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Discussion Starter · #1 ·
I just replaced all the brake fluid in 2 cars using Motive pressure bleeder. I hoped to achieve a firmer brake pedal in our van and just change the fluid in the bimmer. Everything went well but the pedal in the van is still spongy and the brake pedal in the bimmer became just a little less firmer than it used to be...:dunno:

My question is: is the flushing with Motive supposed to bleed the brakes too or do I now need to use the pump and hold method using a helper?

I really hoped that Motive would be the all in one solution to brakes flushing and bleeding but alas...
 

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Freude am Fahren
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It's all BMW uses ( well their machine is a little fancier). Did you let the level drop too far?
 

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Freude am Fahren
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That's a tonne. I used 750mL in both a 528 and a 540, colour change was definite. Used super blue, so it was quite obvious.

Tighten your bleeder screws. I didn't torque them fully; pedal was awfully spongy!
 

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It's supposed to be firmer. I have had nothing but success with the Motive power bleeder I bought. It basically has paid for itself many times over. I have done 3 non-BMWs with it and a BMW. I am about to do it again soon from a clutch job and caliper rebuilds. :thumbup:
 

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Discussion Starter · #8 ·

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Is it Trackday yet?
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Here's what I do instead of get a helper... I credit Ffej for this technique...

Refill reservoir (not bleeder), pressurize, crack open the bleeder screw and rush into the driver seat and pump the pedal 6-10 times vigorously and quickly. Run back and close bleeder screw, rinse and repeat on each corner. This will force air bubbles out that bleeding alone will not. 25psi isn't enough to cut bubbles loose. It is enough to keep the system pressurized so that when the pedal is returning to it's at-rest position, it will not suck dirty fluid back in at the caliper, or will it take air in. Be sure catch can/hose is submerged at the wheel too.

When working on the front, reduce the pump count as you will go thru the fluid much faster than you will in the rear. Do not let it get too low.
 

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Seek to understand,^Value
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See the part in red which should apply equally well to the E46 ...

- What E39 street use brake pads (1) and rotors (1) and suppliers (1) (2) are most often recommended & how to do a complete four wheel brake job DIY (1) (2) (3) including the parking brake drum shoes (1) (2) (3) & exactly what lube/paste to use and not use (1) & where to lube (1) and not to lube (1) what tools (1) (2) and supplies (1) you'll need & what specifications you must know (1) including minimum specs for the brake shoes (1) (2) taking care to measure torque accurately (1) & how to crack friction material edge codes (1) & how far you can go once the brake wear sensor trips (1) (2) (3) (4) & how long do rotors last (1) & how to clear the check brake lining warning the right way (1) (2) and how to hardwire the sensor (1) (2) & how to diagnose brake-related vibration (1) (2) (3) & the truth about rotor "warp" (1) & how to rebuild the calipers (1) & how to measure runout (1) & should you just turn the rotors (1) & how to remove stuck rusted-on brake rotors (1) & how to remove a stuck 6mm brake rotor set screw (1) & how to replace the anti-rattle spring (1) (2) & what about unsightly rust (1) (2) (3) (4) (5) & how to bed (1) (2) & bleed or flush (1) (2) (3) (4) (5) your brakes & what brake & clutch hydraulic fluid to use (1) and how much it will cost if you do not DIY (1) (2) (3)
 

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Discussion Starter · #11 ·
Here's what I do instead of get a helper... I credit Ffej for this technique...

Refill reservoir (not bleeder), pressurize, crack open the bleeder screw and rush into the driver seat and pump the pedal 6-10 times vigorously and quickly. Run back and close bleeder screw, rinse and repeat on each corner. This will force air bubbles out that bleeding alone will not. 25psi isn't enough to cut bubbles loose. It is enough to keep the system pressurized so that when the pedal is returning to it's at-rest position, it will not suck dirty fluid back in at the caliper, or will it take air in. Be sure catch can/hose is submerged at the wheel too.

When working on the front, reduce the pump count as you will go thru the fluid much faster than you will in the rear. Do not let it get too low.
Thank you for this. I'll try this technique :thumbup:
 

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ROLL TIDE!
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If anyone knows about brakes it is JVR, the man USES his brakes in ways we mere mortals only dream about.
 

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Discussion Starter · #13 ·
Here's what I do instead of get a helper... I credit Ffej for this technique...

Refill reservoir (not bleeder), pressurize, crack open the bleeder screw and rush into the driver seat and pump the pedal 6-10 times vigorously and quickly. Run back and close bleeder screw, rinse and repeat on each corner. This will force air bubbles out that bleeding alone will not. 25psi isn't enough to cut bubbles loose. It is enough to keep the system pressurized so that when the pedal is returning to it's at-rest position, it will not suck dirty fluid back in at the caliper, or will it take air in. Be sure catch can/hose is submerged at the wheel too.

When working on the front, reduce the pump count as you will go thru the fluid much faster than you will in the rear. Do not let it get too low.
Jeff, by this you mean I should bring the pressure of the bleeder to 25 psi? and do the pedal thing or do you mean it'll be more than 25 psi when I start pumping the pedal? The Motive instructions do not recommend more that 20 psi. I bleeded at 15psi...may be that's why the brake pedal did not firm up after I was done...
 

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Is it Trackday yet?
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Well, I go to 25 on mine, 20 is ok too. As you pump the pedal the pressure will go down because fluid will be pushed thru the open bleed screw into your catch can.

You want it pressurized so no air is sucked in thru the open bleed screw while you're doing your footwork. The two-dude method requires the screw to be closed before releasing the pedal from the floor, otherwise, air will be sucked back in. Pressurizing the system allows you to work alone.

15psi is nothing really, I think I produce that and more after Burrito Monday. It is definitely not enough to break air bubbles loose in your caliper or lines. If you've read the Zeckhausen bleed method, he recommends tapping the caliper with a rubber mallet to break them loose. I do this step too.

First time you try this, on the passenger rear, pump the pedal only 5 times and go back and close the screw, then check the reservoir level to be sure it didn't go too low. You'll figure out how many pumps you can do safely with practice. It's very important you do not let it get down to the bottom, below the min line, or it will allow air into the ABS manifolds... then you're really gonna have your work cut out for you.

It's better to pump fewer times between topping off the reservoir than going too many.
 

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Discussion Starter · #15 ·
^ we'll do and I do understand the importance of not letting the air in, so I'll be carefull and I'll get a rubber mallet too ( I read about its use for that purpose somewhere). Damn, proper bleeding is not as easy as hooking up a Motive :) Thanks again.
 

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Freude am Fahren
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BMW TIS guidelines state no more than 2bar at most. JFGI to convert bar to psi
 

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Discussion Starter · #17 ·
BMW TIS guidelines state no more than 2bar at most. JFGI to convert bar to psi
2 bars is 29 psi ( if psi means "pounds/square inch). So Jeff is right 25 is fine.
 

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John Voight's BMW
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912 Posts
See the part in red which should apply equally well to the E46 ...

- What E39 street use brake pads (1) and rotors (1) and suppliers (1) (2) are most often recommended & how to do a complete four wheel brake job DIY (1) (2) (3) including the parking brake drum shoes (1) (2) (3) & exactly what lube/paste to use and not use (1) & where to lube (1) and not to lube (1) what tools (1) (2) and supplies (1) you'll need & what specifications you must know (1) including minimum specs for the brake shoes (1) (2) taking care to measure torque accurately (1) & how to crack friction material edge codes (1) & how far you can go once the brake wear sensor trips (1) (2) (3) (4) & how long do rotors last (1) & how to clear the check brake lining warning the right way (1) (2) and how to hardwire the sensor (1) (2) & how to diagnose brake-related vibration (1) (2) (3) & the truth about rotor "warp" (1) & how to rebuild the calipers (1) & how to measure runout (1) & should you just turn the rotors (1) & how to remove stuck rusted-on brake rotors (1) & how to remove a stuck 6mm brake rotor set screw (1) & how to replace the anti-rattle spring (1) (2) & what about unsightly rust (1) (2) (3) (4) (5) & how to bed (1) (2) & bleed or flush (1) (2) (3) (4) (5) your brakes & what brake & clutch hydraulic fluid to use (1) and how much it will cost if you do not DIY (1) (2) (3)
omg how long did it take you to put this post together?
 

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Reading all the different DIYs and comments is making this confusing. I have a few questions if someone can help clarify:

When using the Motive Pressure Bleeder does the reservior need to be drained first? If so, is it completely or just till the minimum line?
So tap brakes with mallet AND do the brake pump technique multiple times even with the Pressure Bleeder?
For the clutch bleed, does the slave cyclinder actually need to be disconnected? And bleed until the new color brake fluid is visible?
 

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John Voight's BMW
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912 Posts
Reading all the different DIYs and comments is making this confusing. I have a few questions if someone can help clarify:

When using the Motive Pressure Bleeder does the reservior need to be drained first? If so, is it completely or just till the minimum line?
So tap brakes with mallet AND do the brake pump technique multiple times even with the Pressure Bleeder?
For the clutch bleed, does the slave cyclinder actually need to be disconnected? And bleed until the new color brake fluid is visible?
i can only speak from my experience. i use the motive bleeder and do not do any brake pumping. i always get a firm pedal. i also don't do any mallet tapping on anything. when i bleed the clutch i usually do it last after all the brakes and i don't disconnect any master or slave cylinders. and yes i always bleed the brakes and clutch until the new fluid is visible.
 
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