Champ fuel gauge very inaccurate?

[CptKelly]

Is there anything that can be done about a Champ's fuel gauge being very inaccurate? Normally, ours reads about half a tank low. Full, the tank gauge reads between a half and 3/4 of a tank. Are any parts available for this gauge unit?

Thanks,

Mike and Gail

[BobK]

Ive been thinking the same thing... Not to hijack the thread, but Ive been having opposite symptoms. My gauge shows higher than actual readings.

On a recent trip, I knew I should've been getting low on fuel, but was still showing almost 1/2 tank. When I landed, I had less than 5 gals available....

Ive always been skeptical of the gauge, being that I have the 13 gallon wing tanks, and a 2.5 gallon header tank, and the only fuel gauge I have is located in the right wing root. It looks to be the same design as the original Aeronca gauge that was mounted in the dash. Supposedly with the cross-feeding it "should" read correctly, but I never trust it. It always shows full when I fill up, but after that, its a guessing game.

I mostly use time-flown as a gauge for how much fuel I have left, and getting up around 4+ hours, I start getting nervous. Ive seen a couple different setups that I would like to try, but Im sure they are big $$$.

One had a fuel gauge stuck in each wing root. The other setup had sight-gauges like most Supercubs do. I think I liked that one the best. No gauge to trust, just the actual fuel in the tube showing you what you had left.

Im sure I'd be well over a couple thousand bucks trying to install sight glasses... Thats a couple thousand bucks better spent on fuel !

Hasta ~

Bob K.
Anchorage, AK

[joea]

Sedans use the clear plastic tubing that shows the actual level in the tanks. Given the choice that is what I would use, and still do what Bob does and time my flight and figure out 4.5 gallons an hour.

[Mnflyer]

[Robert Henley]

Is there anything that can be done about a Champ's fuel gauge being very inaccurate? Normally, ours reads about half a tank low. Full, the tank gauge reads between a half and 3/4 of a tank. Are any parts available for this gauge unit?

Thanks,

Mike and Gail

Mike

check this thread out:

http://joea.com/phpBB2/viewtopic.php?t=288

Regards

Robert

[jc pacquin]

i personally use a wooden paint stir stick from paint store. i mark it at full, half etc . Have used this hi tech method since almost running mooney out of gas, fat dumb and happy years ago.

[MikeB]

Agree with JC. I've always used a paint stick and marked it off once while filling the tank. Pretty fool proof and it's hard to judge how much fuel you have in a 13 gallon tank once it's down a few gallons. Also keep track of my time and use 4.5 gallons per hour (two hours would be my limit taking the pucker factor into consideration). My gauge is pretty accurate but bounces around so much it's hard to read in rough air.

Mike Berg

[t7275tr]

Never fear. Your fuel guage can be calibrated. Parts are readily available from any Ford Model A parts supplier. A complete new guage assembly with sight glass and gaskets is less than $40.

I would recommend getting the special wrench for tightening the large nut that holds the guage in place. You will probably have to bend the rod to calibrate the guage. Start with the tank empty and make sure the guage reads empty. Then put 3 gallons in the tank, check the reading. Take the guage out and bend the rod to get the correct reading.

I have mine set to read correctly when full and reads empty with 3 gallons in the tank. Remember to do the calibration with the tail raised to level flight attitude. I also have a dowel rod with calibration marks in 2 gallon increments. I stick the tank before flight and know exactly how much fuel I have.

[BobK]

I try to rely more on timing than the dipstick method. Because I have no valves to shut off the flow of fuel between the wing tanks and the header tank, I have no way of knowing how much fuel is transferring between them.

So, even if I completely drained the fuel from all tanks, and started adding 3 gallons to one wing tank, it would immediately drain into the header tank, and give me a false reading on the stick. Likewise, I would imagine that even once the header tank was full, any added fuel would try and balance out with the other wing tank. I haven't proved this for myself yet, but the previous owner said that if you filled up just one wing tank, it would balance out between the 2 tanks in a few hours.

Ive chalked this up to just one of the little nuances of my Champ that Im going to live with. No way am I going to dump gobs of money into installing sight gauges in both tanks. Thats money that is better used putting the fuel into the tanks !

Hasta ~

Bob K.
Anchorage, AK

[pablo]

The only time you know how much fuel you have is when you top it off yourself! From then on, go by elapsed tach time and do not fly a 7AC more than 2hrs (13gals tank) Remember that the regulations for fuel gauges establish that the only accuracy needed to be legal is for the gauges to show empty.
Pablo

[NC83401]

how much fuel is considered usable out of 13gal tank for a 7ac

[Nathan K. Hammond]

All of it.

nkh

[stknrdr]

I think the USAF flight manual for the L-16A says 12 usable. I assume the 13 gal boot tank did not change from the 7AC to the 7BCM.

I'm conservative and flight plan for 12 usable.

Tim

[Tugaske2]

In addition to the regular fuel guage on the nose fuselage tank..I have on both my Champs also a second piper type guage aka a wire with a cork float on the bottom extending through the top of the gas cap...one can paint colored marks on it for quantities...very accurate and a good backup..can be made easily..thought I would share this with you..

[joea]

Some of the fuselage tanks have a "domed" field modification to them. Know of many who have taken a broom handle or the like and working through the fuel filler port, you gently tap around the base of the fuel tank drain area to create a small sump. this way about 99% of the fuel goes out of the tank and into the fuel line to the carb.

Believe that there is a Aeronca modification that requires this being done but I forget which one it is.