
Corbin
I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).   -- Corbin N33QR
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My cap like this is tan/brown. I cracked one by over tightening it. Take the old cap and go see what it fits!
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I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
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Corbin N33QR
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Looks like one off a 50 Gal food grade barrel
toggle quoted messageShow quoted text
My cap like this is tan/brown. I cracked one by over tightening it. Take the old cap and go see what it fits!
I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
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Corbin N33QR
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Corbin
You read my mind. I have been walking around the hardware store with mine in hand. I am leaning towards 3D printing a couple of replacements. --
Corbin N121CG
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The original container was about a quart size. It came with the kit 35 years ago. Oh, by the way, with my cap when it was cracked, I lost power at full throttle takeoff. When I throttled back to 75% it ran great. Incase that ever happens to you. If the fuel cap is loose or cracked then I don't get enough fuel flow at full power. Your results may be different. I'm running the 1/4" id fuel lines per plans. Some guys have switched to 3/8" id and I suspect the problem will not occur with the larger lines. I'm not sure if there is a partial vacuum at the fuel cap or if the cap is venting the pressure from the ram air fuel vent.
toggle quoted messageShow quoted text
Looks like one off a 50 Gal food grade barrel
My cap like this is tan/brown. I cracked one by over tightening it. Take the old cap and go see what it fits!
I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
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Corbin N33QR
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Corbin
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Sam Hoskins
Corbin,
The bottle cap is a shitty design. Besides the cap cracking, the threads can also crack. With a carbureted engine, when that happens it introduces low pressure into your header tank and winds up having an engine that doesn't want to run too well and it first starts acting up at about three or four hundred feet after takeoff. Then you have to Mayday and see if you can limp around the pattern. If you're lucky you will have a passenger along who will later praise your excellent skills and nerves of steel.
I don't know what happens with a fuel injection engine but if it was me, I wouldn't want to investigate too far. There are a lot of different ways the guys have done fuel caps, not just the one that I use, but mine is pretty simple and you can get parts at any hardware store. There are more elegant methods out there, such as with the Vai-Ez guys may use.
Take care.
Sam
toggle quoted messageShow quoted text
I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
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Corbin N33QR
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Corbin
Agreed. Honestly, I just want to get the conditional signed off before he has to leave town. My understanding is the venting/cracking only affects the carb setups. But I don't want first-hand knowledge of that being incorrect. I suspect that I have been running with mine venting (cracked), without realizing it, for the last year.
Corbin
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On March 15, 2021 at 5:05 PM, Sam Hoskins <sam.hoskins@...> wrote: Corbin,
The bottle cap is a shitty design. Besides the cap cracking, the threads can also crack. With a carbureted engine, when that happens it introduces low pressure into your header tank and winds up having an engine that doesn't want to run too well and it first starts acting up at about three or four hundred feet after takeoff. Then you have to Mayday and see if you can limp around the pattern. If you're lucky you will have a passenger along who will later praise your excellent skills and nerves of steel.
I don't know what happens with a fuel injection engine but if it was me, I wouldn't want to investigate too far. There are a lot of different ways the guys have done fuel caps, not just the one that I use, but mine is pretty simple and you can get parts at any hardware store. There are more elegant methods out there, such as with the Vai-Ez guys may use.
Take care.
Sam I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
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Corbin N33QR
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Corbin N121CG
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Here's the set up on mine. Using a modified plumbing cap. There is a rubber seal at the top of the thread The inside of the filler neck has a vent tube in it that will go to the rest of the system, I haven't figured out what the original builder was intending but I think I might modify the cap by installing a vented tab into the slot.
toggle quoted messageShow quoted text
Agreed. Honestly, I just want to get the conditional signed off before he has to leave town. My understanding is the venting/cracking only affects the carb setups. But I don't want first-hand knowledge of that being incorrect. I suspect that I have been running with mine venting (cracked), without realizing it, for the last year.
Corbin
Corbin,
The bottle cap is a shitty design. Besides the cap cracking, the threads can also crack. With a carbureted engine, when that happens it introduces low pressure into your header tank and winds up having an engine that doesn't want to run too well and it first starts acting up at about three or four hundred feet after takeoff. Then you have to Mayday and see if you can limp around the pattern. If you're lucky you will have a passenger along who will later praise your excellent skills and nerves of steel.
I don't know what happens with a fuel injection engine but if it was me, I wouldn't want to investigate too far. There are a lot of different ways the guys have done fuel caps, not just the one that I use, but mine is pretty simple and you can get parts at any hardware store. There are more elegant methods out there, such as with the Vai-Ez guys may use.
Take care.
Sam I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
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Corbin N33QR
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Corbin N121CG
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Vented tab? You don't want a vent there. Better carry a spare. Fly Safe, Mike N3QP Q200
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Here's the set up on mine. Using a modified plumbing cap. There is a rubber seal at the top of the thread The inside of the filler neck has a vent tube in it that will go to the rest of the system, I haven't figured out what the original builder was intending but I think I might modify the cap by installing a vented tab into the slot.
Agreed. Honestly, I just want to get the conditional signed off before he has to leave town. My understanding is the venting/cracking only affects the carb setups. But I don't want first-hand knowledge of that being incorrect. I suspect that I have been running with mine venting (cracked), without realizing it, for the last year.
Corbin
Corbin,
The bottle cap is a shitty design. Besides the cap cracking, the threads can also crack. With a carbureted engine, when that happens it introduces low pressure into your header tank and winds up having an engine that doesn't want to run too well and it first starts acting up at about three or four hundred feet after takeoff. Then you have to Mayday and see if you can limp around the pattern. If you're lucky you will have a passenger along who will later praise your excellent skills and nerves of steel.
I don't know what happens with a fuel injection engine but if it was me, I wouldn't want to investigate too far. There are a lot of different ways the guys have done fuel caps, not just the one that I use, but mine is pretty simple and you can get parts at any hardware store. There are more elegant methods out there, such as with the Vai-Ez guys may use.
Take care.
Sam I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
  --
Corbin N33QR
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Corbin N121CG
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I re read your email. I also have a vent tube like that in my tank filter. The deal is that without it, and you've got the filter neck full of fuel. The incoming fuel pressurizes the tank until it finally burps and sprays fuel all over you. With the vent, the air comes out as the fuel goes in. I needed it because I have a water filter in the tank filler tube and I can easily fill the neck. Mike
toggle quoted messageShow quoted text
Here's the set up on mine. Using a modified plumbing cap. There is a rubber seal at the top of the thread The inside of the filler neck has a vent tube in it that will go to the rest of the system, I haven't figured out what the original builder was intending but I think I might modify the cap by installing a vented tab into the slot.
Agreed. Honestly, I just want to get the conditional signed off before he has to leave town. My understanding is the venting/cracking only affects the carb setups. But I don't want first-hand knowledge of that being incorrect. I suspect that I have been running with mine venting (cracked), without realizing it, for the last year.
Corbin
Corbin,
The bottle cap is a shitty design. Besides the cap cracking, the threads can also crack. With a carbureted engine, when that happens it introduces low pressure into your header tank and winds up having an engine that doesn't want to run too well and it first starts acting up at about three or four hundred feet after takeoff. Then you have to Mayday and see if you can limp around the pattern. If you're lucky you will have a passenger along who will later praise your excellent skills and nerves of steel.
I don't know what happens with a fuel injection engine but if it was me, I wouldn't want to investigate too far. There are a lot of different ways the guys have done fuel caps, not just the one that I use, but mine is pretty simple and you can get parts at any hardware store. There are more elegant methods out there, such as with the Vai-Ez guys may use.
Take care.
Sam I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
  --
Corbin N33QR
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Corbin N121CG
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It doesn't help that I used the wrong terminology...and probably still am... I meant ram air, not vent. I was thinking of pressurizing the system through the cap with a tube faired inside a blade like tab facing forward .
toggle quoted messageShow quoted text
On Mon, Mar 15, 2021, 10:43 PM Mike Dwyer, < q200pilot@...> wrote: I re read your email. I also have a vent tube like that in my tank filter. The deal is that without it, and you've got the filter neck full of fuel. The incoming fuel pressurizes the tank until it finally burps and sprays fuel all over you. With the vent, the air comes out as the fuel goes in. I needed it because I have a water filter in the tank filler tube and I can easily fill the neck. Mike
Here's the set up on mine. Using a modified plumbing cap. There is a rubber seal at the top of the thread The inside of the filler neck has a vent tube in it that will go to the rest of the system, I haven't figured out what the original builder was intending but I think I might modify the cap by installing a vented tab into the slot.
Agreed. Honestly, I just want to get the conditional signed off before he has to leave town. My understanding is the venting/cracking only affects the carb setups. But I don't want first-hand knowledge of that being incorrect. I suspect that I have been running with mine venting (cracked), without realizing it, for the last year.
Corbin
Corbin,
The bottle cap is a shitty design. Besides the cap cracking, the threads can also crack. With a carbureted engine, when that happens it introduces low pressure into your header tank and winds up having an engine that doesn't want to run too well and it first starts acting up at about three or four hundred feet after takeoff. Then you have to Mayday and see if you can limp around the pattern. If you're lucky you will have a passenger along who will later praise your excellent skills and nerves of steel.
I don't know what happens with a fuel injection engine but if it was me, I wouldn't want to investigate too far. There are a lot of different ways the guys have done fuel caps, not just the one that I use, but mine is pretty simple and you can get parts at any hardware store. There are more elegant methods out there, such as with the Vai-Ez guys may use.
Take care.
Sam I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
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Corbin N33QR
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Corbin N121CG
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Hi Mike. You'd likely have to stick the tube out at least 2" to get outside the boundary layer. It would be ugly in my opinion. Mike Dwyer
toggle quoted messageShow quoted text
It doesn't help that I used the wrong terminology...and probably still am... I meant ram air, not vent. I was thinking of pressurizing the system through the cap with a tube faired inside a blade like tab facing forward .
On Mon, Mar 15, 2021, 10:43 PM Mike Dwyer, < q200pilot@...> wrote: I re read your email. I also have a vent tube like that in my tank filter. The deal is that without it, and you've got the filter neck full of fuel. The incoming fuel pressurizes the tank until it finally burps and sprays fuel all over you. With the vent, the air comes out as the fuel goes in. I needed it because I have a water filter in the tank filler tube and I can easily fill the neck. Mike
Here's the set up on mine. Using a modified plumbing cap. There is a rubber seal at the top of the thread The inside of the filler neck has a vent tube in it that will go to the rest of the system, I haven't figured out what the original builder was intending but I think I might modify the cap by installing a vented tab into the slot.
Agreed. Honestly, I just want to get the conditional signed off before he has to leave town. My understanding is the venting/cracking only affects the carb setups. But I don't want first-hand knowledge of that being incorrect. I suspect that I have been running with mine venting (cracked), without realizing it, for the last year.
Corbin
Corbin,
The bottle cap is a shitty design. Besides the cap cracking, the threads can also crack. With a carbureted engine, when that happens it introduces low pressure into your header tank and winds up having an engine that doesn't want to run too well and it first starts acting up at about three or four hundred feet after takeoff. Then you have to Mayday and see if you can limp around the pattern. If you're lucky you will have a passenger along who will later praise your excellent skills and nerves of steel.
I don't know what happens with a fuel injection engine but if it was me, I wouldn't want to investigate too far. There are a lot of different ways the guys have done fuel caps, not just the one that I use, but mine is pretty simple and you can get parts at any hardware store. There are more elegant methods out there, such as with the Vai-Ez guys may use.
Take care.
Sam I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
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Corbin N33QR
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Corbin N121CG
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Hey Mike, You're probably right.These are my initial thoughts and being busy with the flight controls right now I haven't put a lot of thought into it. Where did you run yours, on the belly?
toggle quoted messageShow quoted text
On Tue, Mar 16, 2021 at 8:47 AM Mike Dwyer < q200pilot@...> wrote: Hi Mike. You'd likely have to stick the tube out at least 2" to get outside the boundary layer. It would be ugly in my opinion. Mike Dwyer
It doesn't help that I used the wrong terminology...and probably still am... I meant ram air, not vent. I was thinking of pressurizing the system through the cap with a tube faired inside a blade like tab facing forward .
On Mon, Mar 15, 2021, 10:43 PM Mike Dwyer, < q200pilot@...> wrote: I re read your email. I also have a vent tube like that in my tank filter. The deal is that without it, and you've got the filter neck full of fuel. The incoming fuel pressurizes the tank until it finally burps and sprays fuel all over you. With the vent, the air comes out as the fuel goes in. I needed it because I have a water filter in the tank filler tube and I can easily fill the neck. Mike
Here's the set up on mine. Using a modified plumbing cap. There is a rubber seal at the top of the thread The inside of the filler neck has a vent tube in it that will go to the rest of the system, I haven't figured out what the original builder was intending but I think I might modify the cap by installing a vented tab into the slot.
Agreed. Honestly, I just want to get the conditional signed off before he has to leave town. My understanding is the venting/cracking only affects the carb setups. But I don't want first-hand knowledge of that being incorrect. I suspect that I have been running with mine venting (cracked), without realizing it, for the last year.
Corbin
Corbin,
The bottle cap is a shitty design. Besides the cap cracking, the threads can also crack. With a carbureted engine, when that happens it introduces low pressure into your header tank and winds up having an engine that doesn't want to run too well and it first starts acting up at about three or four hundred feet after takeoff. Then you have to Mayday and see if you can limp around the pattern. If you're lucky you will have a passenger along who will later praise your excellent skills and nerves of steel.
I don't know what happens with a fuel injection engine but if it was me, I wouldn't want to investigate too far. There are a lot of different ways the guys have done fuel caps, not just the one that I use, but mine is pretty simple and you can get parts at any hardware store. There are more elegant methods out there, such as with the Vai-Ez guys may use.
Take care.
Sam I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
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Corbin N33QR
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Corbin N121CG
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I located the fuel vent on the bottom of the right side canard wing. It runs to the header tank. I got the measurement from the factory Q200. If you want the location I'll get it to you. Mike Dwyer
toggle quoted messageShow quoted text
Hey Mike, You're probably right.These are my initial thoughts and being busy with the flight controls right now I haven't put a lot of thought into it. Where did you run yours, on the belly?
On Tue, Mar 16, 2021 at 8:47 AM Mike Dwyer < q200pilot@...> wrote: Hi Mike. You'd likely have to stick the tube out at least 2" to get outside the boundary layer. It would be ugly in my opinion. Mike Dwyer
It doesn't help that I used the wrong terminology...and probably still am... I meant ram air, not vent. I was thinking of pressurizing the system through the cap with a tube faired inside a blade like tab facing forward .
On Mon, Mar 15, 2021, 10:43 PM Mike Dwyer, < q200pilot@...> wrote: I re read your email. I also have a vent tube like that in my tank filter. The deal is that without it, and you've got the filter neck full of fuel. The incoming fuel pressurizes the tank until it finally burps and sprays fuel all over you. With the vent, the air comes out as the fuel goes in. I needed it because I have a water filter in the tank filler tube and I can easily fill the neck. Mike
Here's the set up on mine. Using a modified plumbing cap. There is a rubber seal at the top of the thread The inside of the filler neck has a vent tube in it that will go to the rest of the system, I haven't figured out what the original builder was intending but I think I might modify the cap by installing a vented tab into the slot.
Agreed. Honestly, I just want to get the conditional signed off before he has to leave town. My understanding is the venting/cracking only affects the carb setups. But I don't want first-hand knowledge of that being incorrect. I suspect that I have been running with mine venting (cracked), without realizing it, for the last year.
Corbin
Corbin,
The bottle cap is a shitty design. Besides the cap cracking, the threads can also crack. With a carbureted engine, when that happens it introduces low pressure into your header tank and winds up having an engine that doesn't want to run too well and it first starts acting up at about three or four hundred feet after takeoff. Then you have to Mayday and see if you can limp around the pattern. If you're lucky you will have a passenger along who will later praise your excellent skills and nerves of steel.
I don't know what happens with a fuel injection engine but if it was me, I wouldn't want to investigate too far. There are a lot of different ways the guys have done fuel caps, not just the one that I use, but mine is pretty simple and you can get parts at any hardware store. There are more elegant methods out there, such as with the Vai-Ez guys may use.
Take care.
Sam I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
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Corbin N33QR
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Corbin N121CG
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Sure I'll take that...put it in my fuel file.
I've got to finish my elevator trim, the rudder pedals, canopy and brakes before I switch over to the fuel.
But any advice or photos would be most welcome!
toggle quoted messageShow quoted text
I located the fuel vent on the bottom of the right side canard wing. It runs to the header tank. I got the measurement from the factory Q200. If you want the location I'll get it to you. Mike Dwyer
Hey Mike, You're probably right.These are my initial thoughts and being busy with the flight controls right now I haven't put a lot of thought into it. Where did you run yours, on the belly?
On Tue, Mar 16, 2021 at 8:47 AM Mike Dwyer < q200pilot@...> wrote: Hi Mike. You'd likely have to stick the tube out at least 2" to get outside the boundary layer. It would be ugly in my opinion. Mike Dwyer
It doesn't help that I used the wrong terminology...and probably still am... I meant ram air, not vent. I was thinking of pressurizing the system through the cap with a tube faired inside a blade like tab facing forward .
On Mon, Mar 15, 2021, 10:43 PM Mike Dwyer, < q200pilot@...> wrote: I re read your email. I also have a vent tube like that in my tank filter. The deal is that without it, and you've got the filter neck full of fuel. The incoming fuel pressurizes the tank until it finally burps and sprays fuel all over you. With the vent, the air comes out as the fuel goes in. I needed it because I have a water filter in the tank filler tube and I can easily fill the neck. Mike
Here's the set up on mine. Using a modified plumbing cap. There is a rubber seal at the top of the thread The inside of the filler neck has a vent tube in it that will go to the rest of the system, I haven't figured out what the original builder was intending but I think I might modify the cap by installing a vented tab into the slot.
Agreed. Honestly, I just want to get the conditional signed off before he has to leave town. My understanding is the venting/cracking only affects the carb setups. But I don't want first-hand knowledge of that being incorrect. I suspect that I have been running with mine venting (cracked), without realizing it, for the last year.
Corbin
Corbin,
The bottle cap is a shitty design. Besides the cap cracking, the threads can also crack. With a carbureted engine, when that happens it introduces low pressure into your header tank and winds up having an engine that doesn't want to run too well and it first starts acting up at about three or four hundred feet after takeoff. Then you have to Mayday and see if you can limp around the pattern. If you're lucky you will have a passenger along who will later praise your excellent skills and nerves of steel.
I don't know what happens with a fuel injection engine but if it was me, I wouldn't want to investigate too far. There are a lot of different ways the guys have done fuel caps, not just the one that I use, but mine is pretty simple and you can get parts at any hardware store. There are more elegant methods out there, such as with the Vai-Ez guys may use.
Take care.
Sam I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
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Corbin N33QR
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Corbin N121CG
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britmcman99
I found a cap at my local tractor supply. That is a common cap.
toggle quoted messageShow quoted text
On Mar 15, 2021, at 1:55 PM, Mike Steinsland <MIKESKUSTOMS@...> wrote:
Looks like one off a 50 Gal food grade barrel My cap like this is tan/brown. I cracked one by over tightening it. Take the old cap and go see what it fits!
I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
<IMG_5968.jpeg> <IMG_5969.jpeg> --
Corbin N33QR
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Corbin
Ahh....there’s one close to the airport. Thanks! Corbin
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On Mar 16, 2021, at 11:19 AM, Phil Lankford via groups.io <britmcman@...> wrote:
I found a cap at my local tractor supply. That is a common cap.
Phil On Mar 15, 2021, at 1:55 PM, Mike Steinsland <MIKESKUSTOMS@...> wrote:
Looks like one off a 50 Gal food grade barrel My cap like this is tan/brown. I cracked one by over tightening it. Take the old cap and go see what it fits!
I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
<IMG_5968.jpeg> <IMG_5969.jpeg> --
Corbin N33QR
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Corbin N121CG
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Frankenbird Vern
They have an aviation parts department !! :-)
Lowes Aircraft supply.. Experimental Depot too.
Best part is most of my engine C.I. needs are located over at "Aircraft Zone" who share shelf space with the
local Auto Zone.
Gggg..
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From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Corbin via groups.io <c_geiser@...>
Sent: Tuesday, March 16, 2021 11:29 AM
To: main@q-list.groups.io <main@q-list.groups.io>
Subject: Re: [Q-List] Non-vented Fuel Cap Replacement
Ahh....there’s one close to the airport. Thanks!
Corbin
On Mar 16, 2021, at 11:19 AM, Phil Lankford via groups.io <britmcman@...> wrote:
I found a cap at my local tractor supply. That is a common cap.
Phil
On Mar 15, 2021, at 1:55 PM, Mike Steinsland <MIKESKUSTOMS@...> wrote:
Looks like one off a 50 Gal food grade barrel
My cap like this is tan/brown. I cracked one by over tightening it. Take the old cap and go see what it fits!
I haven't made Sam's modification using the PVC fitting yet so I am curious if anyone knows the source of this fuel cap that I have. My A&P found a crack in it during my conditional this week (ready to fly now).
<IMG_5968.jpeg>
<IMG_5969.jpeg>
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Corbin
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Corbin
N121CG
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David Cyr
The fuel filler is located in a low-pressure area, so you don't want any significant opening there. There was a suggestion to have a pin hole in the cap, but I never added that because of our similar power-loss experience. Early on, a line boy insisted on pumping the fuel and when he finished, he put the filler cap on cross thread. My building partner then tried to go flying. As he approached take-off speed, the engine faltered the same way Mike Dwyer described, so he aborted the take-off, stopped hard and stood the Q2 on its nose. The "pin hole" idea may be OK as long as the ram air volume coming into the header tank is sufficient to overcome the loss of air volume going out the hole in the cap caused by the low-pressure in the fuel filler area. I assume the low pressure is the result of the wing lift phenomenon on the top side of an airfoil.
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