X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from willowsprings.uwyo.edu ([129.72.10.31] verified) by logan.com (CommuniGate Pro SMTP 5.3.7) with ESMTPS id 4340568 for flyrotary@lancaironline.net; Tue, 08 Jun 2010 15:33:59 -0400 Received-SPF: none receiver=logan.com; client-ip=129.72.10.31; envelope-from=SBoese@uwyo.edu Received: from ponyexpress-ht1.uwyo.edu (ponyexpress-ht1.uwyo.edu [10.84.60.208]) by willowsprings.uwyo.edu (8.14.2/8.14.2) with ESMTP id o58JXLvR026200 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=FAIL) for ; Tue, 8 Jun 2010 13:33:21 -0600 (MDT) (envelope-from SBoese@uwyo.edu) Received: from ponyexpress-mb5.uwyo.edu ([fe80::9813:248c:2d68:a28b]) by ponyexpress-ht1 ([10.84.60.208]) with mapi; Tue, 8 Jun 2010 13:33:20 -0600 From: "Steven W. Boese" To: Rotary motors in aircraft Date: Tue, 8 Jun 2010 13:33:19 -0600 Subject: RE: [FlyRotary] Re: high/low pressure pumps question Thread-Topic: [FlyRotary] Re: high/low pressure pumps question Thread-Index: AcsHL9QHRf6jdgOHRQOeAMrbgv9D8AADrm1c Message-ID: References: In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: multipart/alternative; boundary="_000_E1AA3B1AF41D8049B1E3FBD5E225626004D4FE7C75ponyexpressmb_" MIME-Version: 1.0 --_000_E1AA3B1AF41D8049B1E3FBD5E225626004D4FE7C75ponyexpressmb_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Kelly, When the statement was made that the air would eventually be eliminated thr= ough the vent, I didn't mean to imply that it was necessary to have this ha= ppen. It would be best to avoid drawing the bubbles directly into the fuel= supply line which would only happen if the fuel was returned very close to= the supply inlet. On one wing tank, I have the return entering center of= the root rib about a foot away from the supply inlet. For the other tank,= the return outlet is next to the filler cap which is always above the fuel= level and as far away from the supply inlet as is possible. No difference= in operation of the two tanks has been noticed. A reason given for returning the fuel below the liquid level has been to re= duce foaming. There may be other reasons. I haven't seen much tendency fo= r gasoline to foam under conditions present in my system. Steve Boese RV6A, 1986 13B NA, RD1A, EC2 ________________________________ From: Rotary motors in aircraft [flyrotary@lancaironline.net] On Behalf Of = Kelly Troyer [keltro@att.net] Sent: Tuesday, June 08, 2010 11:26 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: high/low pressure pumps question Guys, Very enlightening and truly food for thought to those of us still in the = construction stage...........I have just one more question to ask............Previous info seemed to indicate that r= eturn fuel should be entering the fuel tank at the bottom or at least close to the bottom.............In ligh= t of Steve's observations would it seem reasonable that air bubbles in the return fuel would be eliminated to = the tank vent faster if the return line was at the top or close to the top of the tank ??................ Kelly Troyer "Dyke Delta"_13B ROTARY Engine "RWS"_RD1C/EC2/EM2 "Mistral"_Backplate/Oil Manifold --_000_E1AA3B1AF41D8049B1E3FBD5E225626004D4FE7C75ponyexpressmb_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Kelly,

When the statement was made that the = air would eventually be eliminated through the vent, I didn't mean to imply= that it was necessary to have this happen. It would be best to avoid= drawing the bubbles directly into the fuel supply line which would only happen if the fuel was returned very close to= the supply inlet. On one wing tank, I have the return ent= ering center of the root rib about a foot away from the supply inlet. = For the other tank, the return outlet is next to the filler cap which is always above the fuel level and as far away from = the supply inlet as is possible. No difference in operation of the tw= o tanks has been noticed.

A reason given for returning the fuel= below the liquid level has been to reduce foaming. There m= ay be other reasons. I haven't seen much tendency for gasoline to foa= m under conditions present in my system.

Stev= e Boese

RV6A, 1986 13B NA, RD1A, EC2&n= bsp;

=

From: Rotary moto= rs in aircraft [flyrotary@lancaironline.net] On Behalf Of Kelly Troyer [kel= tro@att.net]
Sent: Tuesday, June 08, 2010 11:26 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: high/low pressure pumps question

Guys,

Very enlightening and truly food for thought to those of u= s still in the construction stage...........I have just

one more question to ask............Previous info seemed to indicate t= hat return fuel should be entering the

fuel tank at the bottom or at least close to the bottom.............In= light of Steve's observations would it

seem reasonable that air bubbles in the return fuel would be elim= inated to the tank vent faster if the return

line was at the top or close to the top of the tank ??................=

Kelly Troyer
"Dyke Delta"_13B ROTARY Engine
"RWS"_RD1C/EC2/EM2
"Mistral"_Backplate/Oil Manifold

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