---------------------------------------------------------- RV10-List Digest Archive --- Total Messages Posted Fri 09/08/17: 19 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:14 AM - Re: Re: Fuel selector valve (Werner Schneider) 2. 06:41 AM - Van's builders in the news (Kelly McMullen) 3. 06:52 AM - Re: Fuel line testing (rvdave) 4. 07:05 AM - Re: Re: Fuel line testing (Phillip Perry) 5. 07:41 AM - Re: Van's builders in the news (Phil Yoder) 6. 08:04 AM - Re: Re: Fuel selector valve (Rene) 7. 08:23 AM - Re: Van's builders in the news (Bob Leffler) 8. 08:36 AM - Re: Van's builders in the news (Kelly McMullen) 9. 08:44 AM - Re: Fuel line testing (rvdave) 10. 09:12 AM - Re: Re: Fuel line testing (Phillip Perry) 11. 03:25 PM - Re: Fuel line testing (rvdave) 12. 03:56 PM - Re: Re: Fuel line testing (Phillip Perry) 13. 03:59 PM - Re: Van's builders in the news (Ralph E. Capen) 14. 04:19 PM - Re: Fuel line testing (rvdave) 15. 04:54 PM - Re: Re: Fuel line testing (Phillip Perry) 16. 05:02 PM - Re: Fuel line testing (rvdave) 17. 06:11 PM - Re: Re: Fuel line testing (Kelly McMullen) 18. 07:24 PM - Re: Re: Fuel line testing (Phillip Perry) 19. 09:15 PM - Re: Re: Fuel line testing (Kelly McMullen) ________________________________ Message 1 _____________________________________ Time: 03:14:49 AM PST US Subject: Re: RV10-List: Re: Fuel selector valve From: Werner Schneider --- MIME Errors - No Plain-Text Section Found --- A message with no text/plain MIME section was received. The entire body of the message was removed. Please resend the email using Plain Text formatting. HOTMAIL is notorious for only including an HTML section in their client's default configuration. If you're using HOTMAIL, please see your email application's settings and switch to a default mail option that uses "Plain Text". --- MIME Errors No Plain-Text Section Found --- ________________________________ Message 2 _____________________________________ Time: 06:41:52 AM PST US From: Kelly McMullen Subject: RV10-List: Van's builders in the news Always good to see folks I am acquainted with through various forums in the news, in this case for obtaining alternate methods of compliance (AMOC) with regard to the NavWorx AD: "The AMOCs were obtained by three individual aircraft owners. *Bob Leffler * of Columbus, Ohio, requested an AMOC for the Garmin GTN 650 and GTN 750 series of GPS navigators, and has become a spokesman for the group; *Ralph Capen* sought an AMOC for the Garmin GNS 430W and GNS 530W series, and *Phi l Yoder* for the Garmin GNS 480. =9CRalph and I submitted our AMOCs independently before we knew each other,=9D Leffler said. They met th rough the Van=99s Air Force online forum. =9CPhil joined in later bec ause he=99s a friend, and has the 480. =9CI had never heard of an AMOC before,=9D Leffler continued. =9CIt was clearly synergistic once we all knew about each other. But it wasn=99t rocket science.=9D He and Capen simply picked up their phones and called the guy whose name was at the bottom of the AD=99s final rule . Leffler said the FAA was very helpful in guiding the three owners through the AMOC process." Extracted from the weekly AOPA news email. Kelly ________________________________ Message 3 _____________________________________ Time: 06:52:07 AM PST US Subject: RV10-List: Re: Fuel line testing From: "rvdave" ""One thing I'd mention is that me fuel valve is going to leak by in the body between your right and left tanks. When it's flowing fuel and operating near neutral pressures, it will seal up. But when you put pressure (or vacuum on it) it will leak by the seals/o-rings internally. Took me a while to figure that out"". Ok, so I'm pressurizing at the wing root, capped before going into fuel servo, have the afp purge valve outlet plugged and I am showing a leak / won't hold pressure, but can't find any fittings leaking with bubble test. Could my stock fuel valve be leaking ? Even if it was all outlets are capped so should hold pressure? Puzzled -------- Dave Ford RV6 for sale RV10 building Cadillac, MI Read this topic online here: http://forums.matronics.com/viewtopic.php?p=472612#472612 ________________________________ Message 4 _____________________________________ Time: 07:05:38 AM PST US From: Phillip Perry Subject: Re: RV10-List: Re: Fuel line testing Lol. You're right where I was when I tried it too. Head scratching. Are you capped at both tanks? Sent from my iPhone > On Sep 8, 2017, at 8:51 AM, rvdave wrote: > > > ""One thing I'd mention is that me fuel valve is going to leak by in the body between your right and left tanks. When it's flowing fuel and operating near neutral pressures, it will seal up. But when you put pressure (or vacuum on it) it will leak by the seals/o-rings internally. Took me a while to figure that out"". > > Ok, so I'm pressurizing at the wing root, capped before going into fuel servo, have the afp purge valve outlet plugged and I am showing a leak / won't hold pressure, but can't find any fittings leaking with bubble test. Could my stock fuel valve be leaking ? Even if it was all outlets are capped so should hold pressure? Puzzled > > -------- > Dave Ford > RV6 for sale > RV10 building > Cadillac, MI > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=472612#472612 > > > > > > > > > ________________________________ Message 5 _____________________________________ Time: 07:41:42 AM PST US From: Phil Yoder Subject: Re: RV10-List: Van's builders in the news If I can be of any help, please let me know. Phil On Fri, Sep 8, 2017 at 6:48 AM Kelly McMullen wrote: > Always good to see folks I am acquainted with through various forums in > the news, in this case for obtaining alternate methods of compliance (AMO C) > with regard to the NavWorx AD: > "The AMOCs were obtained by three individual aircraft owners. *Bob > Leffler * of Columbus, Ohio, requested an AMOC for the Garmin GTN 650 and > GTN 750 series of GPS navigators, and has become a spokesman for the grou p; *Ralph > Capen* sought an AMOC for the Garmin GNS 430W and GNS 530W series, and *P hil > Yoder* for the Garmin GNS 480. =9CRalph and I submitted our AMOCs > independently before we knew each other,=9D Leffler said. They met through > the Van=99s Air Force online forum. =9CPhil joined in later b ecause he=99s a > friend, and has the 480. > > =9CI had never heard of an AMOC before,=9D Leffler continued. =9CIt was clearly > synergistic once we all knew about each other. But it wasn=99t rock et > science.=9D He and Capen simply picked up their phones and called t he guy > whose name was at the bottom of the AD=99s final rule > . Leffler > said the FAA was very helpful in guiding the three owners through the AMO C > process." > Extracted from the weekly AOPA news email. > Kelly > -- Phil Yoder phil@philyoder.com \__________o-( )-o__________/ www.itsnotthatcomplex.com ________________________________ Message 6 _____________________________________ Time: 08:04:57 AM PST US From: "Rene" Subject: RE: RV10-List: Re: Fuel selector valve Don't know for sure, but I think after a lot of work in phase 1 in 2008 I have the system sealed very well. I have run a tank dry and also un-ported a tank doing slips. In both cases great response from changing tanks or just coming out of the slip. In the case of running the tank dry I also used Aux pump, but with the slip it recovered before I even hit the pump. Vapor lock has been a concern for me because of the heat in the tunnel and does add to my desire to change it if I ever do this again. I have a friend who has asked me to help with his RV-10 Quickbuild........so I have been going back through the list of possible mods again. Rene' 801-721-6080 -----Original Message----- From: owner-rv10-list-server@matronics.com [mailto:owner-rv10-list-server@matronics.com] On Behalf Of Kelly McMullen Sent: Thursday, September 07, 2017 8:38 PM Subject: Re: RV10-List: Re: Fuel selector valve If you have no air/vapor in the system, no leaks, etc. then yes siphon is no big deal. Is that the real world in your airplane if you run one tank dry, or your connections are imperfect? Will your fuel not vaporize when suction is applied to it? At 130 degrees runway temperature? Ever tried to start a siphon with mouth suction? The amount of rise definitely makes a difference. On 9/7/2017 3:08 PM, Bob Turner wrote: > > > rene(at)felker.com wrote: >> 1. If I remember HS physics (70's for me), the rise and drop of the line will not really affect how much suction is needed to pull the fuel except to overcome the friction of the longer line. Don't think it matters either way and I am just saying this because it interest me. I do think limiting the number of fuel connections and length of fuel lines has its positive safety benefits. >> 2. I have mine in stock location. I was kit 322 and did that part of the build in 2006 I think, early builder. I have had no problems with the valve. But if I was doing that part of the build again, I would go with the Andair valve. Having it lower in the tunnel would help with the aft heat duct routing also. I think it is a much nicer valve. >> >> Rene' >> 801-721-6080 >> >> -- > > > 1. You're right; in fact, no suction is needed at all, since the pump/filter are lower than the tank. If you open the line at the filter, gas will just run out. However, the pressure is lower, the higher you go. (If you put the valve up 25 feet (!) the pressure would drop to zero and no fuel would flow, no matter how hard the pump pulled. At the elevated valve, pressure will be a bit lower, providing more opportunity for the fuel to vaporize if conditions are right (or should I say 'wrong'?). > 2. Since about mid-2008 the stock valve is located in a slightly (4") lower location than previously, slightly lessening the pressure drop, but also allowing for more room to get the heater SCAT tubing thru there. > > -------- > Bob Turner > RV-10 QB > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=472591#472591 > > > > > > > > > ________________________________ Message 7 _____________________________________ Time: 08:23:04 AM PST US From: Bob Leffler Subject: Re: RV10-List: Van's builders in the news WW91IG5ldmVyIGtub3cgd2hhdCByaWZ0cmFmZiB5b3UgbWF5IGVuZCBjYW1waW5nIG5leHQgdG8g YXQgT1NILiAg8J+YgA0KDQpUaGVyZSBhcmUgdGhlcmUgbW9yZSBBTU9DcyBwZW5kaW5nIHJlbGVh c2UgZnJvbSB0aGUgRkFBLiAgVW5mb3J0dW5hdGVseSBIYXJ2ZXkgaGFzIGltcGFjdGVkIHRoZSBG dCBXb3J0aCBBQ08gcmVzb3VyY2VzLCBzbyBpdCdzIHRha2luZyBhIGJpdCBsb25nZXIuDQoNClRo ZXJlIHdhcyBhbiBvbWlzc2lvbiBvbiBQaGlsJ3MgNDgwIEFNT0MgZm9yIHRoZSAwMDEyLiAgVGhh dCB3aWxsIGJlIGFkZGVkIHRvIGluY2x1ZGUgdGhlIHVzZSBvZiBhIHNlcmlhbCBjaXJjdWl0IGlu IGFkZGl0aW9uIHRvIHRoZSBhcmluYyBvbmUgb24gdGhlIDAwMTMuDQoNCk9uIFJhbHBoJ3MgYW5k IG1pbmUsIHRoZXkgYXJlIGdvaW5nIHRvIGFkZGluZyB0aGUgZW50aXJlIDR4eC81eHgvNnh4Lzd4 eCBmYW1pbHkgb2YgR2FybWluIGdwcy4NCg0KTm93IHdlIGp1c3QgbmVlZCB0byBjb252aW5jZSBC aWxsIHRvIHJlbGVhc2UgNS4wIHRvIHVzIHNvIHRoYXQgd2UgY2FuIHJlc29sdmUgc29tZSBvZiB0 aGUgb3RoZXIgb3V0c3RhbmRpbmcgYnVncyBpbiB0aGUgc29mdHdhcmUuDQoNCkJUVywgUGhpbCBp cyBhYm91dCB0byBqb2luIHRoZSByYW5rcyBvZiB1cyBSVi0xMCBidWlsZGVycy4gIEhlJ3MgYmVl biBsb29raW5nIGF0IHNvbWUgdXNlZCBwcm9qZWN0cyB0byBidXkuICBJZiB5b3Uga25vdyBhbnks IHBsZWFzZSBsZXQgaGltIGtub3cuDQoNCkdldCBPdXRsb29rIGZvciBpT1M8aHR0cHM6Ly9ha2Eu bXMvbzB1a2VmPg0KX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18NCkZyb206IG93bmVy LXJ2MTAtbGlzdC1zZXJ2ZXJAbWF0cm9uaWNzLmNvbSA8b3duZXItcnYxMC1saXN0LXNlcnZlckBt YXRyb25pY3MuY29tPiBvbiBiZWhhbGYgb2YgS2VsbHkgTWNNdWxsZW4gPGFwaWxvdDJAZ21haWwu Y29tPg0KU2VudDogRnJpZGF5LCBTZXB0ZW1iZXIgOCwgMjAxNyA5OjQwOjIyIEFNDQpUbzogcnYx MC1saXN0QG1hdHJvbmljcy5jb20NClN1YmplY3Q6IFJWMTAtTGlzdDogVmFuJ3MgYnVpbGRlcnMg aW4gdGhlIG5ld3MNCg0KQWx3YXlzIGdvb2QgdG8gc2VlIGZvbGtzIEkgYW0gYWNxdWFpbnRlZCB3 aXRoIHRocm91Z2ggdmFyaW91cyBmb3J1bXMgaW4gdGhlIG5ld3MsIGluIHRoaXMgY2FzZSBmb3Ig b2J0YWluaW5nIGFsdGVybmF0ZSBtZXRob2RzIG9mIGNvbXBsaWFuY2UgKEFNT0MpIHdpdGggcmVn YXJkIHRvIHRoZSBOYXZXb3J4IEFEOg0KIlRoZSBBTU9DcyB3ZXJlIG9idGFpbmVkIGJ5IHRocmVl IGluZGl2aWR1YWwgYWlyY3JhZnQgb3duZXJzLiBCb2IgTGVmZmxlciBvZiBDb2x1bWJ1cywgT2hp bywgcmVxdWVzdGVkIGFuIEFNT0MgZm9yIHRoZSBHYXJtaW4gR1ROIDY1MCBhbmQgR1ROIDc1MCBz ZXJpZXMgb2YgR1BTIG5hdmlnYXRvcnMsIGFuZCBoYXMgYmVjb21lIGEgc3Bva2VzbWFuIGZvciB0 aGUgZ3JvdXA7IFJhbHBoIENhcGVuIHNvdWdodCBhbiBBTU9DIGZvciB0aGUgR2FybWluIEdOUyA0 MzBXIGFuZCBHTlMgNTMwVyBzZXJpZXMsIGFuZCBQaGlsIFlvZGVyIGZvciB0aGUgR2FybWluIEdO UyA0ODAuIOKAnFJhbHBoIGFuZCBJIHN1Ym1pdHRlZCBvdXIgQU1PQ3MgaW5kZXBlbmRlbnRseSBi ZWZvcmUgd2Uga25ldyBlYWNoIG90aGVyLOKAnSBMZWZmbGVyIHNhaWQuIFRoZXkgbWV0IHRocm91 Z2ggdGhlIFZhbuKAmXMgQWlyIEZvcmNlIG9ubGluZSBmb3J1bS4g4oCcUGhpbCBqb2luZWQgaW4g bGF0ZXIgYmVjYXVzZSBoZeKAmXMgYSBmcmllbmQsIGFuZCBoYXMgdGhlIDQ4MC4NCg0K4oCcSSBo YWQgbmV2ZXIgaGVhcmQgb2YgYW4gQU1PQyBiZWZvcmUs4oCdIExlZmZsZXIgY29udGludWVkLiDi gJxJdCB3YXMgY2xlYXJseSBzeW5lcmdpc3RpYyBvbmNlIHdlIGFsbCBrbmV3IGFib3V0IGVhY2gg b3RoZXIuIEJ1dCBpdCB3YXNu4oCZdCByb2NrZXQgc2NpZW5jZS7igJ0gSGUgYW5kIENhcGVuIHNp bXBseSBwaWNrZWQgdXAgdGhlaXIgcGhvbmVzIGFuZCBjYWxsZWQgdGhlIGd1eSB3aG9zZSBuYW1l IHdhcyBhdCB0aGUgYm90dG9tIG9mIHRoZSBBROKAmXMgZmluYWwgcnVsZTxodHRwczovL3d3dy5n cG8uZ292L2Zkc3lzL3BrZy9GUi0yMDE3LTA2LTA2L3BkZi8yMDE3LTExNjI1LnBkZj4uIExlZmZs ZXIgc2FpZCB0aGUgRkFBIHdhcyB2ZXJ5IGhlbHBmdWwgaW4gZ3VpZGluZyB0aGUgdGhyZWUgb3du ZXJzIHRocm91Z2ggdGhlIEFNT0MgcHJvY2Vzcy4iDQoNCkV4dHJhY3RlZCBmcm9tIHRoZSB3ZWVr bHkgQU9QQSBuZXdzIGVtYWlsLg0KS2VsbHkNCg= ________________________________ Message 8 _____________________________________ Time: 08:36:20 AM PST US Subject: Re: RV10-List: Van's builders in the news From: Kelly McMullen I have mentioned to someone else that there is an RV-10 partial build for sale at KCHD (Chandler, AZ). I only have email contact, don't know how responsive seller is, and I know it was not built looking for airshow awards. I will send Phil a PM. You never know what ratty, barely flying homebuilt is going to park next to your shiny, fancy -10 at homebuilt camping. 8^) On 9/8/2017 8:17 AM, Bob Leffler wrote: > You never know what riftraff you may end camping next to at OSH. > > > BTW, Phil is about to join the ranks of us RV-10 builders. He's been > looking at some used projects to buy. If you know any, please let him > know. > > ________________________________ Message 9 _____________________________________ Time: 08:44:01 AM PST US Subject: RV10-List: Re: Fuel line testing From: "rvdave" Yes capped before entering tanks at wing root. I have a tee on right line forward to purge valve. Introducing air at right wing root. AFP pump after fuel valve, capped line at exit of purge valve, capped line at entrance line before servo. Funny thing is sometimes it appears to be a fast leak down and other times a slow leak down. Your explanation of fuel valve makes sense but can't prove it yet. No leak at stem of valve or nut of valve. Maybe afp pump or mech pump leak ? Still looking. -------- Dave Ford RV6 for sale RV10 building Cadillac, MI Read this topic online here: http://forums.matronics.com/viewtopic.php?p=472625#472625 ________________________________ Message 10 ____________________________________ Time: 09:12:33 AM PST US From: Phillip Perry Subject: Re: RV10-List: Re: Fuel line testing I think you're on the right track. Checking me stem on the valve and bypass valve is a good idea. Also checking the two pumps and the body seams on them might be good too. Not sure about the PSI sensor, but it might have something goofy going on there too. I found that it was impossible to test the entire system, but broke it down and had to check each leg from the fuel valve in segments. I could prove the left side was tight. The right side was tight. The forward part was tight (capped at the inlet of the mechanical fuel pump). When you put it all together the results were inconsistent. Using my hand vacuum pump and gauge, I was able to determine that it didn't take much more than 2-3 inches of suction to suck open the o-rings/seals inside the valve. At 5 it was really moving fuel. That valve has isn't really designed to have pressures on it, it's just designed to provide a path from the tank forward. Phil Sent from my iPhone > On Sep 8, 2017, at 10:43 AM, rvdave wrote: > > > Yes capped before entering tanks at wing root. I have a tee on right line forward to purge valve. Introducing air at right wing root. AFP pump after fuel valve, capped line at exit of purge valve, capped line at entrance line before servo. Funny thing is sometimes it appears to be a fast leak down and other times a slow leak down. Your explanation of fuel valve makes sense but can't prove it yet. No leak at stem of valve or nut of valve. Maybe afp pump or mech pump leak ? Still looking. > > -------- > Dave Ford > RV6 for sale > RV10 building > Cadillac, MI > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=472625#472625 > > > > > > > > > ________________________________ Message 11 ____________________________________ Time: 03:25:23 PM PST US Subject: RV10-List: Re: Fuel line testing From: "rvdave" I have confirmed that the leak/pressure drop is isolated to the afp purge valve itself so I'm not sure how tight this is suppose to be internally. Seems like in ico position there should be no flow to spider but maybe it reacts differently to fuel rather than air? -------- Dave Ford RV6 for sale RV10 building Cadillac, MI Read this topic online here: http://forums.matronics.com/viewtopic.php?p=472670#472670 ________________________________ Message 12 ____________________________________ Time: 03:56:11 PM PST US From: Phillip Perry Subject: Re: RV10-List: Re: Fuel line testing How much pressure are you putting on the line? Sent from my iPhone > On Sep 8, 2017, at 5:24 PM, rvdave wrote: > > > I have confirmed that the leak/pressure drop is isolated to the afp purge valve itself so I'm not sure how tight this is suppose to be internally. Seems like in ico position there should be no flow to spider but maybe it reacts differently to fuel rather than air? > > -------- > Dave Ford > RV6 for sale > RV10 building > Cadillac, MI > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=472670#472670 > > > > > > > > > ________________________________ Message 13 ____________________________________ Time: 03:59:55 PM PST US From: "Ralph E. Capen" Subject: Re: RV10-List: Van's builders in the news Thanks for the shout-out. I'm also available to assist in connection settings as well as communicating with the local FSDO...done that as well. I'm fully legal past the Jan and 2020 deadlines. -----Original Message----- From: Kelly McMullen Sent: Sep 8, 2017 9:40 AM Subject: RV10-List: Van's builders in the news Always good to see folks I am acquainted with through various forums in the news, in this case for obtaining alternate methods of compliance (AMOC) with regard to the NavWorx AD:"The AMOCs were obtained by three individual aircraft owners. Bob Leffler of Columbus, Ohio, requested an AMOC for the Garmin GTN 650 and GTN 750 series of GPS navigators, and has become a spokesman for the group; Ralph Capen sought an AMOC for the Garmin GNS 430W and GNS 530W series, and Phil Yoder for the Garmin GNS 480. Ralph and I submitted our AMOCs independently before we knew each other, Leffler said. They met through the Vans Air Force online forum. Phil joined in later because hes a friend, and has the 480. I had never heard of an AMOC before, Leffler continued. It was clearly synergistic once we all knew about each other. But it wasnt rocket science. He and Capen simply picked up their phones and called the guy whose name was at the bottom of the ADs final rule. Leffler said the FAA was very helpful in guiding the three owners through the AMOC process."Extracted from the weekly AOPA news email.Kelly ________________________________ Message 14 ____________________________________ Time: 04:19:04 PM PST US Subject: RV10-List: Re: Fuel line testing From: "rvdave" 50 psi -------- Dave Ford RV6 for sale RV10 building Cadillac, MI Read this topic online here: http://forums.matronics.com/viewtopic.php?p=472675#472675 ________________________________ Message 15 ____________________________________ Time: 04:54:07 PM PST US From: Phillip Perry Subject: Re: RV10-List: Re: Fuel line testing Yeah that's way too much. That valve is basically a hole that rotates around inside a cylinder and is sealed with o-rings. 50 psi will push those o-rings right out of the way. I don't recall what the psi is forward of the servo, but I seem to recall its very low. The spider (iirc) operates with a series of check valves that are normally closed and they only open when the cylinder on the intake stroke sucks them open. Then they close. That way fuel can be kept at the spider but it's sucked into the proper cylinder. I might be over simplifying that, and others can correct me. But that's how I seem to recall it working. So 50 psi on the back side of the spider would just spray fuel down all the lines at the same time. So it pretty sure 50psi is way too high. Try dialing it down to something like 2 lbs (if you can) and see what you get. I suspect you will find that the leak stops once you get down to a lower pressure. If you can't do that, try putting your thumb over one side, sucking a vacuum through it, and plugging it with your tongue to see if it holds. You can generate enough suction to suck open the o-rings with your mouth. But you can prove it seals. Sent from my iPhone > On Sep 8, 2017, at 6:18 PM, rvdave wrote: > > > 50 psi > > -------- > Dave Ford > RV6 for sale > RV10 building > Cadillac, MI > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=472675#472675 > > > > > > > > > ________________________________ Message 16 ____________________________________ Time: 05:02:30 PM PST US Subject: RV10-List: Re: Fuel line testing From: "rvdave" Thanks for the info, that's probably why I saw a variance in the bleed down, I'll try lower pressure and see how that goes tomorrow. -------- Dave Ford RV6 for sale RV10 building Cadillac, MI Read this topic online here: http://forums.matronics.com/viewtopic.php?p=472677#472677 ________________________________ Message 17 ____________________________________ Time: 06:11:06 PM PST US Subject: Re: RV10-List: Re: Fuel line testing From: Kelly McMullen The input to the fuel servo is 15-30 psi. The output to the fuel flow divider is somewhere between 5 and 10 psi. When the fuel pressure drops below 4 psi there is a valve in the flow divider that closes to enable full idle cutoff. The intake valve opening has nothing to do with the delivery of fuel to the injector. Our injectors are continuous flow, and all that varies is the amount of fuel delivered. The fuel pressure the servo delivers to the flow divider determines the rate of fuel delivered to the intake manifold. The injector nozzle atomizes the fuel, which then hopefully vaporizes for uniform delivery into the cylinder. Certainly the purge valve should withstand up to 15 psi of fuel pressure. Air pressure is a different animal. If the purge valve doesn't leak with the engine running, it isn't the problem. You could fasten a paper towel around the valve outlet, then don't purge at shut down. If there are any fuel stains on the paper towel, it leaks. On 9/8/2017 4:52 PM, Phillip Perry wrote: > > Yeah that's way too much. That valve is basically a hole that rotates around inside a cylinder and is sealed with o-rings. 50 psi will push those o-rings right out of the way. > > I don't recall what the psi is forward of the servo, but I seem to recall its very low. The spider (iirc) operates with a series of check valves that are normally closed and they only open when the cylinder on the intake stroke sucks them open. Then they close. That way fuel can be kept at the spider but it's sucked into the proper cylinder. I might be over simplifying that, and others can correct me. But that's how I seem to recall it working. > > So 50 psi on the back side of the spider would just spray fuel down all the lines at the same time. So it pretty sure 50psi is way too high. > > Try dialing it down to something like 2 lbs (if you can) and see what you get. I suspect you will find that the leak stops once you get down to a lower pressure. > > If you can't do that, try putting your thumb over one side, sucking a vacuum through it, and plugging it with your tongue to see if it holds. > > You can generate enough suction to suck open the o-rings with your mouth. But you can prove it seals. > > > > Sent from my iPhone > >> On Sep 8, 2017, at 6:18 PM, rvdave wrote: >> >> >> 50 psi >> >> -------- >> Dave Ford >> RV6 for sale >> RV10 building >> Cadillac, MI >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=472675#472675 >> >> >> >> >> >> >> >> >> > > > > ________________________________ Message 18 ____________________________________ Time: 07:24:22 PM PST US From: Phillip Perry Subject: Re: RV10-List: Re: Fuel line testing Back at the house where I can check the AFP flow divider manual. It doesn't sound like there's much pressure on the spider (or valve) from their description. I scanned for an exact number, but 1.75-3 PSI is the best I could find. Needless to say, I'd check with with a much smaller amount of pressure. Is the engine running or is this still in a new build? If it's a new build, I'd just check what you can check and work on the assumptions that the valves are behaving as designed until they really do exhibit a problem and warrant going down the rabbit hole of diagnosing a leak that may not exist. Phil FLOW DIVIDER 1-7. Metered fuel is delivered from the fuel controller to the flow divider. It's purpose is to divide the metered fuel equally to each injection nozzle at idle regardless of their height between each other. At idle, nozzle back pressure is typically 1-5 inches of gas pressure, if there is a difference in height between the nozzles then idle flow will tend to flow out the lowest nozzles. Metered fuel pressure enters the flow divider through a channel that permits fuel to pass through the I.D. of the flow divider spool valve. At idle the fuel pressure from the fuel controller must build up to overcome the spring force applied to the diaphragm and spool valve. This moves the spool valve upward to allow fuel to pass through the calibrated slots in the bottom of the flow divider bushing. Since the fuel controller meters and delivers a fixed amount of fuel to the flow divider, the spool valve will only open as far as necessary to pass the amount of fuel to the nozzles. Since it takes approximately 1.75-3 PSI pressure to open the spool valve, the fuel will accurately be divided between the nozzles if there is a difference in height between them of 70 inches. At idle the nozzle discharge pressure is negligible, the opening of the spool valve to the slots is very small, and thus the fuel is divided for the individual cylinders at this point by the flow divider. The flow divider also keeps the metered fuel under pressure and shuts off the individual nozzle ports when the fuel controller is placed in "idle cutoff". On Fri, Sep 8, 2017 at 7:20 PM, Kelly McMullen wrote: > > The input to the fuel servo is 15-30 psi. The output to the fuel flow > divider is somewhere between 5 and 10 psi. When the fuel pressure drops > below 4 psi there is a valve in the flow divider that closes to enable full > idle cutoff. The intake valve opening has nothing to do with the delivery > of fuel to the injector. Our injectors are continuous flow, and all that > varies is the amount of fuel delivered. The fuel pressure the servo > delivers to the flow divider determines the rate of fuel delivered to the > intake manifold. The injector nozzle atomizes the fuel, which then > hopefully vaporizes for uniform delivery into the cylinder. > Certainly the purge valve should withstand up to 15 psi of fuel pressure. > Air pressure is a different animal. If the purge valve doesn't leak with > the engine running, it isn't the problem. You could fasten a paper towel > around the valve outlet, then don't purge at shut down. If there are any > fuel stains on the paper towel, it leaks. > > On 9/8/2017 4:52 PM, Phillip Perry wrote: > >> >> Yeah that's way too much. That valve is basically a hole that rotates >> around inside a cylinder and is sealed with o-rings. 50 psi will push >> those o-rings right out of the way. >> >> I don't recall what the psi is forward of the servo, but I seem to recall >> its very low. The spider (iirc) operates with a series of check valves >> that are normally closed and they only open when the cylinder on the intake >> stroke sucks them open. Then they close. That way fuel can be kept at >> the spider but it's sucked into the proper cylinder. I might be over >> simplifying that, and others can correct me. But that's how I seem to >> recall it working. >> >> So 50 psi on the back side of the spider would just spray fuel down all >> the lines at the same time. So it pretty sure 50psi is way too high. >> >> Try dialing it down to something like 2 lbs (if you can) and see what you >> get. I suspect you will find that the leak stops once you get down to a >> lower pressure. >> >> If you can't do that, try putting your thumb over one side, sucking a >> vacuum through it, and plugging it with your tongue to see if it holds. >> >> You can generate enough suction to suck open the o-rings with your >> mouth. But you can prove it seals. >> >> >> >> Sent from my iPhone >> >> On Sep 8, 2017, at 6:18 PM, rvdave wrote: >>> >>> >>> 50 psi >>> >>> -------- >>> Dave Ford >>> RV6 for sale >>> RV10 building >>> Cadillac, MI >>> >>> >>> >>> >>> Read this topic online here: >>> >>> http://forums.matronics.com/viewtopic.php?p=472675#472675 >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >> >> >> > > ________________________________ Message 19 ____________________________________ Time: 09:15:42 PM PST US From: Kelly McMullen Subject: Re: RV10-List: Re: Fuel line testing Phil, The pressures discussed above are for engine idle and idle cutoff. They are significantly higher when you are using substantial power. They are saying the spool valve is likely to close at anything less than 3 psi to achieve idle cutoff. -sent from the I-droid implanted in my forearm On Fri, Sep 8, 2017 at 7:22 PM, Phillip Perry wrote: > Back at the house where I can check the AFP flow divider manual. It > doesn't sound like there's much pressure on the spider (or valve) from > their description. I scanned for an exact number, but 1.75-3 PSI is the > best I could find. > > Needless to say, I'd check with with a much smaller amount of pressure. > > Is the engine running or is this still in a new build? If it's a new > build, I'd just check what you can check and work on the assumptions that > the valves are behaving as designed until they really do exhibit a problem > and warrant going down the rabbit hole of diagnosing a leak that may not > exist. > > Phil > > > FLOW DIVIDER > > 1-7. Metered fuel is delivered from the fuel controller to the flow > divider. It's purpose is to divide the metered fuel equally to each > injection nozzle at idle regardless of their height between each other. At > idle, nozzle back pressure is typically 1-5 inches of gas pressure, if > there is a difference in height between the nozzles then idle flow will > tend to flow out the lowest nozzles. Metered fuel pressure enters the flow > divider through a channel that permits fuel to pass through the I.D. of the > flow divider spool valve. At idle the fuel pressure from the fuel > controller must build up to overcome the spring force applied to the > diaphragm and spool valve. This moves the spool valve upward to allow fuel > to pass through the calibrated slots in the bottom of the flow divider > bushing. Since the fuel controller meters and delivers a fixed amount of > fuel to the flow divider, the spool valve will only open as far as > necessary to pass the amount of fuel to the nozzles. Since it takes > approximately 1.75-3 PSI pressure to open the spool valve, the fuel will > accurately be divided between the nozzles if there is a difference in > height between them of 70 inches. At idle the nozzle discharge pressure is > negligible, the opening of the spool valve to the slots is very small, and > thus the fuel is divided for the individual cylinders at this point by the > flow divider. The flow divider also keeps the metered fuel under pressure > and shuts off the individual nozzle ports when the fuel controller is > placed in "idle cutoff". > > On Fri, Sep 8, 2017 at 7:20 PM, Kelly McMullen > wrote: > >> >> The input to the fuel servo is 15-30 psi. The output to the fuel flow >> divider is somewhere between 5 and 10 psi. When the fuel pressure drops >> below 4 psi there is a valve in the flow divider that closes to enable full >> idle cutoff. The intake valve opening has nothing to do with the delivery >> of fuel to the injector. Our injectors are continuous flow, and all that >> varies is the amount of fuel delivered. The fuel pressure the servo >> delivers to the flow divider determines the rate of fuel delivered to the >> intake manifold. The injector nozzle atomizes the fuel, which then >> hopefully vaporizes for uniform delivery into the cylinder. >> Certainly the purge valve should withstand up to 15 psi of fuel pressure. >> Air pressure is a different animal. If the purge valve doesn't leak with >> the engine running, it isn't the problem. You could fasten a paper towel >> around the valve outlet, then don't purge at shut down. If there are any >> fuel stains on the paper towel, it leaks. >> >> On 9/8/2017 4:52 PM, Phillip Perry wrote: >> >>> >>> Yeah that's way too much. That valve is basically a hole that rotates >>> around inside a cylinder and is sealed with o-rings. 50 psi will push >>> those o-rings right out of the way. >>> >>> I don't recall what the psi is forward of the servo, but I seem to >>> recall its very low. The spider (iirc) operates with a series of check >>> valves that are normally closed and they only open when the cylinder on the >>> intake stroke sucks them open. Then they close. That way fuel can be >>> kept at the spider but it's sucked into the proper cylinder. I might be >>> over simplifying that, and others can correct me. But that's how I seem >>> to recall it working. >>> >>> So 50 psi on the back side of the spider would just spray fuel down all >>> the lines at the same time. So it pretty sure 50psi is way too high. >>> >>> Try dialing it down to something like 2 lbs (if you can) and see what >>> you get. I suspect you will find that the leak stops once you get down >>> to a lower pressure. >>> >>> If you can't do that, try putting your thumb over one side, sucking a >>> vacuum through it, and plugging it with your tongue to see if it holds. >>> >>> You can generate enough suction to suck open the o-rings with your >>> mouth. But you can prove it seals. >>> >>> >>> >>> Sent from my iPhone >>> >>> On Sep 8, 2017, at 6:18 PM, rvdave wrote: >>>> >>>> >>>> 50 psi >>>> >>>> -------- >>>> Dave Ford >>>> RV6 for sale >>>> RV10 building >>>> Cadillac, MI >>>> >>>> >>>> >>>> >>>> Read this topic online here: >>>> >>>> http://forums.matronics.com/viewtopic.php?p=472675#472675 >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>> >>> >>> >>> =================================== >> -List" rel="noreferrer" target="_blank">http://www.matronics.com/Navig >> ator?RV10-List >> =================================== >> FORUMS - >> eferrer" target="_blank">http://forums.matronics.com >> =================================== >> WIKI - >> errer" target="_blank">http://wiki.matronics.com >> =================================== >> b Site - >> -Matt Dralle, List Admin. >> rel="noreferrer" target="_blank">http://www.matronics.com/contribution >> =================================== >> >> >> >> > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rv10-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RV10-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/rv10-list Browse Digests http://www.matronics.com/digest/rv10-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.