Building a scale 1/4 scale Super Cub from Balsa J3 kit
02-24-2015, 07:23 AM
#927
Join Date: Sep 2006
Location: The Sunshine state, when it's not raining!
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Thats interesting bird, the one that was originally in my sig 1/4 cub was 4 years old with no problems... don't get me wrong, it was a concern but I never experienced any leakage, I always checked to make sure the pintel was seated, and never an issue in those 4 years... even after I converted the 130 to CDI, I still ran it on Glow fuel and used the same fueler
The Fuel valve you see in the above image, was the Great Planes "Easy Fill" valve.
Anyways I wouldn't want to steer Leroy wrong, so by all means thoroughly test it, or go with the fuel dot.
***EDIT***
This is the fuel dot I have now, made from a PL-259 coax connector.. but its the traditional J3 nose tank configuration, the super cub had wing tanks, but you could discreetly hide the fuel dot within the cowl area.
***EDIT***EDIT***
Just out of curiosity I dug out the original GP Easy Fill valve I had... its well over 15 years old and the seal is still intact... it seals, and holds a vacuum when both lines are plugged.... much greater vacuum than would be developed while the engine is running, or even with an exhaust pressure fitting back to the tank.
John M,
The Fuel valve you see in the above image, was the Great Planes "Easy Fill" valve.
Anyways I wouldn't want to steer Leroy wrong, so by all means thoroughly test it, or go with the fuel dot.
***EDIT***
This is the fuel dot I have now, made from a PL-259 coax connector.. but its the traditional J3 nose tank configuration, the super cub had wing tanks, but you could discreetly hide the fuel dot within the cowl area.
***EDIT***EDIT***
Just out of curiosity I dug out the original GP Easy Fill valve I had... its well over 15 years old and the seal is still intact... it seals, and holds a vacuum when both lines are plugged.... much greater vacuum than would be developed while the engine is running, or even with an exhaust pressure fitting back to the tank.
John M,
02-24-2015, 07:33 AM
#928
My Feedback: (6)
Pilotbum, Leroy. Bigbird3, Jhom_m
I did not mean to start a brew ha ha, or distract from Leroy's build thread. So I will add a bit , way back when I first started using gas engines, I had all kinds pf problems and found that 99% of it was due to the gas, ie pump gas, and the ethanol. So My buddy and I switched to ave/gass 100 and yes it is 4 to 6 a gallon depending on witch airport you go to get it. after that we just watched the fuel barbs for berrs or sharp edges. The other advantage of ave/gass is it does not smell or soure if you leave it in your field can over the winter.
That said, We all have to use what we are comfortable, and works for us. Have I ever had a bad experience with a product YES, due I try it again generally it depends on coast.
Sorry about the rant
Cheers Bob T
AMA13377
Corsair Brotherhood #6
I did not mean to start a brew ha ha, or distract from Leroy's build thread. So I will add a bit , way back when I first started using gas engines, I had all kinds pf problems and found that 99% of it was due to the gas, ie pump gas, and the ethanol. So My buddy and I switched to ave/gass 100 and yes it is 4 to 6 a gallon depending on witch airport you go to get it. after that we just watched the fuel barbs for berrs or sharp edges. The other advantage of ave/gass is it does not smell or soure if you leave it in your field can over the winter.
That said, We all have to use what we are comfortable, and works for us. Have I ever had a bad experience with a product YES, due I try it again generally it depends on coast.
Sorry about the rant
Cheers Bob T
AMA13377
Corsair Brotherhood #6
02-24-2015, 09:11 AM
#930
Thread Starter
Pilotbum, Leroy. Bigbird3, Jhom_m
I did not mean to start a brew ha ha, or distract from Leroy's build thread. So I will add a bit , way back when I first started using gas engines, I had all kinds pf problems and found that 99% of it was due to the gas, ie pump gas, and the ethanol. So My buddy and I switched to ave/gass 100 and yes it is 4 to 6 a gallon depending on witch airport you go to get it. after that we just watched the fuel barbs for berrs or sharp edges. The other advantage of ave/gass is it does not smell or soure if you leave it in your field can over the winter.
That said, We all have to use what we are comfortable, and works for us. Have I ever had a bad experience with a product YES, due I try it again generally it depends on coast.
Sorry about the rant
Cheers Bob T
AMA13377
Corsair Brotherhood #6
I did not mean to start a brew ha ha, or distract from Leroy's build thread. So I will add a bit , way back when I first started using gas engines, I had all kinds pf problems and found that 99% of it was due to the gas, ie pump gas, and the ethanol. So My buddy and I switched to ave/gass 100 and yes it is 4 to 6 a gallon depending on witch airport you go to get it. after that we just watched the fuel barbs for berrs or sharp edges. The other advantage of ave/gass is it does not smell or soure if you leave it in your field can over the winter.
That said, We all have to use what we are comfortable, and works for us. Have I ever had a bad experience with a product YES, due I try it again generally it depends on coast.
Sorry about the rant
Cheers Bob T
AMA13377
Corsair Brotherhood #6
Thanks for your input, that's part of why we are here, Leroy
02-24-2015, 10:10 AM
#931
Anything mechanical can fail sometimes it just comes down to luck of the draw. I wonder if there is a collation between the location, orientation, and how it is mounted to whether you have leaks or not with a fueler? "O" ring materials do vary from manufacturer to manufacturer as well as where and when they were made. I still like to hear about a product I use that someone else has had some bad luck using. Its a great way of learning what to look for if/when you do have a problem. When it comes to building we all build to suit ourselves but if we weren't interested in how others do something we wouldn't be here!
02-24-2015, 10:44 AM
#932
Great Planes Easy Fill
John M,
02-24-2015, 11:49 AM
#933
I just peeked and DuBro # 334 is the Fueler rebuilding kit for glow. The rebuilding kit for gasoline is DuBro # 335. Both can be used to covert an existing value to use whichever fuel type is desired, glow to gas or gas to glow. The picture below shows the parts Tower prices both kits at $4.09 about the same as my LHS.
Mike
Mike
02-24-2015, 12:15 PM
#934
My Feedback: (6)
Mike
The pic would not open, but your written description is correct, and when I check my birds out for the next spring flying season I all ways take the fuel line off at the carb and use a Robart air pump with a gage and put a little pressure into the system and look for leaks and pressure drop, vary easy to do, and save a lot of head ache's at the field
And I do keep a kit available in my shop, the repair is easy to do.
Cheers bob T
The pic would not open, but your written description is correct, and when I check my birds out for the next spring flying season I all ways take the fuel line off at the carb and use a Robart air pump with a gage and put a little pressure into the system and look for leaks and pressure drop, vary easy to do, and save a lot of head ache's at the field
And I do keep a kit available in my shop, the repair is easy to do.
Cheers bob T
02-24-2015, 12:18 PM
#935
Mike
The pic would not open, but your written description is correct, and when I check my birds out for the next spring flying season I all ways take the fuel line off at the carb and use a Robart air pump with a gage and put a little pressure into the system and look for leaks and pressure drop, vary easy to do, and save a lot of head ache's at the field
And I do keep a kit available in my shop, the repair is easy to do.
Cheers bob T
The pic would not open, but your written description is correct, and when I check my birds out for the next spring flying season I all ways take the fuel line off at the carb and use a Robart air pump with a gage and put a little pressure into the system and look for leaks and pressure drop, vary easy to do, and save a lot of head ache's at the field
And I do keep a kit available in my shop, the repair is easy to do.
Cheers bob T
02-24-2015, 12:22 PM
#936
Join Date: May 2003
Location: Denver, CO
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So this is exactly my point... rebuild kits, some fail, some don't, keeping spare parts and rebuild kits for when they do fail. It all seems like a lot of maintenance for something that can all be solved by using a fuel dot instead. So, what am I missing? Why use them? I'm sure its largely personal preference and all this is why my preference is the dot. Now I'm curious what y'all feel the advantages of these type filler valves are? I know we're beating a horse to death, but my curiosity is killing me...
02-24-2015, 12:38 PM
#939
Join Date: May 2003
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The valve on the bottom prevents any negative/positive pressure to the carb while fueling/de-fueling, right? That's why I just install a second clunk strictly for fueling/de-fueling.
02-24-2015, 02:24 PM
#943
So this is exactly my point... rebuild kits, some fail, some don't, keeping spare parts and rebuild kits for when they do fail. It all seems like a lot of maintenance for something that can all be solved by using a fuel dot instead. So, what am I missing? Why use them? I'm sure its largely personal preference and all this is why my preference is the dot. Now I'm curious what y'all feel the advantages of these type filler valves are? I know we're beating a horse to death, but my curiosity is killing me...
... trust me, if I had issues with the fuel filler valves, I would have chucked it in the trash years ago... but you also have to take into consideration how often they were used... I would get maybe 3-4 flights on one day out of a weekend, so it wasn't used excessively.John M,
Last edited by John_M_; 02-24-2015 at 03:45 PM.
02-24-2015, 02:26 PM
#944
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Thats interesting bird, the one that was originally in my sig 1/4 cub was 4 years old with no problems... don't get me wrong, it was a concern but I never experienced any leakage, I always checked to make sure the pintel was seated, and never an issue in those 4 years... even after I converted the 130 to CDI, I still ran it on Glow fuel and used the same fueler
The Fuel valve you see in the above image, was the Great Planes "Easy Fill" valve.
Anyways I wouldn't want to steer Leroy wrong, so by all means thoroughly test it, or go with the fuel dot.
John M,
The Fuel valve you see in the above image, was the Great Planes "Easy Fill" valve.
Anyways I wouldn't want to steer Leroy wrong, so by all means thoroughly test it, or go with the fuel dot.
John M,
Perhaps mine is an isolated case but most of my problems were when I disconnected the probe, the pintel stuck crossways and was difficult to reset. It never recovered and I finally went to the black plastic one mentioned in this discussion. But, if you want to simplify it, use the fuel dot! No moving parts!!!!
bird.
02-24-2015, 03:36 PM
#945
Thread Starter
Thank you John_m_ and FlyerinOKC for posting the inners of this little valve and the available repair kit, it's easy to see it's just a manually operated shuttle valve who's biggest enemy is dirt and lack of lube, a cover or cap would be a good Idea and I'm sticking with it. It's a good fit for what I did and solves a plumbing issue with it's use and gets it where I wanted it. Servicing it is no problem for me, I have every seal pick on the planet and have worked on a lot smaller valves than this one. I will get a kit in the event I ever need one
This is good stuff to know and it's nice to see guys come together the way you did with this one, I sure appreciate it and learned something else I didn't know.
Leroy
This is good stuff to know and it's nice to see guys come together the way you did with this one, I sure appreciate it and learned something else I didn't know.
Leroy
02-24-2015, 04:46 PM
#946
My Feedback: (31)
Join Date: Jan 2005
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Leroy, I hate to say it, but the fuel filler forward of the windshield,(ala J-3) would be very non-scale. On the Pa-18 Super Cub, the fwd.fuse. support cluster, goes right where fuel tank is on the Piper J-3. I waded thru hundreds of photo's on Airliners.Net and they all had fuel tanks mounted in the wings. i faked the fuel tank covers and filler caps recently, on a PA-22 (Tri-Pacer) that I completed recently.They are similar to the PA-18. I'll post or email pics, if interested.
I've used the fuel quick-fills,over the years, and they always ended up leaking fuel, or sucking air - due to o-rings or crap, under the valve seat.now i just go with a fuel fill line, out the bottom of the cowl - close to the wirewall. Cap it with a removable plug (fuel dot style) I leave extra line, so it can be pulled away from the belly for easy access. No leakage,spillage or valve maintenance. You can only have problems, if you forget to put the plug back in. John R.
I've used the fuel quick-fills,over the years, and they always ended up leaking fuel, or sucking air - due to o-rings or crap, under the valve seat.now i just go with a fuel fill line, out the bottom of the cowl - close to the wirewall. Cap it with a removable plug (fuel dot style) I leave extra line, so it can be pulled away from the belly for easy access. No leakage,spillage or valve maintenance. You can only have problems, if you forget to put the plug back in. John R.
02-24-2015, 05:22 PM
#947
Perhaps mine is an isolated case but most of my problems were when I disconnected the probe, the pintel stuck crossways and was difficult to reset. It never recovered and I finally went to the black plastic one mentioned in this discussion. But, if you want to simplify it, use the fuel dot! No moving parts!!!!
bird.
bird.
A little observation on my part... it may suggest that the Dubro brand may have an issue with the pintel cocking when pushed in with the fueler nipple... if you notice in the rebuild kit photo, the spring is larger in diameter at the bottom than it is at the top... that could allow the pintle to cock and the small end get trapped at an angle between the two O-ring seals.... on the Great Planes version the spring is straight, and does not allow the pintle to tip to one side.. that maybe why I went with the GP Easy Fueler, its been a long time since, and can't recall
John M,
02-24-2015, 08:39 PM
#949
Well here's another bit of revelation if you will... Duro makes a larger version of their Kiwk Fueler valves for large scale aircraft... the rebuild kits for those show a straight spring rather than the cone shaped spring... they are much larger than their STD size fuel valves, I'm mean they fill the palm of your hand, they are quite big... I wonder if they may have seen something in their original design that needed refinement.
Dubro Large Scale Fuel Valve Rebuild Kits
John M,
Dubro Large Scale Fuel Valve Rebuild Kits
John M,
02-25-2015, 08:58 AM
#950
Thread Starter
Well the more I hear about this whole affair the less I like it, I think I need to find out if gas can be pumped through the carburetor diaphragm when filling the tank flooding the engine especially an inverted engine, I think that was the main reason for that fill valve. If I go with a separate fill line I'm going to be pressurizing the first tank in order to force gas into the second tank and at this point I don't know if that's enough pressure to flood my engine. I may have opened up my own can of worms. I have to admit that one speck of dirt can cause plenty of trouble aside from it not belonging where I put it.
Right now it's all set up on the engine run stand the same way it is in the plane so I can test the whole system I just need to dress up the reed box first. More to come.
Leroy
Right now it's all set up on the engine run stand the same way it is in the plane so I can test the whole system I just need to dress up the reed box first. More to come.
Leroy