X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Sat, 12 Jan 2013 07:40:38 -0500 Message-ID: X-Original-Return-Path: Received: from imr-ma06.mx.aol.com ([64.12.78.142] verified) by logan.com (CommuniGate Pro SMTP 6.0.1) with ESMTP id 6007549 for lml@lancaironline.net; Fri, 11 Jan 2013 22:44:39 -0500 Received-SPF: pass receiver=logan.com; client-ip=64.12.78.142; envelope-from=rogg@aol.com Received: from mtaout-da01.r1000.mx.aol.com (mtaout-da01.r1000.mx.aol.com [172.29.51.129]) by imr-ma06.mx.aol.com (Outbound Mail Relay) with ESMTP id A64751C0000B8 for ; Fri, 11 Jan 2013 22:44:03 -0500 (EST) Received: from omh-mb01.r1000.mx.aol.com (omh-mb01.r1000.mx.aol.com [172.29.25.150]) by mtaout-da01.r1000.mx.aol.com (MUA/Third Party Client Interface) with ESMTP id 2EF18E0000BC for ; Fri, 11 Jan 2013 22:44:03 -0500 (EST) Received: from mtaout-ma01.r1000.mx.aol.com (mtaout-ma01.r1000.mx.aol.com [172.29.41.1]) by omh-mb01.r1000.mx.aol.com (AOL Outbound Holding Interface) with ESMTP id D97E1E000087 for ; Fri, 11 Jan 2013 22:42:52 -0500 (EST) Received: from [192.168.1.104] (adsl-76-252-221-17.dsl.pltn13.sbcglobal.net [76.252.221.17]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by mtaout-ma01.r1000.mx.aol.com (MUA/Third Party Client Interface) with ESMTPSA id 5D318E0000C0 for ; Fri, 11 Jan 2013 22:42:52 -0500 (EST) Subject: Re: [LML] Fwd: [LML] Re: bleeding brakes References: From: Richard Ogg Content-Type: multipart/alternative; boundary=Apple-Mail-16BE8A76-6A6A-4EDB-B86B-B183E4D2FDE3 X-Mailer: iPad Mail (10A523) In-Reply-To: X-Original-Message-Id: X-Original-Date: Fri, 11 Jan 2013 19:42:51 -0800 X-Original-To: Lancair Mailing List Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (1.0) X-AOL-SCOLL-SCORE: 0:2:408624448:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-global-disposition: G X-AOL-SCOLL-SCORE: 0:2:389572896:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d338150f0dc0321be --Apple-Mail-16BE8A76-6A6A-4EDB-B86B-B183E4D2FDE3 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Sounds like it would work but difficult to do on a one off basis Sent from ME MYSELF and I On Jan 11, 2013, at 4:03 PM, Ralph Love wrote= : >=20 >=20 >=20 > Begin forwarded message: >=20 >> From: "Robert Engholm" >> Date: January 11, 2013, 1:12:40 PM PST >> To: "Ralph Love" >> Subject: Re: [LML] Re: bleeding brakes >>=20 >> I have never heard of pulling a pure vacuum on the master cylinder and re= leasing fluid that will fill all wheel cylinders >> properly. See all the methods listed on wikipedia. >> =20 >> http://en.wikipedia.org/wiki/Brake_bleeding >> =20 >> Robert >> =20 >> ----- Original Message ----- >> From: Ralph Love >> To: Robert Engholm >> Sent: Friday, January 11, 2013 12:12 PM >> Subject: Fwd: [LML] Re: bleeding brakes >>=20 >> Comments from LML >>=20 >>=20 >> Begin forwarded message: >>=20 >>> From: Gary Casey >>> Date: January 10, 2013, 9:01:23 AM PST >>> To: lml@lancaironline.net >>> Subject: [LML] Re: bleeding brakes >>> Reply-To: "Lancair Mailing List" >>> Regarding the bleeding of brakes, the standard method of filling brake s= ystems at automotive factories is to leave all connections tight and pull a v= acuum at the reservoir. Then a measured quantity is added to the reservoir,= the vacuum released and that's it. One problem with our systems is that th= e hoses and lines are larger than they need to be, allowing air bubbles to s= tay in place and not be "dragged along" with the fluid. I think the best ap= proach is to pull a vacuum at the reservoir. It won't "pull debris" from th= e wheel cylinder, as the fluid there stays put. The bubble enlarges and tha= t gives it the impetus to rise to the reservoir. Or, as Robert says, a pres= sure bleed can push the fluid fast enough to drag the air with it. Except I= would probably pressurize the wheel cylinder to at least push the air uphil= l. Either way works, though. >>> Gary Casey >>> =20 >>>=20 >>> =20 >>>> Reverse bleeding pushes all the debris from the wheel cylinder up into t= he master cylinder. This will be trouble in the future.. >>>> The two person method works well but you must not wait long between the= pumping action at the master cylinder as any bubble >>>> in a hose will travel beyond the prior pumping action rendering the ble= ed useless. >>>> The best is the pressure bleed. A small pot is filled with brake fluid a= nd pressurized to 20 psi. The pot is connected to the >>>> master cylinder reservoir. When the bleeder valve is opened at the whee= l cylinder, the fluid is pushed out at a fast rate allowing >>>> all debris and air to escape. This is the de-facto standard in the auto= industry and commercial aircraft. >>>> Robert --Apple-Mail-16BE8A76-6A6A-4EDB-B86B-B183E4D2FDE3 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 7bit
Sounds like it would work but difficult to do on a one off basis

Sent from ME MYSELF and I


On Jan 11, 2013, at 4:03 PM, Ralph Love <ralphlove@stanfordalumni.org> wrote:




Begin forwarded message:

From: "Robert Engholm" <REngholm@interphasic.com>
Date: January 11, 2013, 1:12:40 PM PST
To: "Ralph Love" <ralphlove@stanfordalumni.org>
Subject: Re: [LML] Re: bleeding brakes

I have never heard of pulling a pure vacuum on the master cylinder and releasing fluid that will fill all wheel cylinders
properly. See all the methods listed on wikipedia.
 
 
Robert
 
----- Original Message -----
From: Ralph Love
Sent: Friday, January 11, 2013 12:12 PM
Subject: Fwd: [LML] Re: bleeding brakes

Comments from LML


Begin forwarded message:

From: Gary Casey <casey.gary@yahoo.com>
Date: January 10, 2013, 9:01:23 AM PST
To: lml@lancaironline.net
Subject: [LML] Re: bleeding brakes
Reply-To: "Lancair Mailing List" <lml@lancaironline.net>

Regarding the bleeding of brakes, the standard method of filling brake systems at automotive factories is to leave all connections tight and pull a vacuum at the reservoir.  Then a measured quantity is added to the reservoir, the vacuum released and that's it.  One problem with our systems is that the hoses and lines are larger than they need to be, allowing air bubbles to stay in place and not be "dragged along" with the fluid.  I think the best approach is to pull a vacuum at the reservoir.  It won't "pull debris" from the wheel cylinder, as the fluid there stays put.  The bubble enlarges and that gives it the impetus to rise to the reservoir.  Or, as Robert says, a pressure bleed can push the fluid fast enough to drag the air with it.  Except I would probably pressurize the wheel cylinder to at least push the air uphill.  Either way works, though.
Gary Casey
 

 
Reverse bleeding pushes all the debris from the wheel cylinder up into the master cylinder. This will be trouble in the future..
The two person method works well but you must not wait long between the pumping action at the master cylinder as any bubble
in a hose will travel beyond the prior pumping action rendering the bleed useless.
The best is the pressure bleed. A small pot is filled with brake fluid and pressurized to 20 psi. The pot is connected to the
master cylinder reservoir. When the bleeder valve is opened at the wheel cylinder, the fluid is pushed out at a fast rate allowing
all debris and air to escape. This is the de-facto standard in the auto industry and commercial aircraft.
Robert
--Apple-Mail-16BE8A76-6A6A-4EDB-B86B-B183E4D2FDE3--