Johnny DB

I decided to bleed my brakes this weekend using my Motive Power Bleeder. My helper got distracted by the good looking neighbor and let the brake fluid reservoir go completely dry! The air was pushed all the way to the caliper bleed nipple creating and atomized type mist. I had 2 liters of Castrol SRF so thought it would not be a problem and I would simply flush all the air out and push a little extra fluid through to ensure no air was remaining.

Symptoms:
1. Brake pedal is very spongy…my Jetta diesel now has a stiffer pedal. Sigh.
2. If I pump the brake pedal ~5 times it gets stiffer and then goes down some amount, say 30% if I keep firm pressure on the pedal (car is running at stoplight).
3. Maybe it’s all in my head but clutch engagement seems different?

Questions:
1. How do I get my brakes back??
2. Should I drive the car and get the ABS to engage and release potentially trapped air in its circuit?
3. Redo the complete bleed procedure?
4. Is bleeding the master cylinder required?

Thanks in advance.

audipwr1

Likely air in ABS

Need to cycle it while bleeding - durametric should be able to do this

Johnny DB

I have the durametric pro so I think I can cycle the ABS. Will I need to run the ABS cycle for all 8 nipples? Then do a full flush?

Thanks

Evolved Rs

Most likely need to bench bleed the master cylinder if it ran dry.

audipwr1

I've done a full dry refill on an M3 in car with the computer abs control - not sure if possible on GT

For that I never had it go dry

Spyerx

Durametric can cycle the abs. Open bleeder first, start abs cycle, press pedal.

Johnny DB

Firstly, thank you to all for your input.

I'm going to try bleeding again and use the Durametric to cycle the ABS circuit. If this does not work I will try bench bleeding and I will update the thread once I try.

CosmosMpower

When the car is off wouldn't the valve for the ABS be closed and bypassed even if you got air in the system?

Johnny DB

Good question but I have no idea...

ahyiah

i bled my brakes too using the dry motive method and i got the squishy pedal too. i re-bled and decided to just fill the motive with it, it just made things easier and avoids any air getting in.

BartN (TX)

When you're done post a pic of the neighbor.

silviaks

You cannot let the reservoir run dry when doing the dry method. I prefer using the dry method because the hose bursted on me more than once!

You can also integrate a no-leak quick connect to make things easier - https://rennlist.com/forums/993-foru...ethod-use.html

ahyiah

thanks for the quick connect, i was searching for something like that.

as for the dry method, i was continuously disconnecting, refilling the reservoir, and reconnecting the motive to avoid just that issue. i thought i was careful enough to not let it empty out but i must have made a mistake somewhere. thats actually why i recommend just filling the motive tank with fluid, it decreases your risk of making silly mistakes

to the OP, on my first bleed, i did the inside nipple first, then did the outside. i think the actual official process is to do the outside nipple first. i have zero idea if that would actually make a difference, but on my 2nd bleed, i did it the "correct" way (so outside first). i also got extra paranoid and used up almost 3 liters of fluid flushing, i figured better safe than sorry since fluid is cheap, at least when compared to getting into an accident.

KNSBrakes

the only way I have ever had great results with a pressure bleeder is as follows.

Pump up 20-25psi on the bleeder, crack open first nipple, go to brake pedal and SLOWLY pump 1/2 in/out about 6-8 times. Repeat on every bleeder. I was taught this method working on a Porsche Cup team by a long time tech, it is the ONLY way I was able to get a good pedal with a Motive bleeder.

Also, I have a PIWIS and used the bleeding method for the ABS. Coming into T14 at VIR at 135MPH in a Spec Boxster is when I found out that the PIWIS ABS bleed procedure doesn't alwasy work. My method for bleeding ABS now? Find a road with limited grip and nail the brake pedal to trigger ABS, works much better than using the PIWIS.

--Aaron