Anyone doing brake bleeding with the "Gravity Method"?

[Hanakuso]

http://www.s2ki.com/s2000/topic/9938...ravity-method/

I noticed this today and two things stuck out to me. They suggest bleeding in the complete opposite order I have been doing, which is farthest to closest. Second of all, they are not pumping the brakes, just letting gravity do the work.

Anyone can confirm this gives the best pedal feel and overall least amount of brake fluid wasted?

[western_seraph]

Originally Posted by Hanakuso

http://www.s2ki.com/s2000/topic/9938...ravity-method/

I noticed this today and two things stuck out to me. They suggest bleeding in the complete opposite order I have been doing, which is farthest to closest. Second of all, they are not pumping the brakes, just letting gravity do the work.

Anyone can confirm this gives the best pedal feel and overall least amount of brake fluid wasted?

Are asking this as confirmation for just changing fluid? Or are you changing parts?

I've always been told to bleed the brakes furthest away from the master cylinder. Do you know what vehicle that is--Some vehicles have their system's routed strange and the RR is not always the furthest in the system. Maybe it is a vehicle specific guide?

If you are just bleeding brakes for the sake of getting new fluid in I think the gravity bleed is fine--If you are bleeding because you opened the system I would say pumping is required to force out the air. I think without that you run the risk of trapped air.

I read this off of StopTech today also--not promoting them as brake gods but still seems to be good information.

1. Under normal operating conditions, and without brake system modifications, typical OEM braking systems have been designed to NOT require bleeding for the life of the vehicle unless the system is opened for repair or replacement. If you're just driving around town or on the highway to work, there is really no need to bleed! There are a few European vehicles which do recommend replacement on a semi-regular basis for other reasons though, so be sure to check in your owner's manual or at your service center for your particular application.
--I don't know if I agree with "dont require bleeding" I probably still would get some fluid out after a pad change.

Also found this
Sequence
1. Begin at the corner furthest from the driver and proceed in order toward the driver. (Right rear, left rear, right front, left front.) While the actual sequence is not critical to the bleed performance it is easy to remember the sequence as the farthest to the closest. This will also allow the system to be bled in such a way as to minimize the amount of potential cross-contamination between the new and old fluid.

Err anyway--hope this helps answer your question. As far as losing fluid gravity bleed will be less than pumping, but as long as the air is out there shouldn't be a difference in pedal feel.

[OrbitalEllipses]

If this has a Subaru ABS system the front corner is linked to the opposite rear corner so the order doesn't really follow the furthest away rule.

[Hanakuso]

Originally Posted by western_seraph

Are asking this as confirmation for just changing fluid? Or are you changing parts?

I've always been told to bleed the brakes furthest away from the master cylinder. Do you know what vehicle that is--Some vehicles have their system's routed strange and the RR is not always the furthest in the system. Maybe it is a vehicle specific guide?

If you are just bleeding brakes for the sake of getting new fluid in I think the gravity bleed is fine--If you are bleeding because you opened the system I would say pumping is required to force out the air. I think without that you run the risk of trapped air.

I read this off of StopTech today also--not promoting them as brake gods but still seems to be good information.

1. Under normal operating conditions, and without brake system modifications, typical OEM braking systems have been designed to NOT require bleeding for the life of the vehicle unless the system is opened for repair or replacement. If you're just driving around town or on the highway to work, there is really no need to bleed! There are a few European vehicles which do recommend replacement on a semi-regular basis for other reasons though, so be sure to check in your owner's manual or at your service center for your particular application.
--I don't know if I agree with "dont require bleeding" I probably still would get some fluid out after a pad change.

Also found this
Sequence
1. Begin at the corner furthest from the driver and proceed in order toward the driver. (Right rear, left rear, right front, left front.) While the actual sequence is not critical to the bleed performance it is easy to remember the sequence as the farthest to the closest. This will also allow the system to be bled in such a way as to minimize the amount of potential cross-contamination between the new and old fluid.

Err anyway--hope this helps answer your question. As far as losing fluid gravity bleed will be less than pumping, but as long as the air is out there shouldn't be a difference in pedal feel.

Thanks for the reply. The car in that DIY is a S2000 and iirc, it's the same procedure as our cars. At least that's what I did when I had an S2K

[xwd]

Originally Posted by OrbitalEllipses

If this has a Subaru ABS system the front corner is linked to the opposite rear corner so the order doesn't really follow the furthest away rule.

With the fancy EBD stuff I don't think they tie them together like that anymore. I know with the newer WRX it doesn't really apply.

The pump is on the drivers side in this car so you would do passenger rear, driver rear, passenger front, and then driver front. It is different from most other Subarus.

[OrbitalEllipses]

Originally Posted by dwx

With the fancy EBD stuff I don't think they tie them together like that anymore. I know with the newer WRX it doesn't really apply.

The pump is on the drivers side in this car so you would do passenger rear, driver rear, passenger front, and then driver front. It is different from most other Subarus.

ORLY? What year did the WRX get EBD? I have tons of their factory manuals I can check out.

[rice_classic]

I don't agree with the notion that cars are designed such that the brake fluid never needs to be changed for the duration of the vehicle's life, system being opened or not. It's not just moisture that affects this fluid (hygroscopic) but heat.

One of the most common causes of master and slave cylinder failure is... old brake fluid. What's ironic is that we're discussing a link from the S2k boards and the S2k is a perfect example of a car that needs it's brake fluid changed regularly (and by that I mean 50k miles). The AP1 MC didn't actually go bad but the seals in the cylinder would stop sealing when the fluid was old. You would push on the pedal and it would gradually go to the floor but your fluid level would be unchanged.

Many AP1 owners, including myself, can attest to the fact that changing the fluid makes the system work as good as new again without throwing new parts at the car. Fresh fluid gave me another 25k miles (including track time) of solid pedal up to the time I sold the car.

So yeah, I just want to dispel the idea that it's ok to never change your fluid even if the system was never opened.

P.S. bled the brakes on my G/F's 60k old Matrix (system had never been opened) and it made a world of difference.


PP.S. I have bled brakes on a dozen cars and over several hundred times (cuz race car) and I've never gravity bled a car because I usually have help and I'm usually in a hurry but since I have to bleed the brakes regularly on the track toy, I'll give this shot and see how it turns out. Recently I've had incredible success with Speed bleeders. Like gravity bleeding, it allows me to bleed my brakes unassisted but quickly.

[grodenglaive]

The gravity method is very slow. If you change pads a lot, the Motive power bleeder is awesome.
re. StopTech site: I can't imagine not bleeding the brakes after changing pads, that is crazy.

[OrbitalEllipses]

Originally Posted by grodenglaive

The gravity method is very slow. If you change pads a lot, the Motive power bleeder is awesome.
re. StopTech site: I can't imagine not bleeding the brakes after changing pads, that is crazy.

Seconded. Motive positive pressure bleeder is amazing. Capillary action is cool too, but slllloooowwww.

[King Tut]

I'm old fashioned. I go with PR, DR, PF, DF and I use a buddy to pump the pedal. It works 100% of the time every time.

[Don Ivey]

Since our cars, and most new ones, have ABS, are there any special considerations to bleeding the system? I think so, but am not certain.

[IShouldStudy]

Originally Posted by rice_classic

PP.S. I have bled brakes on a dozen cars and over several hundred times (cuz race car) and I've never gravity bled a car because I usually have help and I'm usually in a hurry but since I have to bleed the brakes regularly on the track toy, I'll give this shot and see how it turns out. Recently I've had incredible success with Speed bleeders. Like gravity bleeding, it allows me to bleed my brakes unassisted but quickly.

Speed Bleeders FTW. I recently swapped some speed bleeders in and I will never go back. It made things sooo much easier and I could do it on my own.