---------------------------------------------------------- LycomingEngines-List Digest Archive --- Total Messages Posted Tue 09/11/12: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:29 AM - Fuel pump cooling (Ralph E. Capen) 2. 06:24 AM - Re: Fuel pump cooling (FLYaDIVE) 3. 06:56 AM - Re: Fuel pump cooling (Ralph E. Capen) 4. 08:09 AM - Re: Fuel pump cooling (FLYaDIVE) ________________________________ Message 1 _____________________________________ Time: 04:29:54 AM PST US From: "Ralph E. Capen" Subject: LycomingEngines-List: Fuel pump cooling For those of you that have installed a cooling shroud on your fuel pump, are you using the entire inch diameter for the flange hole to steal the air? Is it enough / too much? I'm thinking I might open it the full inch and put inserts to reduce it...but then how do I know what's enough..... Ralph ________________________________ Message 2 _____________________________________ Time: 06:24:13 AM PST US Subject: Re: LycomingEngines-List: Fuel pump cooling From: FLYaDIVE Ralph: The 1" size is perfectly acceptable. You can always make it smaller... But, you can't make it bigger - BUT, don't forget, the exhaust area has to be at least TWICE the AREA of the input. Area of a circle = 2Pi*R^2. Barry On Tue, Sep 11, 2012 at 7:27 AM, Ralph E. Capen wrote: > recapen@earthlink.net> > > For those of you that have installed a cooling shroud on your fuel pump, > are you using the entire inch diameter for the flange hole to steal the > air? Is it enough / too much? > > I'm thinking I might open it the full inch and put inserts to reduce > it...but then how do I know what's enough..... > > Ralph > > ________________________________ Message 3 _____________________________________ Time: 06:56:26 AM PST US From: "Ralph E. Capen" Subject: Re: LycomingEngines-List: Fuel pump cooling Thanks Barry, It always comes back to high-school math...... I'm thinking that since this has some official sticker on it, the inlet/outlet areas have been optimized as you have described. Making the inlet smaller will provide continued conformance to the criteria you have listed. Ralph -----Original Message----- From: FLYaDIVE Sent: Sep 11, 2012 9:21 AM Subject: Re: LycomingEngines-List: Fuel pump cooling Ralph: The 1" size is perfectly acceptable. You can always make it smaller... But, you can't make it bigger - BUT, don't forget, the exhaust area has to be at least TWICE the AREA of the input. Area of a circle = 2Pi*R^2. Barry On Tue, Sep 11, 2012 at 7:27 AM, Ralph E. Capen wrote: For those of you that have installed a cooling shroud on your fuel pump, are you using the entire inch diameter for the flange hole to steal the air? Is it enough / too much? I'm thinking I might open it the full inch and put inserts to reduce it...but then how do I know what's enough..... Ralph ========== nes-List" target="_blank">http://www.matronics.com/Navigator?LycomingEngines-List ========== http://forums.matronics.com ========== le, List Admin. ="_blank">http://www.matronics.com/contribution ========== ________________________________ Message 4 _____________________________________ Time: 08:09:27 AM PST US Subject: Re: LycomingEngines-List: Fuel pump cooling From: FLYaDIVE Ralph: Do not become too concerned about vapor lock. Yes, some of the stories you hear are true, but many more are exaggerated. The best things you can do towards its prevention are: 1 - Point the plane into the wind after shutdown. 2 - Open all cowl flaps (if any) 3 - Open the oil door 4 - Turn on and take off with boost pump ON. 5 - Leave boost pump ON until you reach a safe altitude. 6 - The rest is all dependent upon your building practices - The routing of fuel lines and Fire Sleeves, as mentioned. I would NOT reduce the size of the SCAT tube any smaller than 1". Volume of air flow is NOT only dependent upon size of the tube but also the Flow Dynamics of the tube. This means internal turbulence and restrictions [bends, obstructions, roughness, corrugation and input & output restrictions]. And, if you really want to explore the dynamics of this - Look up Open and Closed end Resonance. I know, I know, way more information than needed ;-) Barry On Tue, Sep 11, 2012 at 9:53 AM, Ralph E. Capen wrote: > recapen@earthlink.net> > > Thanks Barry, > > It always comes back to high-school math...... > > I'm thinking that since this has some official sticker on it, the > inlet/outlet areas have been optimized as you have described. > > Making the inlet smaller will provide continued conformance to the > criteria you have listed. > > Ralph > > > -----Original Message----- > From: FLYaDIVE > Sent: Sep 11, 2012 9:21 AM > To: lycomingengines-list@matronics.com > Subject: Re: LycomingEngines-List: Fuel pump cooling > > Ralph: > > > The 1" size is perfectly acceptable. You can always make it smaller... > But, you can't make it bigger - BUT, don't forget, the exhaust area has to > be at least TWICE the AREA of the input. Area of a circle = 2Pi*R^2. > > > Barry > > > On Tue, Sep 11, 2012 at 7:27 AM, Ralph E. Capen > wrote: > > recapen@earthlink.net> > > For those of you that have installed a cooling shroud on your fuel pump, > are you using the entire inch diameter for the flange hole to steal the > air? Is it enough / too much? > > I'm thinking I might open it the full inch and put inserts to reduce > it...but then how do I know what's enough..... > > Ralph > > > ========== > nes-List" target="_blank"> > http://www.matronics.com/Navigator?LycomingEngines-List > ========== > http://forums.matronics.com > ========== > le, List Admin. > ="_blank">http://www.matronics.com/contribution > ========== > > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message lycomingengines-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/LycomingEngines-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/lycomingengines-list Browse Digests http://www.matronics.com/digest/lycomingengines-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.