---------------------------------------------------------- LycomingEngines-List Digest Archive --- Total Messages Posted Mon 11/15/21: 5 ---------------------------------------------------------- Today's Message Index: ---------------------- 0. 12:10 PM - Make Sure You're Listed! List of Contributors Coming Soon! (Matt Dralle) 1. 04:51 AM - Fuel Pressure high (=?iso-8859-1?Q?Heinz_St=E4hli?=) 2. 05:11 AM - Fuel Pressure high (=?iso-8859-1?Q?Heinz_St=E4hli?=) 3. 09:47 AM - Re: Fuel Pressure high (Bernie) 4. 11:55 AM - Re: Fuel Pressure high (Kelly McMullen) ________________________________ Message 0 _____________________________________ Time: 12:10:58 PM PST US From: Matt Dralle Subject: LycomingEngines-List: Make Sure You're Listed! List of Contributors Coming Soon! Dear Listers, There's just a few more days left in this year's List Fund Raiser and that means the List of Contributors (LOC) is just around the corner! In December I post a list of everyone that so generously made a Contribution to support the Lists. Its my way of publicly thanking everyone that took a minute to show their appreciation for the Lists. Won't you take minute and assure that your name is on the upcoming LOC? Tell others that you appreciate the Lists. Making a Contribution to support the Lists is fast and easy using your Visa, MasterCard, or Paypal account: https://matronics.com/contribution Or, drop a personal check in the mail to: Matt Dralle / Matronics 581 Jeannie Way Livermore CA 94550 I would like to thank everyone that has so generously made a Contribution thus far during this year's List Fund Raiser! Remember that its YOUR support that keeps these Lists running and improving! Don't forget to include a little comment about how the Lists have helped you! Thank you! Matt Dralle Matronics Email List Administrator ________________________________ Message 1 _____________________________________ Time: 04:51:07 AM PST US From: =?iso-8859-1?Q?Heinz_St=E4hli?= Subject: LycomingEngines-List: Fuel Pressure high Hi all ! I fly a Glastar with a TMX O-360. Fuel pressure comes from an engine drive n pump and is routed to the Dynon fuel pressure sensor via a T-fiiting at th e In-port of the carburetor. Min pressure acc the Lyc manual is 0.5, max is 8.0 PSI. Now on my last flight I got a red Master Warning with FUEL PRESS HIGH aler t from the EMS. Analysis of its data showed normal pressure (around 6.7) during the first part of the cruise, then a sharp rise within 15 sec to 8. 2 and after approx one min a slow decrease again to 6.7, where it stayed for the rest of the flight. The engine ran normally during the event, and fuel flow looked normal too. Now I have no idea what could cause such a pressur e jump, and what to look after before next flight. Any help is greatly appreciated, thank You very much ! _____ Scanned by McAfee and confirmed virus-free. ________________________________ Message 2 _____________________________________ Time: 05:11:51 AM PST US From: =?iso-8859-1?Q?Heinz_St=E4hli?= Subject: LycomingEngines-List: Fuel Pressure high Hi all ! I fly a Glastar with a TMX O-360. Fuel pressure comes from an engine drive n pump and is routed to the Dynon fuel pressure sensor via a T-fiiting at th e In-port of the carburetor. Min pressure acc the Lyc manual is 0.5, max is 8.0 PSI. Now on my last flight I got a red Master Warning with FUEL PRESS HIGH aler t from the EMS. Analysis of its data showed normal pressure (around 6.7) during the first part of the cruise, then a sharp rise within 15 sec to 8. 2 and after approx one min a slow decrease again to 6.7, where it stayed for the rest of the flight. The engine ran normally during the event, and fuel flow looked normal too. Now I have no idea what could cause such a pressur e jump, and what to look after before next flight. Any help is greatly appreciated, thank You very much ! _____ Scanned by McAfee and confirmed virus-free. ________________________________ Message 3 _____________________________________ Time: 09:47:38 AM PST US From: Bernie Subject: Re: LycomingEngines-List: Fuel Pressure high I believe your fuel pump is a constant volume type. It may have a pressure a djustment screw, but does not change pressure without adjustment. So if the p ressure indication changes then a likely cause is a change in the flow down s tream of the pump. An open line would show a drop in pressure. While a pinch ed line would show an increase. A temporary partial obstruction would show w hat you saw. If the obstruction was before the pump the pressure would drop t hen increase as it passed. If vanes, gears or diaphragm, depending upon the s tyle of pump are wearing out the pressure would drop and not return to norma l. B Winston Sent from my iPhone > On Nov 15, 2021, at 3:14 AM, Heinz St=C3=A4hli wrot e: > > =EF=BB > Hi all ! > I fly a Glastar with a TMX O-360. Fuel pressure comes from an engine drive n pump and is routed to the Dynon fuel pressure sensor via a T-fiiting at th e In-port of the carburetor. Min pressure acc the Lyc manual is 0.5, max is 8 .0 PSI. > Now on my last flight I got a red Master Warning with FUEL PRESS HIGH aler t from the EMS. Analysis of its data showed normal pressure (around 6.7) dur ing the first part of the cruise, then a sharp rise within 15 sec to 8.2 and after approx one min a slow decrease again to 6.7, where it stayed for the r est of the flight. The engine ran normally during the event, and fuel flow l ooked normal too. Now I have no idea what could cause such a pressure jump, a nd what to look after before next flight. > Any help is greatly appreciated, thank You very much ! > > > Scanned by McAfee and confirmed virus-free. > ________________________________ Message 4 _____________________________________ Time: 11:55:34 AM PST US Subject: Re: LycomingEngines-List: Fuel Pressure high From: Kelly McMullen Most carbureted Lycomings have a mechanical diaphragm pump, which is non-adjustable. With an old mechanical fuel pressure gauge you would never have noticed the blip in pressure, and it is not significant. The carburetor float is what controls the flow, and if it sticks just a little, the pressure may rise a bit before the needle valve opens. If you were telling us that the pressure was say 12 or 15, then that would be a concern, but less than a whole digit above the Lycoming spec is not something to worry about as long as it isn't enough to force the needle valve open and flood the carburetor bowl. Kelly A&P/IA On 11/15/2021 10:46 AM, Bernie wrote: > I believe your fuel pump is a constant volume type. It may have a > pressure adjustment screw, but does not change pressure without > adjustment. So if the pressure indication changes then a likely cause is > a change in the flow down stream of the pump. An open line would show a > drop in pressure. While a pinched line would show an increase. A > temporary partial obstruction would show what you saw. If the > obstruction was before the pump the pressure would drop then increase as > it passed. If vanes, gears or diaphragm, depending upon the style of > pump are wearing out the pressure would drop and not return to normal. > > B Winston > > Sent from my iPhone > >> On Nov 15, 2021, at 3:14 AM, Heinz Sthli wrote: >> >> >> >> Hi all ! >> >> I fly a Glastar with a TMX O-360. Fuel pressure comes from an engine >> driven pump and is routed to the Dynon fuel pressure sensor via a >> T-fiiting at the In-port of the carburetor. Min pressure acc the Lyc >> manual is 0.5, max is 8.0 PSI. >> >> Now on my last flight I got a red Master Warning with FUEL PRESS HIGH >> alert from the EMS. Analysis of its data showed normal pressure >> (around 6.7) during the first part of the cruise, then a sharp rise >> within 15 sec to 8.2 and after approx one min a slow decrease again to >> 6.7, where it stayed for the rest of the flight. The engine ran >> normally during the event, and fuel flow looked normal too. Now I have >> no idea what could cause such a pressure jump, and what to look after >> before next flight. >> >> Any help is greatly appreciated, thank You very much ! >> >> ------------------------------------------------------------------------ >> >> >> >> >> >> Scanned by McAfee >> >> and confirmed virus-free. >> ------------------------------------------------------------------------------------- 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.