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Discussion Starter · #1 ·
Going to be replacing a brake hose on the front soon, and want to be bleeding the system afterwards obviously. Can anyone recommend a good brake bleeding kit? I don't have access to any air compressors so whatever kit is recommended really has to be completely standalone and also ideally should enable 1 person to complete the task.

Thanks

Craig
 

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I use the Gunson Eezi-Bleed, which works but has a couple of weak points. You need to connect it to a spare wheel for air pressure, which is a bit of faff. The o-rings degrade, and on my kit the plastic bottle cap cracked (Gunson after-sales support were excellent though, replaced it by mail order immediately).

I'd read great reviews of the Motive product but afaik it's only sold in the US. It has a built-in pressuriser so doesn't require a spare wheel. It might be available by post from US suppliers.
 

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I use a Motive. That said, if I couldn't buy a Motive, I might be inclined to make one, like this:
The DIY $20 brake bleeder

I wrote a DIY on this topic, but the key is to put ~15psi behind the fluid reservoir (i.e. I don't even put fluid in my Motive).
 

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I use a Motive. That said, if I couldn't buy a Motive, I might be inclined to make one, like this:
The DIY $20 brake bleeder

I wrote a DIY on this topic, but the key is to put ~15psi behind the fluid reservoir (i.e. I don't even put fluid in my Motive).
Motive fromBimmerZone.
 

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I would recommend bleeding them the old fashioned way with 2 people as if you are replacing a line you wont get
all the air out, pressure bleeders are ok but having someone press on the brake pedal when you open
the bleed screw is the best.
Absolutely, spot-on advice.

No pressure bleeder is as effective as the two-person method for removing small air bubbles clinging
onto the inside surfaces of the lines. Giving the brake pedal 3 hard stabs and then a hold (bleed port
is then opened), creates the required shock to dislodge these air bubbles.

Regards,
Alan
 

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The two person way is the best, but if you can't find someone to sit around for an afternoon as you run around bleeding lines, most any pump will work, even the little hand pumps, just don't buy the ones at Harbor Freight. When I went last year, they had two at different prices. I bought the higher priced one, and it broke just as I finished bleeding my clutch-Lucky!

I'm planning on going for the more expensive Craftsman bleeder later this year. My friend had the lower priced one, and the gasket broke on the hand pump. The more expensive one looks beefier, and either way, they're backed by Craftsman's lifetime warranty.
 

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I would reccomend bleeding them the old fashioned way with 2 people as if you are replacing a line you wont get all the air out, pressure bleeders are ok but having someone press on the brake pedal when you open the bleed screw is the best.

this is the awesome thing with pressure bleeders. you can use the 2-man method with just 1 person.

ready pressure bleeder
connect bleeder
pressurize bleeder
start at the first wheel, connect your fluid catching device ( a clear silicon tube into an old gatorade bottle with a coat hanger, hanger works great)
open the bleed screw
slowly pump the pedal 3-5 times
close bleeder screw
check pressure bleeder fluid level and pressure
repeat for each wheel.


you won't suck any air back into the system because you always have brake fluid under pressure in the master cylinder fighting atmospheric pressure.

-Pat
 

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I used the motive and good old leg presure

I found that using the movtive pressure bleeder was good when I was flushing the old fluid and running a fair amt of new fluid thru to try and flush the system (I wasn't sure when it was last done so wanted to push as much new fluid thru as possible). If I had done all that the old manual leg pump way I'd probably be hurting pretty bad. Brakes felt fine after the using the pressure bleeder one man method, but went ahead and did the final round of bleeding with two people just to be sure. I can't say I felt much of a difference, but I do like the additional control having two people provides.
 

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This may sound like a strange question, but what are our brakes supposed to feel like when pressing on the pedal? I recently flushed and bled mine, and the brake pedal seems to travel to about equal to the gas pedal before braking begins to be really applied. I really don't think I have any air in the system, and I changed out the master cylinder as well as brake booster so those are brand new. Only other things I can think of is the rotors are too thin, because I have decent pad life remaining.

Or maybe this car just doesn't have "grabby" brakes? What's your experiences?
 

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The two person way is the best, but if you can't find someone to sit around for an afternoon as you run around bleeding lines, most any pump will work, even the little hand pumps, just don't buy the ones at Harbor Freight.
I won't single-out Harbor Freight, but generally with any tools you get what you pay for. Spend a bit more up-front and buy something that will last you the rest of your life. Or the car's life...

Back when I was doing track events almost every weekend, I could bleed my brakes in about 40 minutes. This was, of course, with a pressure bleeder, but having a helper wouldn't take much longer. The helper shouldn't need to sit around all afternoon, maybe just an hour or so. They are also helpful in fetching you a beer while you take off another wheel.

This is why you guys should get married and have kids. Then you've got a wife to help you out. And by the time she's had enough, you get a kid to help. When the kid tires out, get the other kid. I can't tell you how many times I got dragged outside by my dad to help him bleed the brakes.
 

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The stock brakes are spongy regardless of if you have air in the system, there is quite a bit of travel, with a BBK there is alot less travel and a much harder brake pedal feel. If your brake pedal travels about equal to the gas pedal before the brakes begain to apply, that doesnt sound quite right to me. I would bleed them anyway as if they havent been bled for a while, it cant hurt, and also when you changed your master cylinder and brake booster did you bleed the clutch and brakes after just out of intrest?

Yes, they were bled and flushed after the master and booster changeout. All air was expelled at the time, but I believe my problem is possibly because I did not use a GT1 to activate the ABS/DSC modules.

Does anyone think this is a possible source of air in the lines, or would that only make the ABS/DSC not function as well?
 

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I do not think you would have introduced air in to the ABS/DSC modules when changing the master cylinder and booster, and even if you did i dont think that it would cause it to be that more spongy, i would give them another good bleed, i know that sometimes when you bleed at each caliper it can dislodge some more air bubbles in the caliper. When you bleed the system how did you do it?
I started at the right rear, and worked my way around to the front left. I had a friend pump the pedal 5x, and hold pressure on the last pump. I then opened the bleed valve, allowed the fluid to exit, then closed the valve. Then, my friend released pressure and we repeated the process about 4 times per wheel, and then went around again and repeated the process.

I've done this many times before on other cars. Did I miss anything?
 

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One thing to check is how far the pads are sitting off the rotor when the brakes are not applied. In the olden days before ABS it was easy for the piston to stay where it was and not move away from the rotor. I have found myself with the same problem you describe with my old E34. When I inspected I found the piston would move away from the rotor a 1/16th to an 1/8th after service every time the brakes were applied. That is not right, it was like a valve was sticking and the master was pulling the pads way off the rotor. So every time I braked I would first be pushing the pad back to the rotor taking quite a bit of travel to do it.

Any way the short story is if I bedded my brakes in properly, the off gassing from the pad would add just enough vacuum to overcome the tenancy to pull the pad away from the rotor. So I would bed them in drive for a day or two bed them in again and they would be perfect. Can't hurt to try as you should bed in your brakes anyway.
 

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When you first start to bleed the brakes you get your assistant to press the pedal 3-5 times to get the pedal firm and then hold, open the bleed value and close, and then when your friend releases, he just pushes down and holds again, he doesnt then press 3-5 times and holds as this is just to get the pedal firm. I remember dave zeckhausen telling me this when i was bleeding after my BBK, and i had more of a spongy pedal after 2-3 bleeds until i did it the proper way, see this for more info How to Bleed Brakes

I dont think the extra presses really matters, it may be overkill but I like the idea about tapping the caliper with a mallet to try to free up some air bubbles. Also, it may be smart to note that he did the rears first and left the fronts on the ground. Air flows UP. Maybe this helps evacuate more air?

I'm gonna give it another go, maybe from just driving around the past month or so, the bubbles moved to somewhere I can get at them.
 

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So I just got the Motive bleeder for Xmas but haven't used it yet. Basically you guys are saying you still need to utilize a pedal pumper after using the Motive to ensure a proper bleed?
 

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Discussion Starter · #16 ·
I am going to be changing a pipe so I think I will use the old fashioned method with a friend of mine. Question 2, will a decent brand (mobil/castrol) DOT4 brake fluid do or is there a reason to buy specific BMW?
 

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I wouldn't have thought there was any reason to buy fluid from BMW. Just buy whatever they specify, if it's DOT 4, go with that.
 
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