air bubbles / fuel lines.....KILLIN' ME !!
04-16-2007 | 10:56 AM
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From: St Helens,
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air bubbles / fuel lines.....KILLIN' ME !!
Sheeeesh.......there has got to be a way to prevent air bubbles in the fuel lines on these smaller glow fuel motor's. I lost my showtime last summer due to the motor cutting out and dying right above a 100' oak tree and then again yesterday , i just barely saved my Funtana 100X. I'm running a saito 150 in the funtana , and also have one of the little saito 125's , and if you get down to close to a 1/4 or 1/3 tank and your doing some pretty harsh 3D type stuff , the clunk will suck an air bubble and kill the engine. All i did yesterday was tear the landing gear off nice and clean (easy fix) , but is there anything out there i can use that will help on preventing air bubbles getting into my lines? Or at least cut back on the amonut? I have the tank wrapped around with some 1/2" memory silicone memory foam , and the clunk is moving around pretty good ( fuel line is still pretty soft). I can only get about 7-8 minute flights , and anything more than that , i risk getting a bubble in the line. The 150 died on me at about 20' up yesterday in a hover , and barely had the speed to land it on the deadstick without wiping the plane out.
any advice?
any advice?
04-16-2007 | 01:23 PM
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RE: air bubbles / fuel lines.....KILLIN' ME !!
Get the correct clunk and this won't happen untill you run out of fuel. YS and OS both make these clunks.
http://www2.towerhobbies.com/cgi-bin...&I=LXXF25&P=ML
http://www2.towerhobbies.com/cgi-bin...&I=LXXF25&P=ML
04-16-2007 | 10:06 PM
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From: Puryear, TN
RE: air bubbles / fuel lines.....KILLIN' ME !!
Feed your main tank into a 2 oz. header tank. Muffler pressure goes to main tank vent, main tank clunk to header tank vent, header tank clunk to carb.......No air bubbles until you get down to 2 oz......Works great..... 
04-16-2007 | 10:09 PM
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RE: air bubbles / fuel lines.....KILLIN' ME !!
lot of added weight / uneccessarily complex setup to save $3 - $15?
Although I have seen it done on a couple of planes and it works well... more a heli thing though.
edit: I guess that doesnt really save any money now that I think about it.
Although I have seen it done on a couple of planes and it works well... more a heli thing though.
edit: I guess that doesnt really save any money now that I think about it.
04-16-2007 | 10:14 PM
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From: Puryear, TN
RE: air bubbles / fuel lines.....KILLIN' ME !!
ORIGINAL: sinergy
lot of added weight / uneccessarily complex setup to save $3 - $15?
lot of added weight / uneccessarily complex setup to save $3 - $15?
Just that it works. He might have a 2 oz tank laying around also....
04-16-2007 | 11:04 PM
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From: Auburn,
WA
RE: air bubbles / fuel lines.....KILLIN' ME !!
You could try one of these. [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXD741&P=7]Dubro[/link] It's actually listed as a filter but looks like it would separate the bubbles too. Cheap too.
04-17-2007 | 01:54 AM
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From: North, UNITED KINGDOM
RE: air bubbles / fuel lines.....KILLIN' ME !!
hi JEFF
none of my glow fuel motors suffer from bubbles in the fuel lines and will (if I let them) run fine untill the tanks are empty.
balance your prop, wrap your tank in a softer foam.
if you need a header tank for your engine to run properly there is something wrong with your set-up.
btw "little saito 125's " and "smaller glow fuel motor's",,,,,,,,,,,,,,,give me a break pal!!!!!!!!!!!
none of my glow fuel motors suffer from bubbles in the fuel lines and will (if I let them) run fine untill the tanks are empty.
balance your prop, wrap your tank in a softer foam.
if you need a header tank for your engine to run properly there is something wrong with your set-up.
btw "little saito 125's " and "smaller glow fuel motor's",,,,,,,,,,,,,,,give me a break pal!!!!!!!!!!!
04-17-2007 | 09:27 AM
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From: St Helens,
OR
RE: air bubbles / fuel lines.....KILLIN' ME !!
ORIGINAL: piroflip2
hi JEFF
none of my glow fuel motors suffer from bubbles in the fuel lines and will (if I let them) run fine untill the tanks are empty.
balance your prop, wrap your tank in a softer foam.
if you need a header tank for your engine to run properly there is something wrong with your set-up.
btw "little saito 125's " and "smaller glow fuel motor's",,,,,,,,,,,,,,,give me a break pal!!!!!!!!!!!
hi JEFF
none of my glow fuel motors suffer from bubbles in the fuel lines and will (if I let them) run fine untill the tanks are empty.
balance your prop, wrap your tank in a softer foam.
if you need a header tank for your engine to run properly there is something wrong with your set-up.
btw "little saito 125's " and "smaller glow fuel motor's",,,,,,,,,,,,,,,give me a break pal!!!!!!!!!!!
well............they are kind of small compared to what i've been flying anyways hehehe !!
I have a 35% WH sukoi coming and a BME 115 with a set of cans that are gettin' lonely and dying to be ran.
BUT......on the exceptionally large glow fuel motor's ( is that better ?
) i have a problem with them getting the air bubble only about every 7-8th flight....just enough to screw with my confindence that day. I'm going to look into those better clunks and also that little 2oz sub-tank a guy mentioned above....that's some good advice i can use.As far as the damage goes......besides my funtanna 100X , there are two guy with the same plane also. We really wring these little sucker's out , and with the throws set on 40-50 degree's , the little sucker will just about flip inside a 8' raduis , over and over , and over.......pretty sweet!! The damage.........it just tore off the landing gear and that was it. the other two guys have had the same thing happen when they came in on a pretty hard landing.
Get this.....The 2" X 5-1/4" X 3/8th thick block for the landing gear...popped out really clean. And just like the other two guys said , it's only put in with CA , not epoxy........or the epoxy was put on extremely light. I didn't even get any wood splinter's between the two block. The block was in perfect shape and still attached the the landing gear , with no damage to the airplane , except for where the wheel pants went through the covering.
The other 2 guys said their's did the exact same thing.......i asked them why the heck didn't they mention this before? I would have slapped on some epoxy and saved myself a headache.HAHA!! Oh well.....thanks for all your advice guys...i'm looking into both the clunk and the little sub-tank idea's today , get er' all set up and tear it up again next weekend ( <<< figure of speech ).
Jeff
04-17-2007 | 08:52 PM
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From: Weatherford,
TX
RE: air bubbles / fuel lines.....KILLIN' ME !!
If you are using a fuel with castor in it, the fuel will foam. Try a fuel with all synthetic and it will stop foaming.
04-18-2007 | 04:35 PM
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From: Salem ,
OR
RE: air bubbles / fuel lines.....KILLIN' ME !!
Jeff, I have come to realize that if that little block didn't pop out, then you'd probably rip that block, plus a former, or a firewall out with it, and have alot more damage. People scream and cry because they want light 3D planes (like me ) but when they have a less than perfect landing that pops out the gear, it is immediately blamed on the design of the plane. It is common practice, and knowledge, especially on the 30% and bigger planes, that if you know you're going to be rough on landings then you better strengthen up the stock gear supports. Look at the side notes that come with QQ, and Airwild planes.
Mike.
) but when they have a less than perfect landing that pops out the gear, it is immediately blamed on the design of the plane. It is common practice, and knowledge, especially on the 30% and bigger planes, that if you know you're going to be rough on landings then you better strengthen up the stock gear supports. Look at the side notes that come with QQ, and Airwild planes. Mike.
ORIGINAL: JEFFRO503
well............they are kind of small compared to what i've been flying anyways hehehe !!
I have a 35% WH sukoi coming and a BME 115 with a set of cans that are gettin' lonely and dying to be ran.
BUT......on the exceptionally large glow fuel motor's ( is that better ? ) i have a problem with them getting the air bubble only about every 7-8th flight....just enough to screw with my confindence that day. I'm going to look into those better clunks and also that little 2oz sub-tank a guy mentioned above....that's some good advice i can use.
As far as the damage goes......besides my funtanna 100X , there are two guy with the same plane also. We really wring these little sucker's out , and with the throws set on 40-50 degree's , the little sucker will just about flip inside a 8' raduis , over and over , and over.......pretty sweet!! The damage.........it just tore off the landing gear and that was it. the other two guys have had the same thing happen when they came in on a pretty hard landing.
Get this.....The 2" X 5-1/4" X 3/8th thick block for the landing gear...popped out really clean. And just like the other two guys said , it's only put in with CA , not epoxy........or the epoxy was put on extremely light. I didn't even get any wood splinter's between the two block. The block was in perfect shape and still attached the the landing gear , with no damage to the airplane , except for where the wheel pants went through the covering.
The other 2 guys said their's did the exact same thing.......i asked them why the heck didn't they mention this before? I would have slapped on some epoxy and saved myself a headache.HAHA!! Oh well.....thanks for all your advice guys...i'm looking into both the clunk and the little sub-tank idea's today , get er' all set up and tear it up again next weekend ( <<< figure of speech ).
Jeff
ORIGINAL: piroflip2
hi JEFF
none of my glow fuel motors suffer from bubbles in the fuel lines and will (if I let them) run fine untill the tanks are empty.
balance your prop, wrap your tank in a softer foam.
if you need a header tank for your engine to run properly there is something wrong with your set-up.
btw "little saito 125's " and "smaller glow fuel motor's",,,,,,,,,,,,,,,give me a break pal!!!!!!!!!!!
hi JEFF
none of my glow fuel motors suffer from bubbles in the fuel lines and will (if I let them) run fine untill the tanks are empty.
balance your prop, wrap your tank in a softer foam.
if you need a header tank for your engine to run properly there is something wrong with your set-up.
btw "little saito 125's " and "smaller glow fuel motor's",,,,,,,,,,,,,,,give me a break pal!!!!!!!!!!!
well............they are kind of small compared to what i've been flying anyways hehehe !!
I have a 35% WH sukoi coming and a BME 115 with a set of cans that are gettin' lonely and dying to be ran.
BUT......on the exceptionally large glow fuel motor's ( is that better ?
) i have a problem with them getting the air bubble only about every 7-8th flight....just enough to screw with my confindence that day. I'm going to look into those better clunks and also that little 2oz sub-tank a guy mentioned above....that's some good advice i can use.As far as the damage goes......besides my funtanna 100X , there are two guy with the same plane also. We really wring these little sucker's out , and with the throws set on 40-50 degree's , the little sucker will just about flip inside a 8' raduis , over and over , and over.......pretty sweet!! The damage.........it just tore off the landing gear and that was it. the other two guys have had the same thing happen when they came in on a pretty hard landing.
Get this.....The 2" X 5-1/4" X 3/8th thick block for the landing gear...popped out really clean. And just like the other two guys said , it's only put in with CA , not epoxy........or the epoxy was put on extremely light. I didn't even get any wood splinter's between the two block. The block was in perfect shape and still attached the the landing gear , with no damage to the airplane , except for where the wheel pants went through the covering.
The other 2 guys said their's did the exact same thing.......i asked them why the heck didn't they mention this before? I would have slapped on some epoxy and saved myself a headache.HAHA!! Oh well.....thanks for all your advice guys...i'm looking into both the clunk and the little sub-tank idea's today , get er' all set up and tear it up again next weekend ( <<< figure of speech ).
Jeff
04-19-2007 | 01:38 AM
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From: St Helens,
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RE: air bubbles / fuel lines.....KILLIN' ME !!
[quote]ORIGINAL: mtwister
Jeff, I have come to realize that if that little block didn't pop out, then you'd probably rip that block, plus a former, or a firewall out with it, and have alot more damage. People scream and cry because they want light 3D planes (like me
) but when they have a less than perfect landing that pops out the gear, it is immediately blamed on the design of the plane. It is common practice, and knowledge, especially on the 30% and bigger planes, that if you know you're going to be rough on landings then you better strengthen up the stock gear supports. Look at the side notes that come with QQ, and Airwild planes. I completely agree with that 100% In my case , hovering at a pretty close margin with the feild left me hardly no time to set up for a proper landing. If i would of been up about 5'-8' higher , i would of saved the landing gear and greased her in. And your also correct on the "keeping the planes light" and using hardly any epoxy or glue. I'm going to re-enforce the block a little , and just pray i don't get any more deadsticks that close to the ground. In fact......i'm doing my hovering a other wild crap at a little higher altitude until i know the motor is a little more stabe.
04-19-2007 | 02:44 PM
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From: Karachi, PAKISTAN
RE: air bubbles / fuel lines.....KILLIN' ME !!
ORIGINAL: WRM
If you are using a fuel with castor in it, the fuel will foam. Try a fuel with all synthetic and it will stop foaming.
If you are using a fuel with castor in it, the fuel will foam. Try a fuel with all synthetic and it will stop foaming.
