 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
shanesather(at)netkaster.
Guest
|
 Posted: Tue Sep 20, 2011 5:12 pm Post subject: 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
[quote][b]
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
|
|
| Back to top |
|
 |
gpabruce(at)gmail.com
Guest
|
| Posted: Tue Sep 20, 2011 6:21 pm Post subject: 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 <shanesather(at)netkaster.ca (shanesather(at)netkaster.ca)> wrote:
[quote] 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
| Quote: |
arget="_blank">http://www.matronics.com/Navigator?Kitfox-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution
|
[b]
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
|
|
| Back to top |
|
|
n223rv(at)wolflakeairport
Guest
|
| Posted: Tue Sep 20, 2011 6:34 pm Post subject: 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 <gpabruce(at)gmail.com (gpabruce(at)gmail.com)> wrote:
[quote]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 <[url=mailto:shanesather(at)netkaster.ca]shanesather(at)netkaster.ca (shanesather(at)netkaster.ca)[/url]> wrote:
| Quote: | 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
===================================
href="http://www.matronics.com/Navigator?Kitfox-List">http://www.matronics.com/Navigator?Kitfox-List
===================================
ums.matronics.com">http://forums.matronics.com
===================================
http://www.matronics.com/contribution">http://www.matronics.com/contribution
===================================
|
[b]
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
|
|
| Back to top |
|
|
shanesather(at)netkaster.
Guest
|
| Posted: Tue Sep 20, 2011 6:53 pm Post subject: 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 (n223rv(at)wolflakeairport.net)
Sent: Tuesday, September 20, 2011 8:32 PM
To: kitfox-list(at)matronics.com (kitfox-list(at)matronics.com)
Subject: Re: 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 <gpabruce(at)gmail.com (gpabruce(at)gmail.com)> wrote:
[quote] 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 <[url=mailto:shanesather(at)netkaster.ca]shanesather(at)netkaster.ca (shanesather(at)netkaster.ca)[/url]> wrote:
| Quote: | 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
| Quote: |
arget="_blank">http://www.matrontp://forums.matronics.com
_blank">http://www.matronics.com/c
|
|
href="http://www.matronics.com/Navigator?Kitfox-List">http://www.matronhref="http://forums.matronics.com">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/c
[b]
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
|
|
| Back to top |
|
|
shanesather(at)netkaster.
Guest
|
| Posted: Tue Sep 20, 2011 7:00 pm Post subject: 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 (gpabruce(at)gmail.com)
Sent: Tuesday, September 20, 2011 8:17 PM
To: kitfox-list(at)matronics.com (kitfox-list(at)matronics.com)
Subject: Re: 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 <shanesather(at)netkaster.ca (shanesather(at)netkaster.ca)> wrote:
| Quote: | 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
| Quote: |
arget="_blank">http://www.matronics.com/Navigator?Kitfox-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution
|
|
[quote]
href="http://www.matronics.com/Navigator?Kitfox-List">http://www.matronhref="http://forums.matronics.com">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/c
[b]
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
|
|
| Back to top |
|
|
Paul A. Franz, P.E.
Joined: 02 Dec 2008
Posts: 280
Location: Bellevue WA
|
| Posted: Tue Sep 20, 2011 8:15 pm Post subject: 912s will not stay running |
|
|
On Tue, September 20, 2011 7:50 pm, Shane Sather wrote:
| Quote: | 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
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
_________________
Paul A. Franz, P.E.
Registration/Aircraft - N14UW/Merlin GT
Engine/Prop - Rotax 914/NSI CAP
Bellevue WA
425.241.1618 Cell
425.440.9505 Office |
|
| Back to top |
|
|
lcfitt(at)sbcglobal.net
Guest
|
| Posted: Tue Sep 20, 2011 8:39 pm Post subject: 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 (shanesather(at)netkaster.ca)
Sent: Tuesday, September 20, 2011 6:09 PM
To: kitfox list (kitfox-list(at)matronics.com)
Subject: 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
[quote]
href="http://www.matronics.com/Navigator?Kitfox-List">http://www.matronhref="http://forums.matronics.com">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/c
[b]
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
|
|
| Back to top |
|
|
gpabruce(at)gmail.com
Guest
|
| Posted: Tue Sep 20, 2011 9:25 pm Post subject: 912s will not stay running |
|
|
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. <paul(at)eucleides.com (paul(at)eucleides.com)> wrote:
[quote]--> Kitfox-List message posted by: "Paul A. Franz, P.E." <paul(at)eucleides.com (paul(at)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 [url=tel:425.440.9505]425.440.9505[/url]
Cell [url=tel:425.241.1618]425.241.1618[/url]
===========
target="_blank">http://www.matronics.com/Navigator?Kitfox-List
===========
http://forums.matronics.com
===========
le, List Admin.
="_blank">http://www.matronics.com/contribution
===========
[b]
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
|
|
| Back to top |
|
|
shanesather(at)netkaster.
Guest
|
| Posted: Wed Sep 21, 2011 5:49 am Post subject: 912s will not stay running |
|
|
Thanks Bruce, this is the approach I am taking too (checking the fuel supply first).
Just so everyone knows the conditions I live in.
I live in the High Arctic, we don’t have hot summers and the flying season is pretty much done now. I only operate on floats and the season is short. Our fuel has no alcohol in it and likely never will due to our weather conditions. There is no handy service center to go to for assistance and we are pretty much on our own for repairs. Any major repairs would require me removing engine and shipping it south to a service center. Less major items such as installing improvements (I removed and reinstalled the old clutch when I had it updated, by a service center, with the slipper clutch. The 912s has been a very reliable engine and to date has only had one other issue (electrical) and that was sorted out through advice from this forum as it was a similar experience. Hence the new request for advice. As with any advice it has to be weighted for it usefulness and that can be based on experience and “profession” advice when available.
Back to my issue I am just trying to sort it out before the snow flies rather than put the plane away in its current condition. The fuel issue is just a little odd to me though as it was working fine after the last flight and then after two weeks docked there is a problem.
Thanks again for the advice and I will let all know how it turns out if I get the opportunity to resolve before freeze up.
Shane
From: b d (gpabruce(at)gmail.com)
Sent: Tuesday, September 20, 2011 11:22 PM
To: kitfox-list(at)matronics.com (kitfox-list(at)matronics.com)
Subject: Re: 912s will not stay running
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. <paul(at)eucleides.com (paul(at)eucleides.com)> wrote:
| Quote: | --> Kitfox-List message posted by: "Paul A. Franz, P.E." <paul(at)eucleides.com (paul(at)eucleides.com)>
On Tue, September 20, 2011 7:50 pm, Shane Sather wrote:
| Quote: | 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 [url=tel:425.440.9505]425.440.9505[/url]
Cell [url=tel:425.241.1618]425.241.1618[/url]
===========
target="_blank">http://www.matronics.com/Navigator?Kitfox-List
===========
http://forums.matronics.com
===========
le, List Admin.
="_blank">http://www.matronics.com/contribution
===========
|
[quote]
href="http://www.matronics.com/Navigator?Kitfox-List">http://www.matronhref="http://forums.matronics.com">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/c
[b]
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
|
|
| Back to top |
|
|
gpabruce(at)gmail.com
Guest
|
| Posted: Wed Sep 21, 2011 6:47 am Post subject: 912s will not stay running |
|
|
Shane,
I see your dilemma more clearly now. I don't have a schematic of your exact
fuel system or I could better help you. It is just a matter of
systematically isolating where the stoppage or restriction is.
First off . . . check to see if your problem is still there or has it gone
away without any help . . . so first off, I would start the engine to
confirm that your problem is still there. When running the engine,
presuming it runs a short time, try advancing the throttle as you start it
again to see if it runs at a higher rpm but not at a low rpm (idle range).
Also do you have a mixture control with idle cutoff? I don't know about the
912 so let me know. Check to make sure that your idle cutoff is not in the
off position and your mixture is full rich. (make sure your cable is not
broken or slipping too)
Do you have a fuel pump, a strainer, a shut off valve and/or selector valve
in the loop?
If you had or could point to a drawing of your fuel system from the internet
I could make a systematic check list for you. Also a good thing if you have
one and I don't know but is there a plug in the bottom of your float bowl
you can remove to let the fuel drain out there? Many carbs have them
especially on aircraft. But first off after confirming you still have the
same problem, I would just take the line off at the carb and make sure you
have plenty of fuel at that point so you know which direction to
troubleshoot. If you seem to have plenty of fuel to the carb then
investigate the carb further and if it has a plug in the bottom, pull it out
and see if your fuel continues to run out the carb. It won't be as fast as
the fuel line because it will be going through the needle and seat and
possible a small filter at the very place where your line connects. If you
feel there is adequate fuel running out the drain plug, then it could be the
jets are plugged . . . If not, it could be the inline filter or it could be
the needle and seat are stuck. Sometimes a soft wrap with a plastic handle
will jar it lose but remember that is not the fix to the problem. It still
should be taken apart and cleaned along wit the inline filter if it has
one.
See if you can find a schematic or describe one for me so I can better see
your system if these things don't work. I have a dumb question, since you
mentioned your in the arctic, is there any chance you could have had water
in your fuel that froze? I live in Las Vegas and it's still hot here so I
didn't think of you being in the arctic.
BTW, if you are on floats, I presume you're plane is on the water so be
cautious when removing your carb. If you see you have to, I would take it
completely off and disassemble it and reassemble it somewhere else so you
don't lose anything. I guess you're used to doing that anyway. Do you have
some sort of shelter there you keep it in? I would love to see some pics
from up there if you could. Sounds like a nice place to live . . .and what
do you do up there for a living?
Bruce
On Wed, Sep 21, 2011 at 6:46 AM, Shane Sather <shanesather(at)netkaster.ca>wrote:
[quote] Thanks Bruce, this is the approach I am taking too (checking the fuel
supply first).
Just so everyone knows the conditions I live in.
I live in the High Arctic, we don’t have hot summers and the flying season
is pretty much done now. I only operate on floats and the season is short
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
|
|
| Back to top |
|
|
lcfitt(at)sbcglobal.net
Guest
|
| Posted: Wed Sep 21, 2011 7:20 am Post subject: 912s will not stay running |
|
|
Bruce,
With all due respect, have you ever seen a Rotax 912 engine let alone work on one? Are you aware of the basic plumbing design of this application? Part of your earlier comment referring to the possibility of injector issues implies that your responses are generic and in fact may have no application to this specific problem. To imply that if someone posts question to this list they are automatically disqualified from working on their airplane is disrespectful nonsense.
Lowell
From: b d (gpabruce(at)gmail.com)
Sent: Tuesday, September 20, 2011 10:22 PM
To: kitfox-list(at)matronics.com (kitfox-list(at)matronics.com)
Subject: Re: 912s will not stay running
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. <paul(at)eucleides.com (paul(at)eucleides.com)> wrote:
[quote]--> Kitfox-List message posted by: "Paul A. Franz, P.E." <paul(at)eucleides.com (paul(at)eucleides.com)>
On Tue, September 20, 2011 7:50 pm, Shane Sather wrote:
| Quote: | 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 [url=tel:425.440.9505]425.440.9505[/url]
Cell [url=tel:425.241.1618]425.241.1618[/url]
===========
target="_blank">http://www.matronics.com/Navigator?Kitfox-List
===========
http://forums.matronics.com
===========
le, List Admin.
="_blank">http://www.matronics.com/contribution
===========
title="http://www.matronics.com/Navigator?Kitfox-List
CTRL + Click to follow link" href="http://www.matronics.com/Navigator?Kitfox-List">http://www.matronhref="http://forums.matronics.com">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/c
[b]
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
|
|
| Back to top |
|
|
pwmac(at)sisna.com
Guest
|
| Posted: Wed Sep 21, 2011 7:42 am Post subject: 912s will not stay running |
|
|
Hmmm, Are you guys building airplanes without a fuel pressure gauge?
10-4 Lowell.
Replace the fuel lines regulraly, especially if not using SAE auto lines.
Of course you could repeat the fuel flow test like the one done before first flight.
PaulW
=====
At 10:36 PM 9/20/2011, you wrote:
[quote] 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 (shanesather(at)netkaster.ca)
Sent: Tuesday, September 20, 2011 6:09 PM
To: kitfox list (kitfox-list(at)matronics.com)
Subject: 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
[b]
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
|
|
| Back to top |
|
|
gpabruce(at)gmail.com
Guest
|
| Posted: Wed Sep 21, 2011 9:33 am Post subject: 912s will not stay running |
|
|
Shane, My information indicates you may have a manual fuel pump (engine driven pump I presume they mean). Is this what you said you changed out with a new one? Did you test the old one to verify if it had a problem? I would and if it didn't have a problem you may want to save it as a spare.
Do you have a fuel pressure gauge on the panel? and if so what does it read?
Bruce
On Tue, Sep 20, 2011 at 6:09 PM, Shane Sather <shanesather(at)netkaster.ca (shanesather(at)netkaster.ca)> wrote:
[quote] 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
| Quote: |
arget="_blank">http://www.matronics.com/Navigator?Kitfox-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution
|
[b]
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
|
|
| Back to top |
|
|
KITFOXZ(at)aol.com
Guest
|
| Posted: Wed Sep 21, 2011 6:25 pm Post subject: 912s will not stay running |
|
|
Shane,
It is not likely that the same problem would occur in both carbs at the same time. Try substituting your fuel source. Bypass the pump and all existing fuel lines by feeding both carbs with fuel by two equal fuel bottles hung over the aircraft on a bridge built of wood or other material. Gravity feed both carbs by connecting with equal fuel tubing. A 1/4 cup of fuel in each bottle will be plenty to confirm the test. I am betting your pump change out is faulty or some other common blockage has occured.
John
In a message dated 9/20/2011 9:12:51 P.M. Eastern Daylight Time, shanesather(at)netkaster.ca writes:
| Quote: | 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
|
[quote][b]
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
|
|
| Back to top |
|
|
redrocketrider
Joined: 13 May 2011
Posts: 67
Location: Nervino airport
|
| Posted: Wed Sep 21, 2011 6:52 pm Post subject: 912s will not stay running |
|
|
Shane, Have you been running auto fuel with ethanol in it? If so your fuel system is deteriorating and coming apart internally ? Bob
[quote] From: KITFOXZ(at)aol.com (KITFOXZ(at)aol.com)
Sent: Wednesday, September 21, 2011 7:22 PM
To: kitfox-list(at)matronics.com (kitfox-list(at)matronics.com)
Subject: Re: 912s will not stay running
Shane,
It is not likely that the same problem would occur in both carbs at the same time. Try substituting your fuel source. Bypass the pump and all existing fuel lines by feeding both carbs with fuel by two equal fuel bottles hung over the aircraft on a bridge built of wood or other material. Gravity feed both carbs by connecting with equal fuel tubing. A 1/4 cup of fuel in each bottle will be plenty to confirm the test. I am betting your pump change out is faulty or some other common blockage has occured.
John
In a message dated 9/20/2011 9:12:51 P.M. Eastern Daylight Time, shanesather(at)netkaster.ca writes:
| Quote: | 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
|
| Quote: |
href="http://www.matronics.com/Navigator?Kitfox-List">http://www.matronhref="http://forums.matronics.com">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/c
|
[b]
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
_________________
Keep the dirty side down/Blue skies. Bob |
|
| Back to top |
|
|
Paul A. Franz, P.E.
Joined: 02 Dec 2008
Posts: 280
Location: Bellevue WA
|
| Posted: Wed Sep 21, 2011 7:14 pm Post subject: 912s will not stay running |
|
|
On Wed, September 21, 2011 7:22 pm, KITFOXZ(at)aol.com wrote:
| Quote: | Shane,
It is not likely that the same problem would occur in both carbs at the
same time. Try substituting your fuel source. Bypass the pump and all
existing fuel lines by feeding both carbs with fuel by two equal fuel bottles
hung over the aircraft on a bridge built of wood or other material. Gravity
feed both carbs by connecting with equal fuel tubing. A 1/4 cup of fuel in
each bottle will be plenty to confirm the test. I am betting your pump
change out is faulty or some other common blockage has occured.
John
|
If the weather contributed, maybe the float bowls are both full of water or worse yet
- ice. Removing the float bowls carefully will let you see if they have water or
contaminants and that ice isn't blocking anything. If the cause is water or ice, after
inspecting and draining the float bowls, my guess is preheating the engine compartment
and running the engine could then relieve the problem.
--
Paul A. Franz, P.E.
PAF Consulting Engineers
Office 425.440.9505
Cell 425.241.1618
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
_________________
Paul A. Franz, P.E.
Registration/Aircraft - N14UW/Merlin GT
Engine/Prop - Rotax 914/NSI CAP
Bellevue WA
425.241.1618 Cell
425.440.9505 Office |
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
