[rbpeirce]

I posted on the Cayman Register, but Lara suggested posting here since your region seems to be more track oriented than most. Somebody has had to run into this.

I don't want to discuss the stupidity that led to this. I just want to find out how to cure it.

This is a 2012 Cayman. After discovering I had air I flushed the system a second time, which did not cure the problem. I'm planning to do it again tomorrow but I'm wondering if I am missing something.

The reservoir is full and I'm not getting any bubbles at any of the bleed valves but still no pedal. Is it possible the air is between the reservoir and the calipers or is it something else?

[Dandelion]

Yeah, it's pretty much assured that the air has to between the reservoir and calipers, if there's no air bubbles coming out when you bleed it.

Do you have any pedal at all?

ed

[Vicegrip]

What system do you have to bleed the brakes? I can walk you through the tricks to get air out of modern systems but typing it will take way too much time. PM me and I will provide contact info. A 5 min conversation of what you have and what has been done will help a lot.

[rbpeirce]

Originally Posted by Varejao17

Do you have any pedal at all?

There is a "catch" about 1-2" down and then it drops pretty close to the floor. I'm not sure what is happening in the first couple of inches or why it then releases. I've not tried to drive the car to see if there are any bakes!

[rbpeirce]

Originally Posted by Vicegrip

What system do you have to bleed the brakes? I can walk you through the tricks to get air out of modern systems but typing it will take way too much time. PM me and I will provide contact info. A 5 min conversation of what you have and what has been done will help a lot.

I am using the Motive Power Bleeder, air only. I drain 125cc from each bleeder valve starting at the right rear inside, left rear, right front and left front. My error was letting the fluid in the reservoir get a little too low when going from the right front to the left! This was compounded by trying to pump the brakes afterwards.

I don't know how to send a PM. Maybe you could send one to me and I can call you tomorrow.

[Jazzbass]

Originally Posted by rbpeirce

I don't know how to send a PM. Maybe you could send one to me and I can call you tomorrow.

See Vicegrip's username above his post? Click that. You'll get a menu popup. Select "Send Private Message" from the menu. The rest should be self explanatory.

[RV4Flyer]

Perhaps up the pressure in the Motive power bleeder to help push out the air. Most people only use 10-15 psi. According to the manual, at least for a 987.1, Porsche says to use 2 Bar which is equivelent to 29 psi. You also may have some air trapped in the ABS. If that is the case perhaps you can find someone with a Durametric tool to help with cycling the system open so that system can get bled. Don't forget about the clutch as well.

[Vicegrip]

Porsche brake flush device not made the same as the Motive. Once you have air in the system upping the pressure most often has the opp outcome for air removal. As the pressure goes up the bubble size goes down and gas density goes up. This makes the bubbles even less likely to be entrained and removed. In my limited experience I have found the vacuum bleeder methods to be better than pressure systems. While under a partial vacuum air bubbles are larger and less dense and more likely to be entrained and removed. The worst method i see is the "dry motive" Way too easy to blow air in and very time consuming to do a proper full true flush of all the old fluid. At best you get a dilution of fluid. Through testing with cars containing old wet fluid and a using a true boil point tester I found that gently flowing old out and stopping when you see the new stuff come out the catch tube only dilutes the old stuff. Pulsing the fluids via 3/4 stroke pedal pumps while flowing it via pressure or vacuum helps as does staged flushing. With old truly compromised fluid I found that a double flush worked well into the 90% or better exchange. Flush, drive some flush again. I also found that the stuff in the reservoir to be the most water contaminated so the last thing I want to do is stuff that into the rest of the system.

General methods I like. YMMV and adjustments to your car's system required.
Old fluid flush. Vacuum the fluid from the reservoir, install fluid refill system, vacuum pull fluid from all four corners with a few brake pedal pulses for each corner. Drive the car some test some fluid from the calipers and repeat as needed until I get to the boil point of the fresh stuff. If you have ABS only cycle it when you know there is no air in the system. Flush, cycle the system then flush some more.

Track car flush that is removing fluid that is not all old and dark. Remove from reservoir and run a couple pints through.

Got air in the master? Got to make the bubbles want to stick to the fluid. Make them bigger via vacuum or bust them up so they flow along in a foamy fluid. Pulse the hell out of the pedal (3/4 stroke don't stroke it to the floor) just before and while flowing fluid to the nearest caliper. This is the trick for older 911 hydro clutch too. Slave has a high point it seems. Pump the clutch, have a buddy flow some fluid via pressure or vacuum and repeat 3 or 4 times.

Best. Get a good vacuum system with an auto refill.
Good. Get a Motive and FFS put the fluid in the tank.
I like the Vacula brand pro system but it is $$$ this one looks similar and not Swiss pricing. Have not used it it just looks like a similar setup. https://www.amazon.com/Mityvac-MV683...+brake+bleeder

[spiffyjiff]

prob a dumb question but if there's air in the clutch part of the line, would that affect the brakes too? i.e. or would air in one part of the system not affect the performance of the "other side"?

[Vicegrip]

Not dumb question at all. The only part they share is the tank