X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from wproxy.gmail.com ([64.233.184.199] verified) by logan.com (CommuniGate Pro SMTP 5.0.8) with ESMTP id 971218 for flyrotary@lancaironline.net; Sun, 05 Feb 2006 17:18:31 -0500 Received-SPF: pass receiver=logan.com; client-ip=64.233.184.199; envelope-from=russell.duffy@gmail.com Received: by wproxy.gmail.com with SMTP id 37so1099359wra for ; Sun, 05 Feb 2006 14:17:46 -0800 (PST) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:from:to:subject:date:message-id:mime-version:content-type:x-priority:x-msmail-priority:x-mailer:importance:x-mimeole:in-reply-to; b=Pdga/w3GuN9zCcG3SJ+Em/3uXH2+3goXfVn1n/Uv83GqUc50S+URnmWCxipsvX4k+h0BdlnaVlRO5Enn0a4lV/VOzxHSFtlh+EH62niSl6Ff+D5kuUlH6bFvTMCzcYR5/u3wLI8WHWr/aFfXXRqEj9yatC0F4Ao3e0cooCDmwRc= Received: by 10.54.156.6 with SMTP id d6mr803838wre; Sun, 05 Feb 2006 14:17:45 -0800 (PST) Return-Path: Received: from rd ( [65.6.194.9]) by mx.gmail.com with ESMTP id 15sm12873317wrl.2006.02.05.14.17.45; Sun, 05 Feb 2006 14:17:45 -0800 (PST) From: "Russell Duffy" To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Fuel Check Valves needed?? Date: Sun, 5 Feb 2006 16:17:45 -0600 Message-ID: <005101c62aa1$fdbe82a0$6101a8c0@rd> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0052_01C62A6F.B32412A0" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6626 Importance: Normal X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2670 In-Reply-To: This is a multi-part message in MIME format. ------=_NextPart_000_0052_01C62A6F.B32412A0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit What say ye? Should there be a check valve after each pump? I don't believe a typical EFI pump will need a check valve. There's either one built in, or the pump mechanism just prevents backflow. This has been true for the Walbro pumps I've used, which is what Tracy used to sell. I'm not sure if that's what he still sells though. You can try to blow back through your pump, and verify this for yourself to be sure. Cheers, Rusty (lots of rpm, but no thrust) ------=_NextPart_000_0052_01C62A6F.B32412A0 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Message

What say ye?  Should there be a check valve after = each=20 pump?

I don't = believe a=20 typical EFI pump will need a check valve.  There's either one built = in, or=20 the pump mechanism just prevents backflow.  This has been true for = the=20 Walbro pumps I've used, which is what Tracy used to sell.  I'm not = sure if=20 that's what he still sells though. 
 
You = can try to blow=20 back through your pump, and verify this for yourself to be=20 sure.
 
Cheers,
Rusty = (lots of rpm, but=20 no thrust)



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