---------------------------------------------------------- Kitfox-List Digest Archive --- Total Messages Posted Tue 09/20/11: 8 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:12 PM - 912s will not stay running (Shane Sather) 2. 07:21 PM - Re: 912s will not stay running (b d) 3. 07:34 PM - Re: 912s will not stay running (Michael Kraus) 4. 07:53 PM - Re: 912s will not stay running (Shane Sather) 5. 08:00 PM - Re: 912s will not stay running (Shane Sather) 6. 09:15 PM - Re: 912s will not stay running (Paul A. Franz, P.E.) 7. 09:39 PM - Re: 912s will not stay running (Lowell Fitt) 8. 10:25 PM - Re: 912s will not stay running (b d) ________________________________ Message 1 _____________________________________ Time: 06:12:32 PM PST US From: "Shane Sather" Subject: Kitfox-List: 912s will not stay running Hello Listers My 912s is giving me a hard time, it will not stay running. I prime it, it starts and then runs for a minuet or so and then it is out of fuel. I thought it was the fuel pump but that is not the case (i replaced the old one). It is almost like the carbs are not creating vacuum or are plugged or blocked somehow. It is odd as it was running fine when I landed last time. Since that time the Kitfox has been dry docked. We did have a very big wind storm and the plane was rocking on the dock. Could something have shaken loose or got stuck. There is fuel in the wing tanks, fuel to small tank (it is full) behind the seats. There was fuel in the line to the pump when I changed the pump. But the main lines to the carbs do not appear to be full. It seems that the only fuel getting to the carbs is from the priming. Any ideas? Thanks Shane ________________________________ Message 2 _____________________________________ Time: 07:21:24 PM PST US Subject: Re: Kitfox-List: 912s will not stay running From: b d There is not enough information to isolate the problem but here is a place to begin. With today's fuels as they are, they evaporate and sometimes leave a residue in the idle jets and other small ports. Try increasing your throttle setting above the idle range and see if it runs then. If so it is probably clogged idle jets. If not take your main fuel line off and make sure you have good flow to the carb(s) for a continued length of time. Let it run and make sure there is no blockage or restriction anywhere. If that is clear, then your problem is isolated to the carb or fuel injection system. From there you had better have a good mechanic look further as you do not have the skills for that. Hence you wouldn't be asking this question . . not to hurt your feelings but I even hesitate telling you to take the main fuel line off. Maybe a good A&P mechanic is needed as I think about it and I stress "good A&P mechanic" Bruce On Tue, Sep 20, 2011 at 6:09 PM, Shane Sather wrote: > Hello Listers > > My 912s is giving me a hard time, it will not stay running. I prime it, it > starts and then runs for a minuet or so and then it is out of fuel. I > thought it was the fuel pump but that is not the case (i replaced the old > one). It is almost like the carbs are not creating vacuum or are plugged or > blocked somehow. It is odd as it was running fine when I landed last time. > Since that time the Kitfox has been dry docked. We did have a very big wind > storm and the plane was rocking on the dock. Could something have shaken > loose or got stuck. There is fuel in the wing tanks, fuel to small tank (it > is full) behind the seats. There was fuel in the line to the pump when I > changed the pump. But the main lines to the carbs do not appear to be full. > It seems that the only fuel getting to the carbs is from the priming. Any > ideas? > > Thanks Shane > > * > > * > > ________________________________ Message 3 _____________________________________ Time: 07:34:46 PM PST US Subject: Re: Kitfox-List: 912s will not stay running From: Michael Kraus Are your tank vent lines plugged? Sent from my iPhone On Sep 20, 2011, at 10:17 PM, b d wrote: > There is not enough information to isolate the problem but here is a place to begin. With today's fuels as they are, they evaporate and sometimes leav e a residue in the idle jets and other small ports. Try increasing your thro ttle setting above the idle range and see if it runs then. If so it is proba bly clogged idle jets. If not take your main fuel line off and make sure you have good flow to the carb(s) for a continued length of time. Let it run an d make sure there is no blockage or restriction anywhere. If that is clear, t hen your problem is isolated to the carb or fuel injection system. =46rom th ere you had better have a good mechanic look further as you do not have the s kills for that. Hence you wouldn't be asking this question . . not to hurt y our feelings but I even hesitate telling you to take the main fuel line off. Maybe a good A&P mechanic is needed as I think about it and I stress "goo d A&P mechanic" > > Bruce > > > > On Tue, Sep 20, 2011 at 6:09 PM, Shane Sather w rote: > Hello Listers > > My 912s is giving me a hard time, it will not stay running. I prime it, it starts and then runs for a minuet or so and then it is out of fuel. I thoug ht it was the fuel pump but that is not the case (i replaced the old one). I t is almost like the carbs are not creating vacuum or are plugged or blocked somehow. It is odd as it was running fine when I landed last time. Since th at time the Kitfox has been dry docked. We did have a very big wind storm an d the plane was rocking on the dock. Could something have shaken loose or go t stuck. There is fuel in the wing tanks, fuel to small tank (it is full) be hind the seats. There was fuel in the line to the pump when I changed the pu mp. But the main lines to the carbs do not appear to be full. It seems that t he only fuel getting to the carbs is from the priming. Any ideas? > > Thanks Shane > > > arget="_blank">http://www.matronics.com/Navigator?Kitfox-List > tp://forums.matronics.com > _blank">http://www.matronics.com/contribution > > > > ========================== ========= ========================== ========= ========================== ========= ========================== ========= > ________________________________ Message 4 _____________________________________ Time: 07:53:53 PM PST US From: "Shane Sather" Subject: Re: Kitfox-List: 912s will not stay running If you are referring to the gas cap vents I did check them and they are clear. Thanks Shane From: Michael Kraus Sent: Tuesday, September 20, 2011 8:32 PM Subject: Re: Kitfox-List: 912s will not stay running Are your tank vent lines plugged? Sent from my iPhone On Sep 20, 2011, at 10:17 PM, b d wrote: There is not enough information to isolate the problem but here is a place to begin. With today's fuels as they are, they evaporate and sometimes leave a residue in the idle jets and other small ports. Try increasing your throttle setting above the idle range and see if it runs then. If so it is probably clogged idle jets. If not take your main fuel line off and make sure you have good flow to the carb(s) for a continued length of time. Let it run and make sure there is no blockage or restriction anywhere. If that is clear, then your problem is isolated to the carb or fuel injection system. From there you had better have a good mechanic look further as you do not have the skills for that. Hence you wouldn't be asking this question . . not to hurt your feelings but I even hesitate telling you to take the main fuel line off. Maybe a good A&P mechanic is needed as I think about it and I stress "good A&P mechanic" Bruce On Tue, Sep 20, 2011 at 6:09 PM, Shane Sather wrote: Hello Listers My 912s is giving me a hard time, it will not stay running. I prime it, it starts and then runs for a minuet or so and then it is out of fuel. I thought it was the fuel pump but that is not the case (i replaced the old one). It is almost like the carbs are not creating vacuum or are plugged or blocked somehow. It is odd as it was running fine when I landed last time. Since that time the Kitfox has been dry docked. We did have a very big wind storm and the plane was rocking on the dock. Could something have shaken loose or got stuck. There is fuel in the wing tanks, fuel to small tank (it is full) behind the seats. There was fuel in the line to the pump when I changed the pump. But the main lines to the carbs do not appear to be full. It seems that the only fuel getting to the carbs is from the priming. Any ideas? Thanks Shane arget="_blank">http://www.matronics.com/Navigator?Kitfox-List tp://forums.matronics.com _blank">http://www.matronics.com/contribution ========= href="http://www.matronics.com/Navigator?Kitfox-List">http://www.matron ics.com/Navigator?Kitfox-List ========= ums.matronics.com">http://forums.matronics.com ========= http://www.matronics.com/contribution">http://www.matronics.com/contribut ion ========= ________________________________ Message 5 _____________________________________ Time: 08:00:28 PM PST US From: "Shane Sather" Subject: Re: Kitfox-List: 912s will not stay running Thanks for your input. I will check further into the fuel line. It is not a difficult task to check further I was just asking for possible suggestions. And blockage of some sort between fuel pump and carbs or in carbs seems very likely. Shane From: b d Sent: Tuesday, September 20, 2011 8:17 PM Subject: Re: Kitfox-List: 912s will not stay running There is not enough information to isolate the problem but here is a place to begin. With today's fuels as they are, they evaporate and sometimes leave a residue in the idle jets and other small ports. Try increasing your throttle setting above the idle range and see if it runs then. If so it is probably clogged idle jets. If not take your main fuel line off and make sure you have good flow to the carb(s) for a continued length of time. Let it run and make sure there is no blockage or restriction anywhere. If that is clear, then your problem is isolated to the carb or fuel injection system. From there you had better have a good mechanic look further as you do not have the skills for that. Hence you wouldn't be asking this question . . not to hurt your feelings but I even hesitate telling you to take the main fuel line off. Maybe a good A&P mechanic is needed as I think about it and I stress "good A&P mechanic" Bruce On Tue, Sep 20, 2011 at 6:09 PM, Shane Sather wrote: Hello Listers My 912s is giving me a hard time, it will not stay running. I prime it, it starts and then runs for a minuet or so and then it is out of fuel. I thought it was the fuel pump but that is not the case (i replaced the old one). It is almost like the carbs are not creating vacuum or are plugged or blocked somehow. It is odd as it was running fine when I landed last time. Since that time the Kitfox has been dry docked. We did have a very big wind storm and the plane was rocking on the dock. Could something have shaken loose or got stuck. There is fuel in the wing tanks, fuel to small tank (it is full) behind the seats. There was fuel in the line to the pump when I changed the pump. But the main lines to the carbs do not appear to be full. It seems that the only fuel getting to the carbs is from the priming. Any ideas? Thanks Shane arget="_blank">http://www.matronics.com/Navigator?Kitfox-List tp://forums.matronics.com _blank">http://www.matronics.com/contribution ________________________________ Message 6 _____________________________________ Time: 09:15:13 PM PST US Subject: Re: Kitfox-List: 912s will not stay running From: "Paul A. Franz, P.E." On Tue, September 20, 2011 7:50 pm, Shane Sather wrote: > If you are referring to the gas cap vents I did check them and they are clear. > > Thanks Shane My 2 cents' worth -- I'd suspect floats sticking or needle stuck. It's not really too difficult to carefully remove the float bowl to see if the float drops down as it should and that the needle is away from the seat. If either is sticking, cleaning the pivot pin or the needle and seat with isopropyl (rubbing) alcohol should do the trick. It the needle has some polymer tip as some do, I can't say if it is OK or not to get rubbing alcohol on it but if it is brass, no problem. After that, when the engine runs the normal fuel flow should keep it clean. I'm assuming that the gasoline isn't failing due to age and heat exposure. When I've seen that condition (old fuel) it smells odd and makes the engine almost impossible to start and you get detonation when it does start. This doesn't happen over a few day though. But it can happen in a few weeks. So, check that you have fuel flowing to the float bowls and that the floats aren't sticking and the needle isn't stuck to the seat. -- Paul A. Franz, P.E. PAF Consulting Engineers Office 425.440.9505 Cell 425.241.1618 ________________________________ Message 7 _____________________________________ Time: 09:39:05 PM PST US From: "Lowell Fitt" Subject: Re: Kitfox-List: 912s will not stay running One thought, and likely not the answer you are seeking. I once had a fuel flow issue that led to a rough running engine on departure and a return to the airport. I mention it because you say you replaced your fuel pump. What I did is replace all engine compartment fuel lines, then when tightening the firesleeve clamps, crimped the fuel line to almost no fuel flow. I guess the question is, have you visually inspected the fuel lines to see if you can see light at the end of the "tunnel". That is how I found my problem as everything appeared fine from the external view point, but when holding the lines out straight, I couldn't see any opening in the lines. There was another guy years ago that had double clamps on all fuel lines and he had a habit of tightening a bit more at each annual. He finally did what I did, but using a different method. Lowell From: Shane Sather Sent: Tuesday, September 20, 2011 6:09 PM Subject: Kitfox-List: 912s will not stay running Hello Listers My 912s is giving me a hard time, it will not stay running. I prime it, it starts and then runs for a minuet or so and then it is out of fuel. I thought it was the fuel pump but that is not the case (i replaced the old one). It is almost like the carbs are not creating vacuum or are plugged or blocked somehow. It is odd as it was running fine when I landed last time. Since that time the Kitfox has been dry docked. We did have a very big wind storm and the plane was rocking on the dock. Could something have shaken loose or got stuck. There is fuel in the wing tanks, fuel to small tank (it is full) behind the seats. There was fuel in the line to the pump when I changed the pump. But the main lines to the carbs do not appear to be full. It seems that the only fuel getting to the carbs is from the priming. Any ideas? Thanks Shane ________________________________ Message 8 _____________________________________ Time: 10:25:26 PM PST US Subject: Re: Kitfox-List: 912s will not stay running From: b d What I outlined by removing the fuel line and check the fuel flow to the carb will segregate/isolate the problem between the fuel system and the carburetor that is if you don't have two problems. Rather than a visual inspection as mentioned to find a crimped line, if you do this simple procedure it will tell you where your problem is and where it's not. If you have good fuel flow down to your carburetor, your problem is in the carburetor. If not it's up between there and the tank which requires more diagnoses. I disagree with the PE. An inexperienced person, including a PE should not be experimenting on an aircraft carburetor to save a dime. I also disagree with the PE that the fuel needs to go bad to have a clogging problem. That is simply not true. Fuel won't go bad in a few weeks but it will evaporate in a carb float bowl and leave residue in the jets. All lawn mower mechanics on up know this. The fuel in the tank can be perfectly good while the fuel in the carb float bowl many times will evaporate (especially if left in the heat) and leave the jets plugged up. So, with that said, the smell of fuel only indicates really old fuel but is no indication or help with the problem you are describing. You most likely have clogged jets found in the summer heat in every gas engine today. The question is, do you have the expertise to DIY your own carb? Again, not to hurt your feelings but I would say no or you would have known how to isolate this simple problem, and so should the PE have known how to segregate and isolate the problem. It's very logical and systematic. No superstition or black magic, no voodoo or PE required. . . does the fuel make it to the carb or not . . .??? It's as simple as "can water run downhill?" Not brain surgery . . . :-) Bruce On Tue, Sep 20, 2011 at 9:12 PM, Paul A. Franz, P.E. wrote: > paul@eucleides.com> > > > On Tue, September 20, 2011 7:50 pm, Shane Sather wrote: > > If you are referring to the gas cap vents I did check them and they are > clear. > > > > Thanks Shane > > My 2 cents' worth -- I'd suspect floats sticking or needle stuck. It's not > really too > difficult to carefully remove the float bowl to see if the float drops down > as it > should and that the needle is away from the seat. If either is sticking, > cleaning the > pivot pin or the needle and seat with isopropyl (rubbing) alcohol should do > the trick. > It the needle has some polymer tip as some do, I can't say if it is OK or > not to get > rubbing alcohol on it but if it is brass, no problem. After that, when the > engine runs > the normal fuel flow should keep it clean. I'm assuming that the gasoline > isn't > failing due to age and heat exposure. When I've seen that condition (old > fuel) it > smells odd and makes the engine almost impossible to start and you get > detonation when > it does start. This doesn't happen over a few day though. But it can happen > in a few > weeks. > > So, check that you have fuel flowing to the float bowls and that the floats > aren't > sticking and the needle isn't stuck to the seat. > > -- > Paul A. Franz, P.E. > PAF Consulting Engineers > Office 425.440.9505 > Cell 425.241.1618 > > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message kitfox-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Kitfox-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/kitfox-list Browse Digests http://www.matronics.com/digest/kitfox-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.