[boldorider4]

Hi all,

super simple question:
is it ok to use a pneumatic fluid extractor on a BMW F22 break system?

I understand the advantages of using a pressure bleeder (like motiv), but in my friend's shop he doesn't have a second person to press on the break pedal while the pressure bleeder pumps the new fluid through the lines.

On the contrary, the pneumatic fluid extractor method allows him to work independently.

Any thoughts?

[jzeiler4]

I am old school on one man brake bleeding. I use an IV bag (had 5 back surgeries) and a length of silicone tubing. I put the bag on a stand well above the bleed nipple, hook up the hose and open the bleed port.

Then I just pump away at the pedal and there is no way any air can come down the hose to the caliper. I keep the reservoir full and check for a color change in the hose fluid to know when to close the bleed nipple and move to the next one.

Been doing this method for over 25 years and it is simple as it can get.

[Ajowhan]

Originally Posted by boldorider4

Hi all,

super simple question:
is it ok to use a pneumatic fluid extractor on a BMW F22 break system?

I understand the advantages of using a pressure bleeder (like motiv), but in my friend's shop he doesn't have a second person to press on the break pedal while the pressure bleeder pumps the new fluid through the lines.

On the contrary, the pneumatic fluid extractor method allows him to work independently.

Any thoughts?

Im confused, I thought the whole point of a pressure bleeder is to apply pressure so that you don't have to press on the break to apply the pressure???

[jzeiler4]

You can pressurize the reservoir but valving in the MC will not pass fluid until the pedal is pushed a bit to open the port.

[cooolone2]

Originally Posted by jzeiler4

You can pressurize the reservoir but valving in the MC will not pass fluid until the pedal is pushed a bit to open the port.

What?

So... If I leave the zerk fitting open no fluid will come out unless I press the pedal and open a valve?

Anyways...

Pressure bleeders work great... Use a turkey baster or similar to suck out almost all fluid in the reservoir before you start (don't empty it), then fill (to the line), put special cap on, pressurize (not much needed - 10lbs), put the tubing over the caliper zerk, following with a can or bottle and open the bleeder. Furthest from MC first and in succession closer to the MC. Go a little at a time. Flush till clean fluid comes out at each caliper. Stop and keep an eye on the reservoir, keep it full. Stop and fill as needed. Be sure to use pressure release valve as you don't want to mistakenly pop the cover and spray brake guild everywhere when you refill... That's it... 90% of the fluid will be flushed and that's perfect!

Good Luck

[boldorider4]

Thank you cooolone2 and jzeiler4 for your useful advice!
I ended up having it done at a shop where they use a pressure bleeder.
I've also heard debates as to whether the pressure bleeder really eliminates the necessity for a second person to push on the break pedal and get the fluid going. I guess maybe it's only the case for the MC bleeding.

Anyway, I'm surprised that with a pressure bleeder you need to top up the reservoir in the process of bleeding. I thought that with the pressure bleeder you put all necessary fluid in the pressure bleeding tank, so you never have to stop.
Otherwise, I imagine the process of making sure the fluid is enough would be:

1. close the nipple at random while the pressure bleeder doing its job
2. check on the reservoir --> top up is necessary
3. disconnect the bleeder cap from the reservoir
4. top up
5. reattach the cap
6. reopen the nipple
7. carry on with the bleeding