Swapped rear GTI PP brakes can’t get good peddle

[DangerDane2008]

I’ve tried gravity bleeding and I’ve tried using a pressure setup. No matter what I do I can’t get good peddle. Soft all the way down. What am I doing wrong?

 

[xXDavidCXx]

The brake system requires very high psi, around 25-29 IIRC, to get good results.

Are you bleeding all four brakes too?

 

[Supermoto]

When I bled my brakes after replacing some parts, I used the adapter from a motive power bleeder.

https://a.co/d/cJRtaRd

I don't use the power bleeder itself because it pumps all the air through the brake fluid causing bubbles and I just don't jam with that. I use this and pressurize the reservoir to around 30-40psi and it worked like a treat. From what I've been told the GTI needs a decently high pressure to properly bleed out the ABS system and lines.

 

[xXDavidCXx]

When I bled my brakes after replacing some parts, I used the adapter from a motive power bleeder.

https://a.co/d/cJRtaRd

I don't use the power bleeder itself because it pumps all the air through the brake fluid causing bubbles and I just don't jam with that. I use this and pressurize the reservoir to around 30-40psi and it worked like a treat. From what I've been told the GTI needs a decently high pressure to properly bleed out the ABS system and lines.

The motive does not pump air through because you fill the pump with brake fluid, and that is what gets pumped through.

If you see bubbles exiting the brake bleeder, that's what you want, that's what brake bleeding is for.

 

[Supermoto]

The motive does not pump air through because you fill the pump with brake fluid, and that is what gets pumped through.

If you see bubbles exiting the brake bleeder, that's what you want, that's what brake bleeding is for.

No I'm aware of that. What I'm saying is the way the motive pump is designed has you fill it up with brake fluid. The pumping action pressurizes the motive bottle by pumping in air, but that air exists out the bottom of the pump and bubbles up through the brake fluid. I didn't like that and I also don't need an extra tool laying around so I just use the adapter. I'm well aware of how these things operate and what brake bleeding is for, but I appreciate the effort.

 

[xXDavidCXx]

Well, I’ve never heard of this issue, and it’s never happened to me so user error or lack of understanding could be the culprit.

Just trying to help.

 

[StorableComa]

I’ve tried gravity bleeding and I’ve tried using a pressure setup. No matter what I do I can’t get good peddle. Soft all the way down. What am I doing wrong?

Probably need to do a post bleed.
https://golfmk7.com/forums/index.php?threads/brake-bleed-question-newb-here.401308/post-7836823

 

[El_bigote_AJ]

No I'm aware of that. What I'm saying is the way the motive pump is designed has you fill it up with brake fluid. The pumping action pressurizes the motive bottle by pumping in air, but that air exists out the bottom of the pump and bubbles up through the brake fluid. I didn't like that and I also don't need an extra tool laying around so I just use the adapter. I'm well aware of how these things operate and what brake bleeding is for, but I appreciate the effort.

When you use the adapter cap and 10” of hose what did you use to pressurize the reservoir to 30 to 40psi? Was it air?

 

[Supermoto]

When you use the adapter cap and 10” of hose what did you use to pressurize the reservoir to 30 to 40psi? Was it air?

Yes it was air but I'm pressurizing the airspace above the fluid, not pumping the air up through the fluid into the airspace above. The motive power bleeder (or at least the one I had) pumped the air out the bottom of the black pump up through the fluid. Similar to how a bong works. I didn't like bubbling humid air up through my brake fluid so I just go the other route. I'm aware many people stand behind the motive power bleeder but I just see it as unnecessary in multiple ways. Just my 2 cents.

 

[donefor]

Motive works without fluid in it, just hook the adapter to the master cylinder and pump the reservoir up to 30 psi, then bleed away.
I considered putting fluid in it when i first got it, but decided i'd rather not deal with the mess. There is nothing to clean up when used dry.

 

[xXDavidCXx]

this thread be like