03-12-2016, 10:34 AM | #1 |
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DIY brake fluid change
I did a brake fluid change today and took some notes which others may find helpful. I am using a MOTIV pressure bleeder. I had a liter of ATE super blue left which I understand will no longer be available. I usually put that in for summer, then switch back to OEM fluid for winter, so the color change is helpful. Moving forward, I plan to start using ATE amber or Motul, and may or may not alternate with OEM fluid for the offseason. Without the distinct color change, I wanted to make sure I know exactly how much fluid it takes for a full flush. I drained the waste into a large measuring cup.
Here is my method: 1) Remove fluid from the reservoir using a syringe until the level is 1mm above minimum. With a full reservoir to start, this is about 200mL. 2) Fill reservoir back to maximum with new fluid, 200mL 3) Place remaining 800mL of new fluid in pressure bleeder tank, seal and pressurize system. 4) Starting at furthest corner, passenger side rear, bleed until color change is complete. This is the slowest color change because there is inevitably some mixing in the reservoir. The fluid looked pretty good after 200mL was out, but I kept it going until I had 300mL through and the color was very dark blue and did not seem to be changing any more. 300mL seems right to get the new fluid completely flushed into the reservoir, through the master cylinder and through this line. 5) Driver's side rear: Distinct color change after 75mL, went to 125mL to be sure. 6) Passenger side front: Distinct color change at 50mL, went to 100 mL to be sure. 7) Driver's side front: distinct color change at 50mL, went to 100 mL to be sure. So, bare minimum for full flush would be 200(reservoir) + 200 + 75 + 50 + 50 = 575mL. And that to me really is bare minimum. Most products come in a 500mL size (OEM is 375mL) so not enough. I would recommend going with a liter so that you don't have to cut it close. I think that rules out Castrol SRF for me unless the $80 price is for 1 liter!! Motul is $20 for each 500mL. I would probably go with 200(reservoir) + 300 + 125 + 100 + 100 = 825mL which allows for some waste in the bleeder tank and tubing and really assures a complete flush. Couldn't really find this kind of information on volumes anywhere, so thought this would be helpful. When I switch to a clear or amber fluid next time, I will verify these numbers. Last edited by CarJunkie; 03-12-2016 at 08:20 PM.. |
03-12-2016, 12:40 PM | #3 |
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Great info - I've not seen any quantification of volumes anywhere else, so this is fantastic.
The only thing I do differently, which makes the process much more tedious, is that I don't add any fluid to the bleeder at all -- I just use it to pressurize the reservoir. I do this because I want to keep the bleeder clean, rather than have to clean it out and have more toxic chemicals floating around. But, that means that you have to keep an eagle eye on reservoir fluid level to avoid entraining air. This is particularly the case when flushing the clutch fluid -- the intake for the clutch from the brake fluid reservoir is very high in the reservoir (haven't really been able to visually locate it on the reservoir or on schematics) so you have to constantly refill the reservoir to prevent the dreaded bubbling of air from the bleed valve. Don't ask me how I know ... Thanks for posting this info. Bravo! You should consider doing this volume measurement for the clutch fluid as well ... |
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03-12-2016, 12:41 PM | #4 |
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03-12-2016, 12:47 PM | #5 |
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Nice writeup CarJunkie would have been cool if you took some pics!
Here is another thread with some pics... DIY Request - Brake Bleeding, Adding/Replacing Brake Fluid Procedure http://www.1addicts.com/forums/showt...=241217&page=2 Dackel
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03-12-2016, 02:00 PM | #6 |
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I use a 3' clear plastic tube that fits over the bleeder screw and prevents a mess. I have always collected back into the can that the new fluid came in, but today I used a reqular marked 1L measuring cup, basic kitchenware. I keep one in the garage for adding liquid chlorine to the pool, so it won't be used for any cooking.
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03-12-2016, 02:02 PM | #7 | |
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Quote:
Also, this was more about assuring I knew how to get a complete flush in the future. Posting the information was an afterthought. |
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03-18-2016, 08:20 AM | #9 |
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I don't believe that needs any special attention, so I have been told.
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03-18-2016, 09:06 AM | #10 |
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If you do the clutch at the same time I absolutely could not get a vacuum bleeder to pull through the clutch. But it brought back fond memories of me in the drivers seat as a little kid...Dad saying "Pump"...."Hold"...."Pump" But now with my youngest son.
And REMOVE THE STINKING CLUTCH DELAY VALVE if it still is installed!!!
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03-18-2016, 06:00 PM | #11 |
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The clutch won't bleed with pressure at the reservoir either. Needs the pedal pumped. It is still a 1 person job because the pedal does not return itself when the bleed valve is open. So you can open valve, push pedal to floor, close valve, pull pedal back up, repeat about 10 times.
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03-18-2016, 08:53 PM | #12 | |
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Quote:
Last edited by ayao; 03-18-2016 at 10:44 PM.. |
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03-18-2016, 09:46 PM | #13 | |
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07-12-2016, 08:00 AM | #14 |
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Waking up this thread . . .
I installed Stoptech braided lines a few days ago. I bled the system with fresh fluid (Motul RBF600) and got a lot of air from each corner as expected. I kept it running and had perfect fluid with no bubbles for an extra 100 mL at each corner. I drove the car for the first time yesterday. The brake pedal was mush. Braking authority was all there, but pedal travel was obviously more than usual. During the line change, there must have been time for some air from the first few corners to make it all the way back to the master cylinder. While the reservoir is the highpoint, all of the lines themselves have highpoints that are about 6" above the MC, so I am not sure how the air could get over the highpoints and then down to the MC, but it must have. Anyhow, by jacking up the back of the car, I got the master cylinder about half way to level. To get all of the air out of it, it really needs to be level. I bled the driver's side front using the old school one guy method. Open bleeder screw, push brake pedal down and brace it against the driver's seat with a 22" aluminum tee-ball bat, then close bleeder, remove bat, repeat. You may laugh, but it works! I definitely got air out. Pedal feels better after. I have a slanted driveway, so when more brake fluid arrives from HPAuto I will back the car onto my ramps at the steepest part of the driveway and see if I can get the MC perfectly level. It looks to need the chassis at about 20 degrees. My driveway is about 12 degrees, ramps should get the rest. E-brake, tranny in reverse, block the front tires, then I'll do it again, maybe even hit all 4 corners. In case you are wondering, with the car backed onto ramps, tire turned all the way opposite, you can get a tube onto the bleeder and reach to open and close the bleeder screw. Once the tube is on there, it is easy to find it blindly. |
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08-22-2016, 12:25 AM | #15 |
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Marked your numbers on my bleeder can in black permanent marker and used them today when I did a flush. Really helps a lot since you can't get different colored fluid in the US anymore. Thanks so much,
ianc |
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