X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [199.185.220.220] (HELO priv-edtnes56.telusplanet.net) by logan.com (CommuniGate Pro SMTP 4.3.2) with ESMTP id 968430 for flyrotary@lancaironline.net; Mon, 30 May 2005 21:13:39 -0400 Received-SPF: pass receiver=logan.com; client-ip=199.185.220.220; envelope-from=haywire@telus.net Received: from localhost ([199.185.220.240]) by priv-edtnes56.telusplanet.net (InterMail vM.6.01.04.04 201-2131-118-104-20050224) with ESMTP id <20050531011250.UNTH2009.priv-edtnes56.telusplanet.net@localhost> for ; Mon, 30 May 2005 19:12:50 -0600 Received: from 142.232.8.200 ( [142.232.8.200]) as user a3a27779@192.168.200.1 by webmail.telus.net with HTTP; Mon, 30 May 2005 18:12:50 -0700 Message-ID: <1117501970.429bba120e86c@webmail.telus.net> Date: Mon, 30 May 2005 18:12:50 -0700 From: Todd Bartrim To: Rotary motors in aircraft Subject: will EFI pumps pump air MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit User-Agent: Internet Messaging Program (IMP) 3.1-cvs X-Originating-IP: 142.232.8.200 The only negative I see is not being able to run the tank out without killing the engine. With all the tanks you're talking about having, that's probably not a big deal, but the RV-3 only has two 15 gallon tanks, so using every last gallon is useful If you get any more of those level sensors you could do what I did. I bought the "Fuel Guardian" from Aircraft Extras, but instead of mounting them in a tank as it was designed, I rethreaded them to fit into a 1/4" AL "T" (used proseal on the threads)and I installed each one on the lines from each wing selector valve (one for each side with 3 tanks to select on each side). As soon as air is sensed in this line I get a big flashing light on the panel and I switch tanks. I've found that I can run the engine at cruise power for ~45 secs before the existing fuel is drawn out of the line, giving plenty of time to switch tanks. And in repeated (many times) ground tests, I've also run it untill the engine began to die then switched tanks, turned on Facet pump and recovery is immediate. I've also run it until I knew that most of the line must have air in it, switched pumps to other wing while still producing power, then slected a full tank on the previous wing and switched pumps back again (did I lose anybody?:-),in an attempt to see the effect of a large slug of air going through the injectors (I'm a returnless system, so all air must go through injectors), and the engine continues to run without a hickup. It's my conclusion that the Facet pumps combined with the FI pumps move so much fuel, so fast that the system can handle small amounts of air. Todd Bartrim C-FSTB RV-9endurance 13B Turbo