Fuel Balancing

How to keep the Cessna 170 flying and airworthy.

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LRF
Posts: 15
Joined: Tue Jun 21, 2005 5:35 am

Fuel Balancing

Post by LRF »

I have reviewed the previous discussions on this, but haven't seen anyone with my problem I have a ragwing with the original tanks (2 right and 1 left) and a single gooseneck vent. I received my private license in Sept '05, bought this plane at that time and have put about 85 hrs on her since. I always, repeat always, fly on "both". The two sides rarely pull equally, but they are generally reasonably close. The guages are actually fairly representative.

On one occassion however, while on "both", I had the right tanks provide all the fuel while the left side provided none. I am verifying by strap - not by guage. After letting sit overnight, and still on "both", the left tank was still full - in other words they didn't equalize. I assumed I had a debris problem, but the problem switched in reverse (right tanks staying full) on a later trip. At this point I assumed, although with concern, that the fuel switch was sensitive to its exact positioning.

Everything went back to normal until the above actually happened a second time on a round trip. The left burned fuel out and right burned fuel back. I fueled up at my destination airport and intentionally never adjusted the fuel switch (which was on "both") to take that factor out of the equation. I had about a 25 - 35 mph quartering crosswind at altitude on that trip. Could that be a factor on venting? Doesn't explain the unequal tanks overnight though. Am I confused - shouldn't the tanks equalize.

Thank you for your help.
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cessna170bdriver
Posts: 4063
Joined: Mon Apr 22, 2002 5:13 pm

Re: Fuel Balancing

Post by cessna170bdriver »

LRF wrote:...I had about a 25 - 35 mph quartering crosswind at altitude on that trip. Could that be a factor on venting? Doesn't explain the unequal tanks overnight though.
I'm sorry I don't have any ideas about your tank problem, other than it isn't a crosswind while airborne. If you have the ball centered, the relative wind is parallel to the long axis of the airplane, regardless of what your track over the ground is.

Miles
Miles

“I envy no man that knows more than myself, but pity them that know less.”
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mrpibb
Posts: 395
Joined: Wed Apr 23, 2003 10:48 pm

Post by mrpibb »

As a owner of a ragwing, I came across the problem on long trips. and it was usually burned out of the left tank when I flew from jersey to NH and then the right on the return trip. The winds usually blow from the north west so I figured it was due to flight attitude. So what I do on trips now is burn from the right tank untill I'm about one hour from my destination then switch to both. As for fuel crossfeed when parked, It will not if parked level and your fuel is at 3/4 or below. you have to remember our fuel lines on the 48 are plumed differently then the later models, they run foward and enter at the foward door post/bulkhead area, so in a three point attitude the fuel line is at one point higher than the fuel level, That's why we have the fuel pump to prevent fuel starvation at prolonged high angles of attack and unusual attititudes (which kinda describes my flying :wink: ) .

see here http://sandhillaviation.com/fuelsys.pdf
Vic
N2609V
48 Ragwing
A Lanber 2097 12 gauge O/U Sporting
A happy go lucky Ruger Red label 20 ga
12N Aeroflex
Andover NJ
http://www.sandhillaviation.com
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" Air is free untill you have to move it" BB.
LRF
Posts: 15
Joined: Tue Jun 21, 2005 5:35 am

Post by LRF »

Thanks for the help...it all makes since. MRPIBB, do you have more than one vent for your tanks and is it a concern to you? That's a good looking plane by your picture. I notice you appear to have a little dihedral to your wings. Mine is the same way.
Larry Forney
1948 C-170 (ragwing)
N4046V
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GAHorn
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Joined: Fri Apr 12, 2002 8:45 pm

Post by GAHorn »

Hey, Larry!
Do you live at Arcola? Where do you keep your plane?
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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