Return-Path: Received: from border.rfgonline.com ([65.171.123.242] verified) by logan.com (CommuniGate Pro SMTP 4.1.5) with ESMTP-TLS id 2631812 for flyrotary@lancaironline.net; Fri, 10 Oct 2003 14:02:37 -0400 Received: (qmail 22625 invoked from network); 10 Oct 2003 18:06:53 -0000 Received: from unknown (HELO EXCHANGE.rfgonline.com) (192.168.150.101) by 192.168.150.1 with SMTP; 10 Oct 2003 18:06:53 -0000 X-MimeOLE: Produced By Microsoft Exchange V6.0.6249.0 content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Subject: RE: [FlyRotary] Re: EWP - Success at last? Date: Fri, 10 Oct 2003 14:02:36 -0400 Message-ID: <0B27ED95697C4D4CBC82D79E790FE5678B09CA@exchange.rfgonline.com> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [FlyRotary] Re: EWP - Success at last? Thread-Index: AcOPPQornSGPxqJMQpCBoLQOgkDLiQAGwuhQ From: "Robinson, Chad" To: "Rotary motors in aircraft" > Now you've got me interested. I was concerned about the failure mode, = but > having 2 of them. Hmmmm. What does the stock (3rd gen) pump weigh? = What has > to be fabricated to hook them up? What do they cost? I don't know about cost since the engine I'm looking at is a long block = and includes one. But the data I have is that the pulleys and pump weigh = about 10lbs. So even two electric water pumps is an improvement in = weight. > > Of course, what would a check valve look like for a 2"=20 > radiator hose? > Maybe the pump itself will act as a check valve. Maybe, but I'm not sure that's a great way to go. The water flow will = want to follow the path of least resistance, and I'm sure there will be = leakage through the second pump back to the first's inlet - it has to be = less resistance than the radiator(s) and engine block... Given that this = would be near the edge of the functionality to begin with, leakage would = be a Bad Thing (imho). Of course, you could also just run both pumps all the time...