---------------------------------------------------------- RV-List Digest Archive --- Total Messages Posted Fri 04/03/09: 14 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:56 AM - Fuel tank/burn questions (ACTIVE NZ - Andrew) 2. 06:06 AM - Re: Fuel tank/burn questions (linn) 3. 06:36 AM - Re: Fuel tank/burn questions (Ralph E. Capen) 4. 06:47 AM - Re: Fuel tank/burn questions (Kevin Horton) 5. 07:00 AM - Re: Fuel tank/burn questions (John Bright) 6. 07:43 AM - Re: Fuel tank/burn questions (Mike Robertson) 7. 01:10 PM - Re: Fuel tank/burn questions (Doug Gray) 8. 01:26 PM - Re: Fuel tank/burn questions (Doug Gray) 9. 01:36 PM - Wire splicing technique (Brian Meyette) 10. 02:00 PM - Re: Wire splicing technique (Michael) 11. 02:59 PM - Re: Wire splicing technique (linn) 12. 03:40 PM - Re: Fuel tank/burn questions (Denis Walsh) 13. 03:42 PM - Clarification on fuel tank issue (ACTIVE NZ - Andrew) 14. 07:48 PM - Re: Clarification on fuel tank issue (Jerry Springer) ________________________________ Message 1 _____________________________________ Time: 12:56:32 AM PST US Subject: RV-List: Fuel tank/burn questions From: "ACTIVE NZ - Andrew" Guys, thanks for all the kind responses re fuel caps. It's all sorted. I have some questions which may sound nuts, but which are better asked here than figured out in the air: 1. Has anyone heard of (early) RV-4 tanks of less than 16 gallons capacity? I ran a tank dry today, by mistake, switched over and landed...and when I refuelled, it only took 12.5 gallons. I've got aerobatic baffles, so it takes a while for the fuel to settle in, but I took my time, and 12.5 it was. I then flew on that tank for exactly an hour (2 x 30 mins) and it ran dry AGAIN, which leads me to ask... 2. Is a fuel burn of 16 gallons an hour, WOT, 5000 feet, and leaned ROP reasonable? I was definitely leaned out, albeit conservatively. (Don't have the instrumentation to support LOP running). Sounds crazy to me. Anyone care to tell me what reasonable burns in an 0-360 at altitude, FP, might be? 3. Anything y'all can think of that might reduce the effective volume of a fuel tank? (A leak, I thought....but can't see one - and that doesn't explain the fact that the tank took 12.5 gallons after having been conclusively established as empty, and unseable fuel drained.) 4. OK, now it gets really weird. Anyone ever hear of fuel caps being "sucked" out of the wing, in flight? This happened to me y/day, and again (other wing) 2 days prior. I am aware it sounds bizarre. The RV is just coming off long term sitting around, cos I mainly fly my beloved Harmon Rocket, and I wonder if it's possible that caps could get old, and not "spread" when the lever is snapped flush with the top of the wing. All comments from those more experienced in RVs than me would be welcomed. Me and my RV are just getting to know each other again, after a long time of being unfaithful to her, in the Rocket :) Cheers Andrew ________________________________________________________________________ ________________________________________________________________________ ____________________________________________________________ -----Original Message----- From: owner-rv-list-server@matronics.com [mailto:owner-rv-list-server@matronics.com] On Behalf Of Sam Buchanan Sent: Friday, April 03, 2009 3:01 AM Subject: Re: RV-List: Anyone got a couple of RV fuel caps for sale? ACTIVE NZ - Andrew wrote: > Don't need to be new, can replace the 'O' rings....they're for my > RV-4, but I think most RV caps will fit, yeah? Will pay anything reasonable... > > Feel free to email me off-list lostpianoplayer@hotmail.com > > Thank you > > Andrew Fairfax > http://www.vansaircraft.com/cgi-bin/catalog.cgi?ident=1238679519-14-12&b rowse=am&product=fuel-cap Sam Buchanan ________________________________ Message 2 _____________________________________ Time: 06:06:15 AM PST US From: linn Subject: Re: RV-List: Fuel tank/burn questions Andrew, I'm going to answer even though I'm not an experienced RVer just yet. I am just now coming off a fuel related incident in my Pitts with an O-360 in it. I don't believe you can eat up 16 gal of gas in an hour. I get somewhere between 10 and 11 and hour when I'm WOT doing aerobatics. However things you said may point to your possible problem: If you can suck the caps out, then you can suck fuel out too. I'd replace the O-rings and/or adjust the cap so the caps are really tight ..... to the point where it's hard to open. But what do I know??? Linn ACTIVE NZ - Andrew wrote: > > Guys, thanks for all the kind responses re fuel caps. It's all sorted. > > I have some questions which may sound nuts, but which are better asked > here than figured out in the air: > > 1. Has anyone heard of (early) RV-4 tanks of less than 16 gallons > capacity? I ran a tank dry today, by mistake, switched over and > landed...and when I refuelled, it only took 12.5 gallons. I've got > aerobatic baffles, so it takes a while for the fuel to settle in, but I > took my time, and 12.5 it was. I then flew on that tank for exactly an > hour (2 x 30 mins) and it ran dry AGAIN, which leads me to ask... > > 2. Is a fuel burn of 16 gallons an hour, WOT, 5000 feet, and leaned ROP > reasonable? I was definitely leaned out, albeit conservatively. (Don't > have the instrumentation to support LOP running). Sounds crazy to me. > Anyone care to tell me what reasonable burns in an 0-360 at altitude, > FP, might be? > > 3. Anything y'all can think of that might reduce the effective volume of > a fuel tank? (A leak, I thought....but can't see one - and that doesn't > explain the fact that the tank took 12.5 gallons after having been > conclusively established as empty, and unseable fuel drained.) > > 4. OK, now it gets really weird. Anyone ever hear of fuel caps being > "sucked" out of the wing, in flight? This happened to me y/day, and > again (other wing) 2 days prior. I am aware it sounds bizarre. The RV is > just coming off long term sitting around, cos I mainly fly my beloved > Harmon Rocket, and I wonder if it's possible that caps could get old, > and not "spread" when the lever is snapped flush with the top of the > wing. > > All comments from those more experienced in RVs than me would be > welcomed. Me and my RV are just getting to know each other again, after > a long time of being unfaithful to her, in the Rocket :) > > Cheers > > Andrew > ________________________________ Message 3 _____________________________________ Time: 06:36:00 AM PST US From: "Ralph E. Capen" Subject: Re: RV-List: Fuel tank/burn questions I've not heard of smaller fuel tanks - I thought the -4 and the -6 had similar configurations....so much for what I know... I'm breaking in a new IO360B1F6 (180hp) in my 6A with 19 gal tanks and I see 16 gph fuel flows on my engine monitor - I'm running 25.5 squared for the break-in period. I haven't done much leaning at all as I have been doing most of my flying at 3000' and below. The total fill up matches what the engine monitor says. Ralph RV6A N822AR @ N06 8.3 hrs -----Original Message----- >From: ACTIVE NZ - Andrew >Sent: Apr 3, 2009 3:57 AM >To: rv-list@matronics.com >Subject: RV-List: Fuel tank/burn questions > > >Guys, thanks for all the kind responses re fuel caps. It's all sorted. > >I have some questions which may sound nuts, but which are better asked >here than figured out in the air: > >1. Has anyone heard of (early) RV-4 tanks of less than 16 gallons >capacity? I ran a tank dry today, by mistake, switched over and >landed...and when I refuelled, it only took 12.5 gallons. I've got >aerobatic baffles, so it takes a while for the fuel to settle in, but I >took my time, and 12.5 it was. I then flew on that tank for exactly an >hour (2 x 30 mins) and it ran dry AGAIN, which leads me to ask... > >2. Is a fuel burn of 16 gallons an hour, WOT, 5000 feet, and leaned ROP >reasonable? I was definitely leaned out, albeit conservatively. (Don't >have the instrumentation to support LOP running). Sounds crazy to me. >Anyone care to tell me what reasonable burns in an 0-360 at altitude, >FP, might be? > >3. Anything y'all can think of that might reduce the effective volume of >a fuel tank? (A leak, I thought....but can't see one - and that doesn't >explain the fact that the tank took 12.5 gallons after having been >conclusively established as empty, and unseable fuel drained.) > >4. OK, now it gets really weird. Anyone ever hear of fuel caps being >"sucked" out of the wing, in flight? This happened to me y/day, and >again (other wing) 2 days prior. I am aware it sounds bizarre. The RV is >just coming off long term sitting around, cos I mainly fly my beloved >Harmon Rocket, and I wonder if it's possible that caps could get old, >and not "spread" when the lever is snapped flush with the top of the >wing. > >All comments from those more experienced in RVs than me would be >welcomed. Me and my RV are just getting to know each other again, after >a long time of being unfaithful to her, in the Rocket :) > >Cheers > >Andrew > > >________________________________________________________________________ >________________________________________________________________________ >____________________________________________________________ > > >-----Original Message----- >From: owner-rv-list-server@matronics.com >[mailto:owner-rv-list-server@matronics.com] On Behalf Of Sam Buchanan >Sent: Friday, April 03, 2009 3:01 AM >To: rv-list@matronics.com >Subject: Re: RV-List: Anyone got a couple of RV fuel caps for sale? > > >ACTIVE NZ - Andrew wrote: >> Don't need to be new, can replace the 'O' rings....they're for my >> RV-4, but I think most RV caps will fit, yeah? Will pay anything >reasonable... >> >> Feel free to email me off-list lostpianoplayer@hotmail.com >> >> Thank you >> >> Andrew Fairfax >> > > >http://www.vansaircraft.com/cgi-bin/catalog.cgi?ident=1238679519-14-12&b >rowse=am&product=fuel-cap > >Sam Buchanan > > ________________________________ Message 4 _____________________________________ Time: 06:47:58 AM PST US From: Kevin Horton Subject: Re: RV-List: Fuel tank/burn questions On 3 Apr 2009, at 03:57, ACTIVE NZ - Andrew wrote: > > > > Guys, thanks for all the kind responses re fuel caps. It's all sorted. > > I have some questions which may sound nuts, but which are better asked > here than figured out in the air: > > 1. Has anyone heard of (early) RV-4 tanks of less than 16 gallons > capacity? I ran a tank dry today, by mistake, switched over and > landed...and when I refuelled, it only took 12.5 gallons. I've got > aerobatic baffles, so it takes a while for the fuel to settle in, > but I > took my time, and 12.5 it was. I then flew on that tank for exactly an > hour (2 x 30 mins) and it ran dry AGAIN, which leads me to ask... > > 2. Is a fuel burn of 16 gallons an hour, WOT, 5000 feet, and leaned > ROP > reasonable? I was definitely leaned out, albeit conservatively. (Don't > have the instrumentation to support LOP running). Sounds crazy to me. > Anyone care to tell me what reasonable burns in an 0-360 at altitude, > FP, might be? > > 3. Anything y'all can think of that might reduce the effective > volume of > a fuel tank? (A leak, I thought....but can't see one - and that > doesn't > explain the fact that the tank took 12.5 gallons after having been > conclusively established as empty, and unseable fuel drained.) > > 4. OK, now it gets really weird. Anyone ever hear of fuel caps being > "sucked" out of the wing, in flight? This happened to me y/day, and > again (other wing) 2 days prior. I am aware it sounds bizarre. The > RV is > just coming off long term sitting around, cos I mainly fly my beloved > Harmon Rocket, and I wonder if it's possible that caps could get old, > and not "spread" when the lever is snapped flush with the top of the > wing. > > All comments from those more experienced in RVs than me would be > welcomed. Me and my RV are just getting to know each other again, > after > a long time of being unfaithful to her, in the Rocket :) Andrew, Assuming the fuel tanks were built according to the plans, the tank capacity should be pretty close to 16 USG. But, there are possible fuel pickup issues that could cause the fuel pickup to suck air wile there is still a lot of fuel left in the tank. Possible fuel pickup issues are: 1. inverted fuel pickup hung up inside tank, such that it its end is no longer at the lowest point, 2. inverted fuel pickup unscrewed at the elbow inside the forward inboard end of the tank, 3. normal fuel pickup rotated so that its end is well above the bottom of the tank, or 4. normal fuel pickup tube broken off. See http://www.vansaircraft.com/pdf/sb06-2-23.pdf In all the above cases, you would be able to drain several gallons from the tank drain after a fuel starvation event. One other possible cause is a fuel vent blockage that hinders the air from entering the tank to replace the fuel that is being sucked out. Ensure the fuel vents are completely clear. If you can drain only a minimal amount of fuel from the drain after a fuel starvation event, and an unusually low quantity is required to fill the tank up, maybe there is a large quantity of solid matter in the tank. It would be wise to remove the inspection cover on the inboard end of the tank to do an inspection. Also inspect all fuel filters for contamination. Good luck, -- Kevin Horton (Grounded) RV-8 (Flight Test Phase) Ottawa, Canada http://www.kilohotel.com/rv8 ________________________________ Message 5 _____________________________________ Time: 07:00:15 AM PST US From: John Bright Subject: Re: RV-List: Fuel tank/burn questions What does it mean to suck the caps out of the wing in flight? do not archive Thanks, John Bright o:757-864-2305 h:757-874-0861 c:757-812-1909 ----- Original Message ---- From: ACTIVE NZ - Andrew Sent: Friday, April 3, 2009 3:57:23 AM Subject: RV-List: Fuel tank/burn questions Guys, thanks for all the kind responses re fuel caps. It's all sorted. I have some questions which may sound nuts, but which are better asked here than figured out in the air: 1. Has anyone heard of (early) RV-4 tanks of less than 16 gallons capacity? I ran a tank dry today, by mistake, switched over and landed...and when I refuelled, it only took 12.5 gallons. I've got aerobatic baffles, so it takes a while for the fuel to settle in, but I took my time, and 12.5 it was. I then flew on that tank for exactly an hour (2 x 30 mins) and it ran dry AGAIN, which leads me to ask... 2. Is a fuel burn of 16 gallons an hour, WOT, 5000 feet, and leaned ROP reasonable? I was definitely leaned out, albeit conservatively. (Don't have the instrumentation to support LOP running). Sounds crazy to me. Anyone care to tell me what reasonable burns in an 0-360 at altitude, FP, might be? 3. Anything y'all can think of that might reduce the effective volume of a fuel tank? (A leak, I thought....but can't see one - and that doesn't explain the fact that the tank took 12.5 gallons after having been conclusively established as empty, and unseable fuel drained.) 4. OK, now it gets really weird. Anyone ever hear of fuel caps being "sucked" out of the wing, in flight? This happened to me y/day, and again (other wing) 2 days prior. I am aware it sounds bizarre. The RV is just coming off long term sitting around, cos I mainly fly my beloved Harmon Rocket, and I wonder if it's possible that caps could get old, and not "spread" when the lever is snapped flush with the top of the wing. All comments from those more experienced in RVs than me would be welcomed. Me and my RV are just getting to know each other again, after a long time of being unfaithful to her, in the Rocket :) Cheers Andrew ________________________________________________________________________ ________________________________________________________________________ ____________________________________________________________ -----Original Message----- From: owner-rv-list-server@matronics.com [mailto:owner-rv-list-server@matronics.com] On Behalf Of Sam Buchanan Sent: Friday, April 03, 2009 3:01 AM Subject: Re: RV-List: Anyone got a couple of RV fuel caps for sale? ACTIVE NZ - Andrew wrote: > Don't need to be new, can replace the 'O' rings....they're for my > RV-4, but I think most RV caps will fit, yeah? Will pay anything reasonable... > > Feel free to email me off-list lostpianoplayer@hotmail.com > > Thank you > > Andrew Fairfax > http://www.vansaircraft.com/cgi-bin/catalog.cgi?ident=1238679519-14-12&b rowse=am&product=fuel-cap Sam Buchanan ________________________________ Message 6 _____________________________________ Time: 07:43:52 AM PST US From: Mike Robertson Subject: RE: RV-List: Fuel tank/burn questions Some of the questions have already been answered but I still would like to throw my two cents in. The fuel caps are kept in place by the expansion of the large 'O' ring. Th at 'O' ring will get hard over time and not expand properly. With the low pressure over the top of the wing in flight=2C the fuel cap and fuel can de finitely be sucked right out of the fuel tank (been there=2C done that once already). O-360 f normal fuel flow for 5000=2C properly leaned=2C should be somewhere in the vicinity of 8.5 - 9.2 gallons. Obviously=2C leaning te chniques will have quite a bit of influence on this. Also=2C whether or no t you have any electronic ignition installed will have a bearing. With ele ctronic ignition the fuel flow is somewhat lower. As to the capacity of the tank=2C I totally agree with Kevin Horton. You r eally need to pull the in-board inspection plate and take a look. Mike Robertson Das Fed > Subject: RV-List: Fuel tank/burn questions > Date: Fri=2C 3 Apr 2009 20:57:23 +1300 > From: andrew@nzactive.com > To: rv-list@matronics.com > > > Guys=2C thanks for all the kind responses re fuel caps. It's all sorted. > > I have some questions which may sound nuts=2C but which are better asked > here than figured out in the air: > > 1. Has anyone heard of (early) RV-4 tanks of less than 16 gallons > capacity? I ran a tank dry today=2C by mistake=2C switched over and > landed...and when I refuelled=2C it only took 12.5 gallons. I've got > aerobatic baffles=2C so it takes a while for the fuel to settle in=2C but I > took my time=2C and 12.5 it was. I then flew on that tank for exactly an > hour (2 x 30 mins) and it ran dry AGAIN=2C which leads me to ask... > > 2. Is a fuel burn of 16 gallons an hour=2C WOT=2C 5000 feet=2C and leaned ROP > reasonable? I was definitely leaned out=2C albeit conservatively. (Don't > have the instrumentation to support LOP running). Sounds crazy to me. > Anyone care to tell me what reasonable burns in an 0-360 at altitude=2C > FP=2C might be? > > 3. Anything y'all can think of that might reduce the effective volume of > a fuel tank? (A leak=2C I thought....but can't see one - and that doesn't > explain the fact that the tank took 12.5 gallons after having been > conclusively established as empty=2C and unseable fuel drained.) > > 4. OK=2C now it gets really weird. Anyone ever hear of fuel caps being > "sucked" out of the wing=2C in flight? This happened to me y/day=2C and > again (other wing) 2 days prior. I am aware it sounds bizarre. The RV is > just coming off long term sitting around=2C cos I mainly fly my beloved > Harmon Rocket=2C and I wonder if it's possible that caps could get old=2C > and not "spread" when the lever is snapped flush with the top of the > wing. > > All comments from those more experienced in RVs than me would be > welcomed. Me and my RV are just getting to know each other again=2C after > a long time of being unfaithful to her=2C in the Rocket :) > > Cheers > > Andrew > > > ________________________________________________________________________ > ________________________________________________________________________ > ____________________________________________________________ > > > -----Original Message----- > From: owner-rv-list-server@matronics.com > [mailto:owner-rv-list-server@matronics.com] On Behalf Of Sam Buchanan > Sent: Friday=2C April 03=2C 2009 3:01 AM > To: rv-list@matronics.com > Subject: Re: RV-List: Anyone got a couple of RV fuel caps for sale? > > > ACTIVE NZ - Andrew wrote: > > Don't need to be new=2C can replace the 'O' rings....they're for my > > RV-4=2C but I think most RV caps will fit=2C yeah? Will pay anything > reasonable... > > > > Feel free to email me off-list lostpianoplayer@hotmail.com > > > > Thank you > > > > Andrew Fairfax > > > > > http://www.vansaircraft.com/cgi-bin/catalog.cgi?ident=1238679519-14-12& b > rowse=am&product=fuel-cap > > Sam Buchanan > > > > > > > > > =========== =========== =========== =========== > > > _________________________________________________________________ Quick access to your favorite MSN content and Windows Live with Internet Ex plorer 8. http://ie8.msn.com/microsoft/internet-explorer-8/en-us/ie8.aspx?ocid=B037 MSN55C0701A ________________________________ Message 7 _____________________________________ Time: 01:10:50 PM PST US Subject: Re: RV-List: Fuel tank/burn questions From: Doug Gray On Fri, 2009-04-03 at 20:57 +1300, ACTIVE NZ - Andrew wrote: > it only took 12.5 gallons. Kevin's response covers the options. Key question is if you can drain fuel from the 'dry' tank. If you have a fuel gauge, what does it read? Does the alternate tank have the same issue? Consider: (16 - 12.5) leaves 3.5 gallons in the tank. 3.5 gal is about 25% full scale on the Vans fuel gauge that is reasonably accurate at this level, so you are most likely sucking air when fuel is about 25% up the inboard tank rib. My money is on a loose/cracked/damaged fuel pickup. Doug ________________________________ Message 8 _____________________________________ Time: 01:26:21 PM PST US Subject: Re: RV-List: Fuel tank/burn questions From: Doug Gray On Sat, 2009-04-04 at 06:08 +1000, Doug Gray wrote: > > > > it only took 12.5 gallons. Wait a minute - are you in New Zealand? 12.5 Imp Gallons * 1.2 => 15 USG You might also be losing fuel - check tank & gascolator drains under pressure, perhaps through the poorly sealed caps. Seems to me you are being punished for flirting with a Rocket! ________________________________ Message 9 _____________________________________ Time: 01:36:26 PM PST US From: "Brian Meyette" Subject: RV-List: Wire splicing technique I've been using a wire splicing technique that I think works very well. As part of doing a bunch more splicing recently, when I added my SDS ECU into my STi engine wiring harness, I took pics & just created a new page that shows the products and techniques used. Any feedback from it, please let me know. www.meyette.us/crimping.htm hope it's helpful, brian ________________________________ Message 10 ____________________________________ Time: 02:00:23 PM PST US From: "Michael" Subject: Re: RV-List: Wire splicing technique Just use environmental splices that we use in all of our installs that require corrosion proof areas. http://www.edmo.com/index.php?module=products&func=display&prod_id= 18889&disp=desc&cat_id=440 ----- Original Message ----- From: Brian Meyette To: Brian Meyette Sent: Friday, April 03, 2009 1:35 PM Subject: RV-List: Wire splicing technique I've been using a wire splicing technique that I think works very well. As part of doing a bunch more splicing recently, when I added my SDS ECU into my STi engine wiring harness, I took pics & just created a new page that shows the products and techniques used. Any feedback from it, please let me know. www.meyette.us/crimping.htm hope it's helpful, brian ________________________________ Message 11 ____________________________________ Time: 02:59:23 PM PST US From: linn Subject: Re: RV-List: Wire splicing technique Brian Meyette wrote: > I've been using a wire splicing technique that I think works very > well. As part of doing a bunch more splicing recently, when I added > my SDS ECU into my STi engine wiring harness, I took pics & just > created a new page that shows the products and techniques used. Any > feedback from it, please let me know. Excellent! The only thing I can add is that you can get round lacing cord (so you don't have to keep 'untwisting' the flat cord) ...... look for 'rib stitch' cord .... used to stitch the fabric to wing ribs. Linn > www.meyette.us/crimping.htm > hope it's helpful, > brian > > * > > > * > ------------------------------------------------------------------------ > > > Checked by AVG - www.avg.com > > ________________________________ Message 12 ____________________________________ Time: 03:40:36 PM PST US From: Denis Walsh Subject: Re: RV-List: Fuel tank/burn questions first of all my money is with Doug's Imperial answer. As to cap sucking. My six has blown (had sucked) off a couple tank caps over the years. I now carry a spare with me. In my case they were left loose, either by the fueler or by me. The good news is that in coordinated flight and reasonable attitudes and speeds, the fuel quits drooling after only a half gallon or so. I should add that I have also fliight checked another fascinating condition, which is having the fuel cap slightly cocked in the receptacle, but latched snug. This can also result in fuel going overboard, due to the aforementioned low pressure area over the cap. Again the fuel drool stops after a short time in coordinated flight, most likely because of the fortuitous dihedral of the Van's wing. Denis On Apr 3, 2009, at 2:24 , Doug Gray wrote: > On Sat, 2009-04-04 at 06:08 +1000, Doug Gray wrote: >> >>> it only took 12.5 gallons. > > Wait a minute - are you in New Zealand? 12.5 Imp Gallons * 1.2 => > 15 USG > > You might also be losing fuel - check tank & gascolator drains under > pressure, perhaps through the poorly sealed caps. > > Seems to me you are being punished for flirting with a Rocket! > > ________________________________ Message 13 ____________________________________ Time: 03:42:30 PM PST US Subject: RV-List: Clarification on fuel tank issue From: "ACTIVE NZ - Andrew" Thx for all the input...much appreciated. Yep, I'm in NZ. We work in litres, but I translated to US gallons (not imperial). Yep, I'm probably being punished for flirting with a Rocket, but it's been a wicked flirtation :) And my Rocket has given me >500 trouble free hours till first major problem -now AOG, hence dusting off RV-4. On the other hand, I've had the RV4 for about 10 years, and have had more problems than I care to count, including TWO full, to-the-ground, engine failures. We're pretty sure the cause was carb icing, (plenty of fuel in tanks and carb bowl, mags OK, etc etc) and new carb heat system now installed. I mention this, in case it's relevant to current case. Fuel gauges are U/S, so no reading available. Don't know about alternative tank yet - will be investigating shortly. To be clear, I DID drain remaing fuel after the fuel starvation event, through fuel tank drain, and it was less than half a gallon at the very most - that tank was EMPTY. And it took 50 liters, taking several minutes cos of the aero baffles, which I guesstimated to 12.5 gallons. Just looked it up - 50 litres is actually a shade over US 13 gallons. I guess I'll inspecting the interior of the tank, although this all seems inexplicable at the mo. And, NB, even with only taking 13 gallons, not 16, it sounds like she shouldn't have burned anything like that in an hour?? Will investigate all the suggestions given. Feel free to email me, on or off-list, if this cluster of symptoms lights up any sudden Eureka moments. andrew ________________________________ From: owner-rv-list-server@matronics.com [mailto:owner-rv-list-server@matronics.com] On Behalf Of Doug Gray Sent: Saturday, April 04, 2009 9:15 AM Subject: Re: RV-List: Fuel tank/burn questions On Fri, 2009-04-03 at 20:57 +1300, ACTIVE NZ - Andrew wrote: it only took 12.5 gallons. Kevin's response covers the options. Key question is if you can drain fuel from the 'dry' tank. If you have a fuel gauge, what does it read? Does the alternate tank have the same issue? Consider: (16 - 12.5) leaves 3.5 gallons in the tank. 3.5 gal is about 25% full scale on the Vans fuel gauge that is reasonably accurate at this level, so you are most likely sucking air when fuel is about 25% up the inboard tank rib. My money is on a loose/cracked/damaged fuel pickup. Doug ________________________________ Message 14 ____________________________________ Time: 07:48:46 PM PST US From: Jerry Springer Subject: Re: RV-List: Clarification on fuel tank issue Actually it is easy to put 13 gal through an O-360 per hour at WOT if you are not leaned aggressively. What RPM are you seeing at 5000 ft at WOT? My RV-6 with an O-360 fixed pitch well easily burn 10 GPH @ 2500 rpm if not leaned heavily. I have been flying it just a couple months short of 20 years so have a pretty good idea of fuel burn :) ACTIVE NZ - Andrew wrote: > Thx for all the input...much appreciated. > > Yep, I'm in NZ. We work in litres, but I translated to US gallons (not > imperial). > > Yep, I'm probably being punished for flirting with a Rocket, but it's > been a wicked flirtation :) And my Rocket has given me >500 trouble > free hours till first major problem -now AOG, hence dusting off RV-4. > > On the other hand, I've had the RV4 for about 10 years, and have had > more problems than I care to count, including TWO full, to-the-ground, > engine failures. We're pretty sure the cause was carb icing, (plenty > of fuel in tanks and carb bowl, mags OK, etc etc) and new carb heat > system now installed. I mention this, in case it's relevant to current > case. > > Fuel gauges are U/S, so no reading available. Don't know about > alternative tank yet - will be investigating shortly. > > To be clear, I DID drain remaing fuel after the fuel starvation event, > through fuel tank drain, and it was less than half a gallon at the > very most - that tank was EMPTY. And it took 50 liters, taking several > minutes cos of the aero baffles, which I guesstimated to 12.5 gallons. > Just looked it up - 50 litres is actually a shade over US 13 gallons. > > I guess I'll inspecting the interior of the tank, although this > all seems inexplicable at the mo. And, NB, even with only taking 13 > gallons, not 16, it sounds like she shouldn't have burned anything > like that in an hour?? > > Will investigate all the suggestions given. Feel free to email me, on > or off-list, if this cluster of symptoms lights up any sudden Eureka > moments. > > > andrew > > ** > > ------------------------------------------------------------------------ > *From:* owner-rv-list-server@matronics.com > [mailto:owner-rv-list-server@matronics.com] *On Behalf Of *Doug Gray > *Sent:* Saturday, April 04, 2009 9:15 AM > *To:* rv-list@matronics.com > *Subject:* Re: RV-List: Fuel tank/burn questions > > On Fri, 2009-04-03 at 20:57 +1300, ACTIVE NZ - Andrew wrote: >> it only took 12.5 gallons. > Kevin's response covers the options. Key question is if you can drain > fuel from the 'dry' tank. > > If you have a fuel gauge, what does it read? > Does the alternate tank have the same issue? > > Consider: (16 - 12.5) leaves 3.5 gallons in the tank. 3.5 gal is about > 25% full scale on the Vans fuel gauge that is reasonably accurate at > this level, so you are most likely sucking air when fuel is about 25% > up the inboard tank rib. My money is on a loose/cracked/damaged fuel > pickup. > > Doug > * > > href="http://www.matronics.com/Navigator?RV-List">http://www.matronics.com/Navigator?RV-List > href="http://forums.matronics.com">http://forums.matronics.com > href="http://www.matronics.com/contribution">http://www.matronics.com/c > * > * > > > * ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rv-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RV-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/rv-list Browse Digests http://www.matronics.com/digest/rv-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.