Take the cap off the brake fluid reservoir, and monitor the fluid level after you have pushed each piston back in. Be ready to use a big-bore drinking straw with your finger over the end like a pipette to remove brake fluid from the reservoir before it overflows...
But this is no big deal. You just loosen the nozzle and let a little fluid come out while you push the piston...makes the effort a good deal easier. Then just tighten the nozzle and that's it. You don't have overflow at the reservoir either. Don't worry about air getting into the lines.
But the reason I started loosening the nozzle with this car is that the talk was that not doing so while pushing in the piston could damage the system. How much truth there is here I don't know, but I always loosen now to be safe, and like I said it makes the job easier.
----- Kill ratio of Palestinian children to Israeli children 5.7-to-1, Israel's favor. Kill ratio of all Palestinians to Israelis: over 3-to-1.
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"Don't worry about American pressure on Israel. We, the Jewish people, control America, and the Americans know it." ---Israeli Prime Minister Ariel Sharon, 2001
But I *do* worry about it, one little slip and it's in there.
Whatever works for you is fine. Quite how pushing brake fluid back up to the master cylinder can damage the system escapes me - perhaps someone can explain? Last weekend, I replaced *well* worn pads on a friend's '85 Alfa Spider without cracking any bleed nipples. It only took two hours and the brake pedal is rock solid.
One little slip and it's in there? How? Loosen nozzle, push piston, fluid is displaced out of the valve, tighten nozzle...how can air get in? But what if it did somehow anyway? It'd be easy to get back out, no big problem. Not trying to start a petty argument understand, I just don't follow...
----- Kill ratio of Palestinian children to Israeli children 5.7-to-1, Israel's favor. Kill ratio of all Palestinians to Israelis: over 3-to-1.
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"Don't worry about American pressure on Israel. We, the Jewish people, control America, and the Americans know it." ---Israeli Prime Minister Ariel Sharon, 2001
Of the two ways to do it, one of them has some possibility of letting an air bubble into the cylinder. The other one doesn't. It's really not worth debating if you're happy with cracking the bleed valves for this purpose.
On Thu, 31 Aug 2006 11:19:23 +0100, "Dave Plowman (News)" waffled on about something:
I've got an MOT test on my E36 at the weekend, mine's an auto too, and I've been doing my best to remember to apply the handbrake for the last few weeks and going round the block with it one click on just to clean the shoes up, I never use it, I just push the shifter into park. Seems silly that they could technically fail the car on a handbrake that is actually less of a mechanical lock that the gearbox park.
Other thing is one of those pump spray kitchen cleaners, etc. Rinse well before use. Just put the intake pipe in the reservoir and pump into a container.
I personally had never thought about openning the bleed nipple, and on the face of it, it seems a good idea, however, personally, I would still push the fluid back to the reservoir, but I would do it one caliper at a time, and then pump the brake up. Whilst doing it, I would also open the reservoir and put an absorbant rag over the top. You could also take some fluid out with a medical syringe, which are quite cheap on EBay, then put it back in afterwards (but again, I would be interfering with the equilibrium of the system, the yin and yang -
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The reasons I would still push the fluid back are:
I dont believe I could damage the system
I do not want to open a closed system and lose fluid which I will probably want to replace
I probably wont have topped the fluid up throughout the duration of the pads life, the reservoir quantity is such that it can accommodate both new and old pads
I like to avoid fluid mess
Saying this, both methods work, and the bottom line is whatever makes you feel most comfortable.
FWIW, I went to the trouble to pull out my Bentley Manual.
page 340-5 (Brakes):
Slowly press piston back into caliper. Use care not to damage piston dust seal. See Fig. 6.
NOTE----
Open caliper bleeder screw when pressing piston back into caliper. Catch expelled fluid in appropriate container. This procedure is highly recommended in the case of cars with ABS.
Open the bleeder screw only when applying force to the piston. Do not allow air to be drawn in through the bleeder screw.
. . .
----- Kill ratio of Palestinian children to Israeli children 5.7-to-1, Israel's favor. Kill ratio of all Palestinians to Israelis: over 3-to-1.
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"Don't worry about American pressure on Israel. We, the Jewish people, control America, and the Americans know it." ---Israeli Prime Minister Ariel Sharon, 2001
Well, no. But it doesn't state on the cover (or anywhere else, that I'm aware of) that it does.
I didn't catch that.
----- Kill ratio of Palestinian children to Israeli children 5.7-to-1, Israel's favor. Kill ratio of all Palestinians to Israelis: over 3-to-1.
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"Don't worry about American pressure on Israel. We, the Jewish people, control America, and the Americans know it." ---Israeli Prime Minister Ariel Sharon, 2001
I know the BMW TIS is not as authoritative as a Bentley manual, but it specifically say to push the caliper pistons back using special BMW tool 34 1 050 and to pay attention to the rising fluid level in the expansion tank.
Uh-oh, special tooooollllllssss. When I first bought my beamer, I called a local dealership with a specific question about oil changing, and the dip on the phone was sure to tell me that I would need a, uh, a special tool...... I'm still not sure what he meant, unless it was the big socket for getting the top off the filter housing with. I just went to NAPA and bought one, nothing special about it; would make a good headknocker though.
BTW, does your BMW TIS tell you about "lifetime" fluids? A lot of the crap from BMW ain't worth the paper it's written on.
----- Kill ratio of Palestinian children to Israeli children 5.7-to-1, Israel's favor. Kill ratio of all Palestinians to Israelis: over 3-to-1.
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"Don't worry about American pressure on Israel. We, the Jewish people, control America, and the Americans know it." ---Israeli Prime Minister Ariel Sharon, 2001
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