[OGOverkill]

is there any information on what pressure to run with the Motive bleeder? I have one that i use for my Focus RS, but the manual specifies what PSI is recommended.

[Ximian]

Originally Posted by OGOverkill

is there any information on what pressure to run with the Motive bleeder? I have one that i use for my Focus RS, but the manual specifies what PSI is recommended.

You can go higher but I don't exceed 15 PSI for any of my cars.

While your lines and hopefully all the o-rings sealing up the brake system can handle more, higher pressures aren't great on the power bleeder itself.

[markoz28]

Originally Posted by OGOverkill

is there any information on what pressure to run with the Motive bleeder? I have one that i use for my Focus RS, but the manual specifies what PSI is recommended.

15PSI

[amajer]

Castrol SRF flush with the motive bleeder. No battery disconnect. No warning lights after start up. Felt stupid but realized you must push the handle all the way down and lock it into place on the bleeder. After that got all the air out of the system very easily. Also quickjacks for the win!

Update: 9/22/24
Autocross this past weekend, first hard driving after the flush and had zero issues.

[stark_c]

Originally Posted by amajer

Castrol SRF flush with the motive bleeder. No battery disconnect. No warning lights after start up. Felt stupid but realized you must push the handle all the way down and lock it into place on the bleeder. After that got all the air out of the system very easily. Also quickjacks for the win!

Update: 9/22/24
Autocross this past weekend, first hard driving after the flush and had zero issues.

I’m curious, is the brake pedal on G80 supposed to firm up when car is off?

Does your brake pedal make wooshing sound when you press it when car is off? Like mine does it in this post I made: https://www.bimmerpost.com/forums/sh...php?p=31499166

[shawnhayes]

Originally Posted by stark_c

I’m curious, is the brake pedal on G80 supposed to firm up when car is off?

Does your brake pedal make wooshing sound when you press it when car is off? Like mine does it in this post I made: https://www.bimmerpost.com/forums/sh...php?p=31499166

Neither my G80 or my G82 firms up like older cars when car is off.

Thought my butt was going to swallow the seat when it happened first time I bled the brakes. Thought I broke the car.

I'm not hearing the wooshing sound you're speaking of. (I only have laptop speakers)

Shawn

[stark_c]

Originally Posted by shawnhayes

Neither my G80 or my G82 firms up like older cars when car is off.

Thought my butt was going to swallow the seat when it happened first time I bled the brakes. Thought I broke the car.

I'm not hearing the wooshing sound you're speaking of. (I only have laptop speakers)

Shawn

Thanks for the reply!
I think I attached the wrong link, here is the correct video: https://youtube.com/shorts/6b6dW2K03...19n4UrFFu6KOop
Could you take a look?
Many thanks!

[godunovs65]

Originally Posted by B_davis

Just did a full flush on all calipers with pressure bleed and no battery disconnect. No Issues

Disconnect the battery if you want to bleed the fluid in the ABS pump. With battery connected it will remain locked inside the pump. Disconnect and wait 30 minutes (or an hour, if you have time), the ABS pump will open, then bleed.

[godunovs65]

Originally Posted by stark_c

I’m curious, is the brake pedal on G80 supposed to firm up when car is off?

Does your brake pedal make wooshing sound when you press it when car is off? Like mine does it in this post I made: https://www.bimmerpost.com/forums/sh...php?p=31499166

The brake pedal must become stone solid after a few pumps when the car is off. That means you bled the system well and all valves are tightened well. If you feel sponginess - lift it again and bleed all around.
And it absolutely must make hissing sound. The air inside the brake booster does that.

[hockeygoalie35]

Originally Posted by godunovs65

Disconnect the battery if you want to bleed the fluid in the ABS pump. With battery connected it will remain locked inside the pump. Disconnect and wait 30 minutes (or an hour, if you have time), the ABS pump will open, then bleed.

Just curious do you have a source on this, or how can you tell? About to attempt my brake bleed Friday.

[godunovs65]

Originally Posted by hockeygoalie35

Just curious do you have a source on this, or how can you tell? About to attempt my brake bleed Friday.

I read about it a long time ago and tried on multiple cars. Recently, on a Lexus, disconnected the battery, waited 1 hour thinking it'd open by then, started bleeding, and then it opened when I was on the last caliper. I had to bleed all four again twice before all air came out. Alternatively, if you have a scan tool, you can activate the ABS valves from the tool (with battery connected, of course). Normally, I don't disconnect the battery and flush the fluid with the ABS locked. But if it's DOT 5.1 I would flush it entirely (which I did) annually (it got old pretty soon).

[codean]

hockeygoalie35

I don't know if I would take godunovs65 advice as fact. The statement of "I read about it a long time ago" leads me to believe that this was before "brake by wire" systems existed.

There is a lot more going on then just dealing with ABS valves in the new systems that are currently being used.

Originally Posted by godunovs65

The brake pedal must become stone solid after a few pumps when the car is off. That means you bled the system well and all valves are tightened well. If you feel sponginess - lift it again and bleed all around.
And it absolutely must make hissing sound. The air inside the brake booster does that.

Current M3/M4's don't have a brake booster with "air inside of them". There is no vacuum booster (which would be the noise of absence of air, but that's beyond the point). You are giving dated advise that doesn't apply.

[godunovs65]

Originally Posted by codean

hockeygoalie35

I don't know if I would take godunovs65 advice as fact. The statement of "I read about it a long time ago" leads me to believe that this was before "brake by wire" systems existed.

There is a lot more going on then just dealing with ABS valves in the new systems that are currently being used.



Current M3/M4's don't have a brake booster with "air inside of them". There is no vacuum booster (which would be the noise of absence of air, but that's beyond the point). You are giving dated advise that doesn't apply.

And one doesn't bleed the booster. Air inside the ABS pump is what I said. You're quite correct, my advice only applies to hydraulic brakes with a master cylinder with a brake booster. not brake by wire. Thanks for pointing that out.

[hockeygoalie35]

codean

Yes, I was a bit skeptical as well and I pulled up ISTA+ procedure, plus the TIS manuals during my bleeding. A couple things:

1. You definitely need to use the service function to open the ABS system. The ABS system comes prefilled from the factory, leading to my second point.

2. ISTA makes it very clear: You don't need to do an ABS bleed UNLESS you replace mechanical components such as the master cylinder. It specially mentions that a standard pressurized bleed is more than sufficient for the service interval.

This leads me to believe that Stealers likely don't do this during the 2 year bleed interval. I did a normal brake bleed with a power bleeder and everything went fine. Just removed the old fluid from the reservoir, topped it off with new, and put the rest of my 2L in the power bleeder. 6 bleeds later (2 on each front caliper), and done.

[codean]

Originally Posted by hockeygoalie35

This leads me to believe that Stealers likely don't do this during the 2 year bleed interval.

Some do... some don't, but they are suppose to.

The only way of getting all the old brake fluid out is to run the brake fluid renewal test plan which pumps out the old fluid, opens and closes all the valves that are in the system and finishes with a system pressure check at the end. General 2 year brake service, it's not all that important to do. How important is it to get every little last drop of the old fluid out, let say if you were upgrading fluid or the old fluid happened to boil? Hard to say, there can't be much fluid in those passages inside the integrated brake system. Better safe than sorry with brakes though.

[hockeygoalie35]

Originally Posted by codean

Some do... some don't, but they are suppose to.

The only way of getting all the old brake fluid out is to run the brake fluid renewal test plan which pumps out the old fluid, opens and closes all the valves that are in the system and finishes with a system pressure check at the end. General 2 year brake service, it's not all that important to do. How important is it to get every little last drop of the old fluid out, let say if you were upgrading fluid or the old fluid happened to boil? Hard to say, there can't be much fluid in those passages inside the integrated brake system. Better safe than sorry with brakes though.

I guess the only way to know for sure,is how much fluid you get billed for. Since the service function calls out a bleed before during and after.