Flushing brake fluid question
 

Hey all,

I have an 04 RX8 and ordered speedbleeders so that I can flush out the old brake fluid with new fluid. I have a couple questions:

1) I didn't order a speedbleeder for the master cylinder, but I am wondering whether it is even necessary to bleed the MC? As long as I keep the reservoir with fluid, I should not get air into the system? Also, I read late 05s and later models don't even have a MC nipple, so I should be able to do this without bleeding it?

2) I am reading that people buy clear tubing to put over the nipple/speedbleeder and run it to a bottle/can, but can someone identify what size tubing I need before I go to the store?

3) How much brake fluid do I actually need to do this? quart? liter?

4) If I use a turkey baster to get as much old fluid out of the reservoir as possible and then add new fluid on top of it, will the new fluid push out the old fluid or will they mix or could the old fluid rise to the top?

Thanks!

1. No, the MC Bleeder was deleted on later S1 (2005), just bleed the Brakes from the farthest point from MC first (rears) and then fronts.

2. Size of tube?, sorry not sure, I have the SB tube, just take a bleeder to the store and make sure you get a foot or so of the size that fits over the nipple snugly.

3. A Litre is roughly a little more than a Quart, so either will do.

4. Yes, take out as much as you can and then refill, remember to bleed your Clutch Slave if you go too low...Hint to put MC Cap back on on first refill and pump and you may get a little blow back inside MC and out onto windscreen if the cap is not on....Just had this happen to me on my 5 as I went too low with the turkey baster...'generally' old and new fluid will mix, hence use the TB.

5. I just finished installing Speed Bleeders on my MX-5 1 hour ago!.

First thing I do is remove as much of the mc fluid as possible and then refill. You won't get all the fluid out so the remaining fluid mixes and if your old fluid was very bad, you may need to remove and refill the mc fluid a second time before proceeding. I have never had to bleed my clutch because I went too low. Although, one of these days I should bleed my clutch.

After refilling the master I bleed from each corner, start with the furthest corner from the mc and work your way side to side, back to front. Be sure the master doesn't go empty. Top off when done.

2. Plastic tubing is cheap enough that you can buy a couple of feet of several sizes. You can also get a bleed hose kit at auto parts stores that includes adapters for different size bleed valves.

4. Unless you stir things up, the new fluid will sit on top of the old. Then just keep pumping/bleeding until the fluid comes out clean. The fluid in the MC will get flushed out on the first corner that you bleed.

Make sure you check the level in the MC periodically as you bleed.

Ken

If your brake fluid is in need of renewal then why would you not do your Clutch Master and Clutch Slave, it is very easy, oh hang on you guys have your BMC on the left side same as Slave, (a little harder) you should still do it...I also use Speed Bleeder on Slave Cylinder (SB7100 or SS7100).

I agree it should be done periodically however not as often as I bleed my brakes. I track my car and flush one bottle of brake fluid almost every track day. Its cheeper to put in fresh clean fluid then end up in the wall. My brake fluid has never been noticibly dirty so the clutch fluid source has always been clean fluid and the clutch fluid does not obsorb as much heat. However I am sure the fluid in the line between the MC and Slave cylinder has obsorbed some moisture and some contamination.

I have a SS clutch line around somewhere I need to install too. Just too many projects on my list right now.