine. It runs the pump with the brake off and then tells me to actuate the brake, which I do, but it never sees the brake activation. The brake lights come on so I know the switch is working but it doesn't see them. It also throws an EDIBAS script error.
1037046


This may have to do with the version mis-match but I'm not sure what to do about that.

Time for some more research and/or try to get ISTA running. Right now it seems that this MC replacement has become a lifetime project. :)
 

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Why is that Herb? I thought all INPA does is activate ABS?
INPA, or TIS will show the directions for the brake bleed. I don't use INPA a lot, but there should be a way. TIS is pointing to DIS, but not a lot of people can load & run DIS. In ISTA the bleed procedure should be run under service functions. If you have a pressure bleeder, this will be much easier.

The described procedure is compulsory for the E83 R L due to the line arrangement between tandem-brake master cylinder and DSC unit. This brake venting procedure can also be carried out in the event of problems with venting the brake system on the E83 LL and E60.


Control lines: The so-called control lines (connecting leads between tandem-brake master cylinder and DSC unit) on the E83 RL cannot be bled in the conventional manner using the brake fluid replacement device. The cause of this is the large line diameters and the line arrangement. With this special venting routine, brake fluid and enclosed air are pushed towards the brake calliper.


Primary circuit: In the DSC unit, air bubbles can stick to the edges and valves. The vibrations that occur during venting with the DIS tester /GT1 loosen the air bubbles.


Secondary circuit: Normally (DSC not active), the secondary circuit of the DSC unit is closed. Air contained in it cannot escape during venting with the brake fluid replacement device. The pump and inlet/outlet and high-pressure switch valves are activated using the DIS Tester / GT1. This also vents the secondary circuit.


Following replacement and repair of the following parts, the DIS tester /GT1 must be used for venting:


-Hydraulic unit
-Master brake cylinder
-Components and/or connecting lines located between the hydraulic control unit and master brake cylinder

Operations:


The order of the operation must be adhered to without fail:
rear left (RL), front left (FL) front right (FR) rear right (RR)


  1. Connect the brake fluid replacement device and switch
    online;(The fill pressure must not exceed 2 bar)
  2. Vent control line of rear axle brake circuit:
    -Attach the venting bottle to the RL vent valve
    -Open the RL vent valve
    -Start the brake venting procedure (inspection step: ”Vent rear axle brake circuit”)
    Caution:
    do not press the brake pedal!
  3. Vent RL brake hose:
    -The RL vent valve remains open
    -Continue brake venting procedure (inspection step: ”Vent RL brake hose”)
    -Pump the brake pedal while the routine is running:

    • Press the brake pedal firmly as far as it will go
    • Hold the brake pedal for 4 to 5 seconds
    • Let go of the brake pedal
    Approx. 6 pump operations in 30 seconds.
    Finish the pump operation when bubble-free brake fluid flows out. If necessary, continue pressing the brake pedal, i.e. more than 6 operations and longer than 30 seconds
    Note:
    brake pedal resistance changes depending on the valve switching operations and the running pump. The brake pedal is still to be operated as described.
    -Close the RL vent valve
  4. Vent control line of front axle brake circuit:
    -Attach the venting bottle to the FL vent valve
    -Open the FL vent valve
    -Continue brake venting procedure (inspection step: ”Vent front axle brake circuit”)
    Caution:
    do not press the brake pedal!
  5. Vent FL brake hose:
    -The FL vent valve remains open
    -Continue brake venting procedure (inspection step: ”Vent FL brake hose”)
    -Pump the brake pedal while the routine is running:

    • Press the brake pedal firmly as far as it will go
    • Hold the brake pedal for 4 to 5 seconds
    • Let go of the brake pedal
    Approx. 6 pump operations in 30 seconds.
    Finish the pump operation when bubble-free brake fluid flows out.
    -Close the FL vent valve
  6. Vent FR brake hose:
    -Attach the venting bottle to the FR vent valve
    -Open the FR vent valve
    -Continue brake venting procedure (inspection step: ”Vent FR brake hose”)
    -Pump the brake pedal while the routine is running:

    • Press the brake pedal firmly as far as it will go
    • Hold the brake pedal for 4 to 5 seconds
    • Let go of the brake pedal
    Approx. 20 pump operations in 100 seconds.
    Finish the pump operation when bubble-free brake fluid flows out.
    -Close the FR vent valve
  7. Vent RR brake hose:
    -Attach the venting bottle to the RR vent valve
    -Open the RR vent valve
    -Continue brake venting procedure (inspection step: ”Vent RR brake hose”)
    -Pump the brake pedal while the routine is running:

    • Press the brake pedal firmly as far as it will go
    • Hold the brake pedal for 4 to 5 seconds
    • Let go of the brake pedal
    Approx. 20 pump operations in 100 seconds.
    Finish the pump operation when bubble-free brake fluid flows out.
    -Close the RR vent valve
    -Switch off ignition, wait 10 seconds, switch ignition on again. This also ensures that the activation routines are terminated.
  8. Remove the brake fluid replacement device

Note:


A second person is required for this task
 
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