Brake/Clutch Fluid Change and Bleeding Instructions

[peavynation]

If your mechanic has the Porsche scanner tool, he can cycle the ABS system while bleeding too.

A Rennlister also posted recently of a bad clutch pedal, and it turned out to be a very tiny leak at one of the line junctions, which was allowing air to get in. Could be something similar; it only takes a tiny bit of air to cause a really bad pedal feel. Just food for thought.

Keep us posted.

Yeah, it will be done at the Porsche dealership, so he has all the tools. If a line was leaking wouldn't I see fluid somewhere? I probably need to remove the underbody to make sure. Mine is custom and made from aluminum so many of the gaps of the factory plastic system are gone. But there are no leaks on the inside though.

Yeah, it would leak, but even a super small one could still give a soft pedal. Might be a small loss of fluid pooling somewhere? Hope the dealer fixes it up quick! Report back what it turns out to be.

[heavychevy]

Hey guys, thanks for all the help. Problem solved.

I'm listing all of the symptoms in case someone has a similar issue in the future.

I spent two hours at the dealer on Wednesday night with up to 3-4 mechanics looking at the car because none of them had seen the conditions that my car was displaying. You could hear all the air escaping when the brake was compressed, which lead them to think it was the brake booster, but there was still vacuum when the car was off. There was also little pressure at all going to the rear brakes, the bleeder valve at full open would just barely trickle any fluid out. So we searched for any possible pinched brake lines and found none. Also check all the connections from the brake pedal to the booster for any flaws and there were none. And as I mentioned, if you pressed the brake on idle at all, the motor would start to idle funny. The pedal travel was no resistance for 95% travel and then got rock hard at the bottom.

We decided on shooting for a brake booster which I was hoping this wasn't one of those jobs that you bought parts for that didn't solve the problem and had to keep buying parts. The mechanics said that usually when the brake booster goes bad, the pedal is harder, not soft, so I had serious concerns that this may not be the answer.

I helped with the removal (not at the dealer) of the brake booster and what we found was pretty crazy, the internal rear pin of the booster had somehow escaped the master cylinder shaft that goes into the booster and that whole pin and cylinder that keeps pressure and vacuum in the booster had somehow escaped the brackets that hold it tight,and was stuck outside the internal booster canister allowing all the air to escape. This created a problem with engine since the engine provides the vacuum to the booster. Put on the new brake booster and pedal feel and everything came back instantaneously, brakes work fine, they bled much better, and no engine idle problems.

I meant to take some pics, but we were there all day fixing a front diff leak and rear oil leak and I was just plain too tired.

Again thanks for the help, and were this unlikely event ever to happen to someone in the future hope this shortens your research and saves you time.

[4agdtym]

I'm planning on changing fluid this weekend. Any variations for the '01 Boxster? How about the look or location of the clutch bleeder?

Thanks,

David

[996noob]

hi,

i am bleeding my brakes for the first time. I do not have the luxury of a Motive Bleeder and have to do the manual way of depressing the clutch from an assistant.

Loren mentioned that it is not the best way to do it as air may be introduced as compared to the bleeder, but if I really have to do it, do i have to keep the pedal depressed all the way while releasing the valves? Or do I keep pumping it? Also, do I drain the old fluid till it comes to the MIN level on the reservior before topping up with the new one?

Is there a good way of doing it the manual way?

I am changing my fluid to the super blue now and would be switching it between the gold and blue every 2 years, has anyone experienced the blue dye (ATE) staining the reservior?

Thanks

I'm in Singapore too. Where do you buy ATE Super Blue from?

[magnum]

Hi,

Wonder if there is any torque # for bleed valve?

thx

Mike

[Loren]

Hi,

Wonder if there is any torque # for bleed valve?

thx

Mike

6 - 9 ftlb.

But I usually do just tight enough to not leak.

[judgejon]

2003 C4S... 30k service question

car was in the shop today for service, and I am advised by very good indy that he was only partially able to bleed the brakes. seems he could not loosen all eight bleeder valves on the calipers, only the front outer valves. this means that only the front brakes have been bled. Neither he nor I wanted to risk stripping out the valves during this process. only took about .5 liter to refill the fluid. the brakes feel good and strong. ideas as to what this means and what, if anything, I should do about it would be most welcomed.

[Loren]

2003 C4S... 30k service question

car was in the shop today for service, and I am advised by very good indy that he was only partially able to bleed the brakes. seems he could not loosen all eight bleeder valves on the calipers, only the front outer valves. this means that only the front brakes have been bled. Neither he nor I wanted to risk stripping out the valves during this process. only took about .5 liter to refill the fluid. the brakes feel good and strong. ideas as to what this means and what, if anything, I should do about it would be most welcomed.

Well, the bad news if they are frozen then they are likely rusted and/or corroded.

If it were my car I would carefully spray penetrating oil on those bleeder screws being very careful NOT to get any on the brake disks or pads. Be sure and wipe any excess.

Then give then another try. If you can get them off consider replacing them (930.351.919.00 ventilation valve -- US MSRP $19.02 each).

[4agdtym]

Having bled the brakes and the clutch on my Boxster ... has anyone relocated the clutch bleed valve to a more accessible location? It seems that it wouldn't be too hard to do so with a length of tubing, some kind of brass fitting and some mounting brackets.

David

[judgejon]

2003 C4S... 30k service question

car was in the shop today for service, and I am advised by very good indy that he was only partially able to bleed the brakes. seems he could not loosen all eight bleeder valves on the calipers, only the front outer valves. this means that only the front brakes have been bled. Neither he nor I wanted to risk stripping out the valves during this process. only took about .5 liter to refill the fluid. the brakes feel good and strong. ideas as to what this means and what, if anything, I should do about it would be most welcomed.

Well, the bad news if they are frozen then they are likely rusted and/or corroded.

If it were my car I would carefully spray penetrating oil on those bleeder screws being very careful NOT to get any on the brake disks or pads. Be sure and wipe any excess.

Then give then another try. If you can get them off consider replacing them (930.351.919.00 ventilation valve -- US MSRP $19.02 each).

thanks, Loren. and I appreciate the pm.

[ninsei]

Hi. I have the durametric tool and I wanna bleed the ABS when i bleed the brakes. I'm confused about the exact procedure. While running the ABS, are any bleeder valves open? Do I bleed the whole system like normal first, close all valves, run the ABS and call it done? or ...

[Loren]

Unless the system has been open and there is air in the ABS you likely do not need to bleed it.

For PSM cars run the ABS pump and bleed the right front with the pump running.

Stop the pump. Bleed the rest of the brakes as normal (described in the DIY).

[Red Aero]

Loren,

Sorry, I got confused on one part of the optional clutch bleeding... "Remove the wood. Then, pump the pedal again very slowly by hand for a further 60 seconds. After pressing the pedal down fully about 10 to 15 times, leave the pedal in its normal position." What is the normal position? I chose to end the pumping at the full up position, but did you mean in the down position because that's where the clutch pedal started the procedure?

thanks,

kj

Normal position is with the pedal up.

I bought a new Clutch Master & Slave from Carlsen Porsche last Feb 21. Slave PN 997-116-237-04 & Master PN 996-423-171-06.

Upon installation, i followed this procedure (thrice) in bleeding my new clutch components & to my dismay i still do not have the proper clutch pedal feel. I can only feel pressure start when the clutch pedal is like 2-inches from the floor when depressed. Could i have done something wrong in the process?

[number9ine]

Getting ready to bleed the brakes!

Quick questions from a first timer:

(1) Can I just jack the car up one wheel at a time or do I need to put it on stands? My garage is tight and using 4 stands at the same time is a challenge...

(2) How do the bleeding valves open and how do I tighten them up with the 'bleeding tubes' connected to them? Do I need any tool?

(3) How much fluid should I pump out of the reservoir before I fill it up with new fluid? I am also thinking about using the pump from a liquid soap or something.

(4) What can go wrong and how do I know if the bleeding worked, before I put the car back on the road?

Thanks as usual,

Gustavo

:renntech:

1) you can do a wheel at a time, just be sure to re-pressurize the power bleeder at each wheel. I don't recommend putting the car on one jackstand for stability reasons, especially if you're skipping the bleeder and relying on a helper in the car.

2) As the DIY states, use a 9mm/11mm wrench to open the valves. I place the box end of the wrench onto the bleeder screw, then place the plastic tubing on.

3)I used a plastic sprayer pump from one of those empty spray bottles you can buy at HD or Lowe's. Works a treat. You'll want to evacuate as much fluid as you can. the more new fluid you can place in the reservoir, the less you'll need to top up as you bleed.

4)If you're using clear plastic tubing at the bleed screw, it's apparent when the clean fluid comes through. Make sure you re-tighten all the screws appropriately, and start at the furthest wheel from the brake reservoir (passenger rear), working your way closer. After closing the system and taking a test drive, if your brake pedal doesn't come to full pressure after a pump or two then there's a problem.

Mark

[tanny02996]

Thanks for the great DIY Loren. I made a couple of adjustments to the tools and process:

1. I added a quick connect coupling to the Motive Power Bleeder (picture below) - this certainly made it easier to move things around to get everything in the best position for the job. I recommend this if you don't have the aluminum cap with swivel connection
2. I couldn't find a small enough pump to fit into the reservoir so once I confirmed that they setup was holding pressure I just bled the fluid out through the rear passenger side brake and had a helper monitor the level in the reservoir to ensure I didn't go to low, once it reached the "min" line, I depressurized the power bleeder tank, filled the reservoir and put the rest of the fluid in the power bleeder (I did not add any more fluid to the bleeder during the process, but did need to top off the reservoir once during the process and then again at the end - made for relatively easy clean up). Overall, a very easy process.

Thank you again Loren and good luck to others.

-tanny02

Edited May 28, 2011 by tanny02996

[questforbalance]

I have a 99 Boxster and I flushed my brakes this weekend, but I could not get the clutch bleed valve cap off the slave cylinder. I pulled it, turned, pinched it and did everything I could think of while trying not to break anything, but could not get that darn clutch bleed nipple off.

How do you get that darn thing off?

[Loren]

I have a 99 Boxster and I flushed my brakes this weekend, but I could not get the clutch bleed valve cap off the slave cylinder. I pulled it, turned, pinched it and did everything I could think of while trying not to break anything, but could not get that darn clutch bleed nipple off.

How do you get that darn thing off?

There is a rubber cap and then a bleed screw similar to the brakes bleeders. As old as you car is the rubber cap maybe gone.

[logray]

Cut it off with a razor blade and then replace it. Underneath is metal, so you won't damage anything (as long as you are cutting through the bleeder nozzle cap).

[kaoticsplatter]

I'm having issues with a 1990 Porsche 964, While bleeding the brakes the pedal gets really firm. But when I started the engine to move the car the brake pedal lost all firmness. I redid the brakes and got the firmness back but as soon as I started the car a second time the firmness went away. I'm wondering if it might be the brake booster thats gone bad or if the abs needs to be looked at, as the ABS light is on. Any help or suggestions would be greatly appreciated.

[le bouch]

I've successfully followed these instructions and bled my brakes - thanks!

I want to do the clutch but have questions before I do:

"This is best done when you are bleeding the left (driver's side) rear wheel as the clutch bleed valve is mounted high above the axle on the transmission.

Push the clutch pedal in by hand (very slowly) and use a long piece of wood to hold the pedal down. I wedged the other end (of the wood) between the seat and door frame -- with plenty of soft padding to avoid scratches. A second option is to have a 2nd person sit in the car and keep the clutch pedal FULLY depressed.

Open the clutch bleeder valve until clear, bubble free brake fluid emerges (at least 30 seconds according to Porsche).

DO I CLOSE THE VALVE AT THIS POINT?

Remove the wood.

Then, pump the pedal again very slowly by hand for a further 60 seconds. After pressing the pedal down fully about 10 to 15 times, leave the pedal in its normal position.

DO I OPEN THE VALVE AGAIN HERE?

After allowing a fill time of 90 seconds, check that no more air bubbles appear at the bleeder valve (use a collecting bottle with a  transparent hose). Then close the bleeder valve. Wipe off the area and replace the rubber protective cap over the bleed screw.

You may notice that the clutch pedal does not return... so carefully pull it up (slowly) to it's normal position. Then depress it (slowly) a few (at least 5) times. In a few cycles the feel should return.

[Loren]

You are using a pressure bleeding system (like Motive) so you bleed the clutch with the pedal depressed to clear - then with it in normal position -- then close the valve.. Same rules as brakes wait until it is clear and bubble free.

Then bringing the pedal up very slowly assures that you do not cavitate or otherwise pull air into the system - close the valve as the fluid runs clear and bubble free.

[le bouch]

Loren, thanks so much for the reply. I'm obviously being a bit slow today - could you just confirm:

Pedal held down

Open valve

Clear fluid emerges

Pump pedal as per instructions

Clear fluid emerges (after 90 secs)

Close valve

OR

Pedal held down

Open valve

Clear fluid emerges

CLOSE VALVE

Pump pedal as per instructions

OPEN VALVE

Clear fluid emerges (after 90 secs)

Close valve

Thanks again,

Andy

[Loren]

Pedal held down

Open valve

Clear fluid emerges

Pump pedal as per instructions

Clear fluid emerges (after 90 secs)

Close valve

This is correct following the wait and slowly releasing the pedal.

[le bouch]

Pedal held down

Open valve

Clear fluid emerges

Pump pedal as per instructions

Clear fluid emerges (after 90 secs)

Close valve

This is correct following the wait and slowly releasing the pedal.

Thanks Loren - I couldn't quite get my head around leaving the valve open all that time!

[bar10dah]

Done something stupid tonight...

I replaced my brake fluid in the fall, but didn't do the clutch. I wasn't aware of how to do it back then. But, following the DIY threads here, I decided to tackle the clutch today.

Holy begeezus that's a tight fit! I was able to contort my arm enough to get the rubber hose on the valve and open it up with a wrench. All went well and as I went to refill the reservoir, I accidentally grabbed my can of CHF202 and poured approximately 1/2 to 1 ounce in the reservoir until I finally noticed the can didn't look right.

The CHF202 and ATE Blue are in similar shape/size cans and were sitting right next to each other on my shelf. I grabbed the wrong freakin' can...

So, took a medicine syringe and sucked out as much of the fluid I could from the reservoir. The fill indicator says it was just below MIN so I didn't empty all the fluid out to avoid getting air in the system.

Am I safe? Or is the mixing so bad that I need to do a complete brake fluid flush? If the specific gravity of Pentosin is lighter than the Ate, then I think I've got it all up. If the Pentosin is heavy, then it probably settled in the bottom of the reservoir. :(

What do you guys think?