701 Fuel tanks -- uneven consumption - Zenith Aircraft Builders and Flyers2024-03-29T10:28:53Zhttps://zenith.aero/forum/topics/701-fuel-tanks-uneven?commentId=2606393%3AComment%3A557219&x=1&feed=yes&xn_auth=noEsten,
Does your aircraft lea…tag:zenith.aero,2017-03-16:2606393:Comment:5572192017-03-16T10:04:22.983ZJim and Amelia Isaacshttps://zenith.aero/profile/JimIsaacs
<p>Esten,</p>
<p>Does your aircraft leak only after you fly, or all the time? Is there an access panel for the fuel connections?</p>
<p>Esten,</p>
<p>Does your aircraft leak only after you fly, or all the time? Is there an access panel for the fuel connections?</p> I might add, that it's the ri…tag:zenith.aero,2017-03-14:2606393:Comment:5568992017-03-14T15:41:05.977ZEsten C. Dahlinhttps://zenith.aero/profile/EstenCDahlin
I might add, that it's the right wing, not that it really matters, but fuel is slowly coming out of the hole in the wing from which the fuel drain is installed. I suppose I'll have to pull the skin off above and below? Possible sending unit seal?
I might add, that it's the right wing, not that it really matters, but fuel is slowly coming out of the hole in the wing from which the fuel drain is installed. I suppose I'll have to pull the skin off above and below? Possible sending unit seal? I have a Ch701, and noticed a…tag:zenith.aero,2017-03-14:2606393:Comment:5568162017-03-14T15:31:06.886ZEsten C. Dahlinhttps://zenith.aero/profile/EstenCDahlin
I have a Ch701, and noticed a small fuel leak, coming from above the fuel inspection drain under the wing. Its above the drain itself, so just wondering where, typically, the leak would be coming from?
I have a Ch701, and noticed a small fuel leak, coming from above the fuel inspection drain under the wing. Its above the drain itself, so just wondering where, typically, the leak would be coming from? This seems to be a common pro…tag:zenith.aero,2009-05-16:2606393:Comment:226152009-05-16T11:47:36.313ZRobert Staceyhttps://zenith.aero/profile/RobertStacey
This seems to be a common problem with high wing aircraft. To avoid this, I was planning on running my lines to a 4 way valve with RIGHT, BOTH, LEFT and OFF positions.<br />
<br />
Normal operation would be on BOTH. If fuel consumption was uneven ,switching to the fuller tank would aleviate this problem. Besides giving me control of which tank to use, this arrangement would prevent air from being sucked into the system if one tank did go dry.<br />
<br />
As I am still a year away from finishing my 701 this is only my…
This seems to be a common problem with high wing aircraft. To avoid this, I was planning on running my lines to a 4 way valve with RIGHT, BOTH, LEFT and OFF positions.<br />
<br />
Normal operation would be on BOTH. If fuel consumption was uneven ,switching to the fuller tank would aleviate this problem. Besides giving me control of which tank to use, this arrangement would prevent air from being sucked into the system if one tank did go dry.<br />
<br />
As I am still a year away from finishing my 701 this is only my opinion.<br />
<br />
Bob in Newfoundland. OK thanks, Ernest. Appreciate…tag:zenith.aero,2009-05-15:2606393:Comment:225682009-05-15T17:19:53.825ZRolf Grandstaffhttps://zenith.aero/profile/RolfGrandstaff
OK thanks, Ernest. Appreciate the info. Yeah, flaps on this airplane makes it drop like a stone.
OK thanks, Ernest. Appreciate the info. Yeah, flaps on this airplane makes it drop like a stone. Rolf,
I prefer no flaps. I ha…tag:zenith.aero,2009-05-15:2606393:Comment:225622009-05-15T16:15:41.995ZErnest Jesseehttps://zenith.aero/profile/ErnestJessee
Rolf,<br />
I prefer no flaps. I have landed with flaps and no throttle, but it seems like the elevator is a bit less responsive at touchdown and the angle of descent can become absurd. Bouncing is more likely also as lift is increased.<br />
<br />
So.. no flap and I set trim to neutral before I begin descent.
Rolf,<br />
I prefer no flaps. I have landed with flaps and no throttle, but it seems like the elevator is a bit less responsive at touchdown and the angle of descent can become absurd. Bouncing is more likely also as lift is increased.<br />
<br />
So.. no flap and I set trim to neutral before I begin descent. Ernest, I meant to ask you, w…tag:zenith.aero,2009-05-15:2606393:Comment:225602009-05-15T15:49:20.615ZRolf Grandstaffhttps://zenith.aero/profile/RolfGrandstaff
Ernest, I meant to ask you, when you do your power off landing at 60 mph, what configuration do you use for flaps and trim, if any? Thanks.<br />
<br />
Hope you have a great flight up to Franklin county!<br />
<br />
-Rolf
Ernest, I meant to ask you, when you do your power off landing at 60 mph, what configuration do you use for flaps and trim, if any? Thanks.<br />
<br />
Hope you have a great flight up to Franklin county!<br />
<br />
-Rolf Earnest,
Apart from uneven f…tag:zenith.aero,2009-05-15:2606393:Comment:225222009-05-15T02:58:23.636ZChumphol Sirinavinhttps://zenith.aero/profile/ChumpholSirinavin
Earnest,<br />
<br />
Apart from uneven fuel consumption in wing tanks that many have made comments, fuel fume, if not from known spill or overflow, needs a thorough installation check, with wing skin opening.<br />
<br />
Good fuel hose does not allow fuel to seep through. Good fuel hose with good retaining strap and good installation has no fuel leak. Cracks on hose end, due to rough cut, bad installation, or over age, allow fuel to leak. A friend of mine uses aluminum fuel line inside wings so he does not need to…
Earnest,<br />
<br />
Apart from uneven fuel consumption in wing tanks that many have made comments, fuel fume, if not from known spill or overflow, needs a thorough installation check, with wing skin opening.<br />
<br />
Good fuel hose does not allow fuel to seep through. Good fuel hose with good retaining strap and good installation has no fuel leak. Cracks on hose end, due to rough cut, bad installation, or over age, allow fuel to leak. A friend of mine uses aluminum fuel line inside wings so he does not need to replace the hidden rubber hoses every 5 years.<br />
<br />
A 701 built in 1996 that I bought has very simple fuel system. 4 small wing tank, 2 in each, have common low connection point before engine. The 4 tanks uses flush vent fuel caps (available at Wicks Aircraft), with no fuel selector, no tank strainer, no tank drain. Fresh fuel trace under wing forced me to open the wings and found bad connections. One wing had an old rubber hose, probably left unchanged and cracking up on one end. Another had a plastic zip lock in place of steel retainer strap. I have not made long enough flight to note any uneven consumption. Float type indicator have not shown much difference between wings. I am glad I have found bad connections. If there is any other problem, I have to find out on next flight later this year.<br />
<br />
Champ My 801 does the EXACT same th…tag:zenith.aero,2009-05-15:2606393:Comment:224962009-05-15T00:53:19.804ZBen Haashttps://zenith.aero/profile/Ben
My 801 does the EXACT same thing. Right down to the right wing did spill fuel and the left one didn't. I switched the fuel caps and nothing changed. Since I did a custom dual tank install I added additional tank venting that exits below the wing, I epoxied up the vent holes in the stock zenith caps and that stopped the spilling. Altho it happened on my very first flight and that one event stained my Dupont Imron paint... So much for aircraft paint holding up to 100LL blue dye.. Don't get me…
My 801 does the EXACT same thing. Right down to the right wing did spill fuel and the left one didn't. I switched the fuel caps and nothing changed. Since I did a custom dual tank install I added additional tank venting that exits below the wing, I epoxied up the vent holes in the stock zenith caps and that stopped the spilling. Altho it happened on my very first flight and that one event stained my Dupont Imron paint... So much for aircraft paint holding up to 100LL blue dye.. Don't get me started.... As for the uneven fuel. It has been thought over a lot. Common deduction is the prop wash spirals around the fuselage, hitting the bottom of the left wing and the top of the right wing. That uneven airflow " might" contribute to the quirk.<br />
Other then that I LOVE my 801. !!!!!<br />
<br />
Ben.<br />
N801BH. Earnest,
I've noticed the sa…tag:zenith.aero,2009-05-15:2606393:Comment:224942009-05-15T00:47:02.863ZTommy Walkerhttps://zenith.aero/profile/TommyWalker
Earnest,<br />
<br />
I've noticed the same thing, only in my case, the fuel burns faster from the right tank than the left!<br />
<br />
Some builders have added a positive vent tube to the caps to help pressurize the tanks. The tube is periscope shaped and faces the oncoming air.<br />
<br />
Do you have these type caps?<br />
<br />
The procedure for creating the vent tubes can be found on the Matronics Zenith List. Basically, you drill a hole in the cap and solder/weld the tube in place. You also have to solder/weld the two vent points…
Earnest,<br />
<br />
I've noticed the same thing, only in my case, the fuel burns faster from the right tank than the left!<br />
<br />
Some builders have added a positive vent tube to the caps to help pressurize the tanks. The tube is periscope shaped and faces the oncoming air.<br />
<br />
Do you have these type caps?<br />
<br />
The procedure for creating the vent tubes can be found on the Matronics Zenith List. Basically, you drill a hole in the cap and solder/weld the tube in place. You also have to solder/weld the two vent points inside the cap. Take a look at some of the pictures of 701's on the Zenith website and you will see an example.<br />
<br />
If you need more info, email me at twalker(at)cableone.net<br />
<br />
Tommy