I just installed brand new rotors and brand new Pagid Yellow pads on my 991S. I also bled the system with my Motive bleeder (wet) using ATE Gold. I used the traditional bleeding method, right rear first, etc. I've done this on all my cars, including Porsches, for more than a decade. My first time on the 991.

On a test drive I noticed that the pedal was really soft with a lot of pedal travel required. Certainly drivable, but not confidence inspiring. To be honest, some non-enthusiasts might not think much about it. But it's noticeable and softer than before I bled.

Right off the bat I attempted to bed in the pads but due to the limitations of the city and traffic could not go very fast or brake very hard, yet I did a slow and accelerate a dozen times or so 60-20mph give or take.

When things cool down I will do some more bleeding and road test again. But I am confident in my technique and can't see where I went wrong. And I realize I have a couple variables with the new pads in the mix. So I don't know if that's part of it.

Any ideas?

 

I have had the same issue before.
Did you do the inside and outside valves??

I have found the best way is to get a friend to sit in the car, pump the pedal and depressed it all the way down several times while bleeding each corner. Pressure bleeder has and has not worked for me on the 991.

I still get some brake fluid weeping out of the bleeder valve...tried blowing it out when I bleed them last week.

 

I did do both valves on each caliper. I will recruit my wife to pump the brakes during my next bleed. Not like she hasn't done this before!

 

I have just found that way works better for this car, it's strange.
If you tracking the car I highly rec using SRF.

 

I'm willing to give it a try. Thanks. As for SRF, I plan that upgrade eventually, but I have so much ATE on the shelf I feel compelled to use it up. At least with all this bleeding I am wasting cheaper fluid.

If you have any more tips or tricks I am all ears. Thanks!

 

I wish I did.
Been hit and miss for me too.

I just bleed them last week with someone in the car and got a great firm pedal afterwards. We pumped the brake 5 times then fully pressed the pedal down several times at each corner to get all the air out.

They should get a bit better after you bed the pads in too. RS-29s are awesome pads.

 

Be aware that if the brakes are bled using the pump the brakes and hold the pedal down method it is not a good idea to bleed so much fluid out at one time that the pedal drops to the floor. This is because the pedal never travels that far in normal use and the result in the piston enters a portion of the cylinder it has not been in before. If the cylinder walls have any corrosion and they can have corrosion this corrosion can damage the piston or its seals.

 

Great point. Thanks. Yes, I am aware and plan to not pump the pedal down more than halfway or so.

 

Well, I bled another 3/4+ liter through the system (using the pump method) and never saw any air bubbles of any sort. It "might" be a little better, but it's not dramatic. Hmmmph. Not sure what to do next. DE next weekend.

I wonder if the brand new Pagid pads have anything to do with the feel? (I never noticed this with my Cayman) I hate to have to put the OEM pads back on to compare. A 991 brake pad change is a royal PITA.

 

What about doing a basic gravity bleed? I haven't bled my Porsche brakes yet, but I assume they work like all others. Just open the valve enough to get a slow drip. I've always switched between blue and gold fluid to ensure I bled through the old stuff. It takes hours, but my pedal feel has always been rock solid.

 

If you can do it safely try and bed in the pads as they are still 'green', but after this if you're still having a soft pedal take it to the dealer for a flush. You do not want any issues at the track.
Bish

 

The dealer is probably the last place that will take the time to really do it right IMO.

 

Just got back from attempting to do a bed-in procedure as prescribed on the Pagid website. Boy, that is darn near impossible without a deserted highway! They seem to stop well but still more pedal travel than I like so, as I mentioned, not completely confidence inspiring. So after things cool down I will see how it all feels tomorrow. Not feeling too optimistic but we'll see.

 

I have had issues with the Motive bleeder myself and found that I always had to finish with the good old fashioned pump the brakes bleed. I know you probably have done this many times, but are you sure the person pumping the brakes does not let the pedal back up until you've closed the bleeder nut? You can also try banging on the caliper with a rubber mallet while you bleed.

 

Thanks. Yes, I am quite careful with the procedure. My wife has the PUMP...HOLD...RELEASE routine down pat! She's a 25 year seasoned brake bleeder pro! And a good sport!