Question

Please advise how to access the fuel tank sending unit on a 1956 Citroën Traction 11BL. Either I have lost the electrical connection or the ground, or maybe the float has sunk to the bottom of the tank. I have toyed with the assumption that since I have filled the tank with gasoline, the meter which is calibrated in liters of essence does not recognize the liquid which now fills the tank and therefore the gauge reads empty. Any and all advice sincerely appreciated.

Citroën Tech Tip

Thanks for your note. On a 6 volt system you always want to look for the ground to be the usual problem when something electrical does not work.

The sending unit operates by resistance in a coil of wire that the connection in the tank slides up and down on. When the tank is low with fuel, the connection is at the bottom of the coil with many windings. The higher the float goes in the tank, the fewer windings on the coil and thus the less resistance electrically. This makes your gauge on your dash head toward full. It starts off at about 1.5 volts and raises to the full 6 volts when the float is to the top and the tank is full.

If you have an electrical tester you want to gain access to the connections to the sending unit. This will be on the floor of your trunk under the floor mat. There should be a little trap door to gain access to the unit on the trunk floor.You will need a volt meter

of some kind, and a jumper wire preferably with an alligator clip on each end.

Disconnect the coil wire on the car, so that no damage happens to the ignition points, and then flip on the ignition key. Find the wire that is feeding power to your sender by touching the negative on the tester to a good grounding surface of bare metal in the trunk area. Then hook the positive end of the tester to one of the electrical wire ends leading to the sender. Once you find the positive connection you now know that you are at least getting current back to the sending unit.

Now make sure the connections are clean on the sender unit, and hook the jumper wire I mentioned that you needed to the other tab or screw connection on the sending unit. Clip the other end of the jumper wire to a good ground and then go see if your fuel gauge is working.

This is what I have found, over the years, to be the most common cause with Citroen Tractions and early Citroen D Series cars with 6 volt systems… A bad ground.

If that does not solve your problem, what I have found in rare cases is the cork fuel sender float in the tank has become water logged (or in this case fuel logged). Sometimes the new reformulated fuel can cause this to happen.

If that is the case you will need to remove the sending unit from the tank, and either replace it or find some type of coating to apply to the float that will stand up to fuel and seal the float.

Oh yes, and the next time you want to run your car, don’t forget to re-connect the coil wire.

.

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Recently Citroen Club of North America member Randall Jones sent in this
interesting list of tool definitions. Most of us who have worked on Citroën
cars can identify with it. Enjoy!
========================================================

DRILL PRESS: A tall upright machine useful for suddenly snatching flat
metal bar stock out of your hands so that it smacks you in the chest and
flings your soda across the room, splattering it against that freshly-stained
heirloom piece you were drying.

WIRE WHEEL: Cleans paint off bolts and then throws them somewhere under
the workbench with the speed of light. Also removes fingerprints and
hard-earned guitar callouses from fingers in about the time it takes you to say,
‘Yeouw….’

ELECTRIC HAND DRILL: Normally used for spinning pop rivets in their
holes until you die of old age, or for perforating something behind and beyond
the original intended target object.

SKIL SAW: A portable cutting tool used to make studs too short.

PLIERS: Used to round off bolt heads. Sometimes used in the creation of
blood-blisters.

BELT SANDER: An electric sanding tool commonly used to convert minor
touch-up jobs into major refinishing jobs. Caution: Avoid using for manicures.

HACKSAW: One of a family of cutting tools built for frustration enhancement.
It transforms human energy into a crooked, unpredictable motion, and the
more you attempt to influence its course, the more dismal your
future becomes.

VISE-GRIPS: Generally used after pliers to completely round off bolt
heads. If nothing else is available, they can also be used to transfer
intense welding heat to the palm of your hand.

WELDING GLOVES: Heavy duty leather gloves used to prolong the
conduction of intense welding heat to the palm of your hand.

OXYACETYLENE TORCH: Used almost entirely for lighting various flammable
objects in your shop on fire. Also handy for igniting the grease inside
the wheel hub you want the bearing race out of.

WHITWORTH SOCKETS: Once used for working on older British cars and
motorcycles, they are now used mainly for impersonating that 9/16 or
1/2 socket you’ve been searching for the last 45 minutes.

TABLE SAW: A large stationary power tool commonly used to launch wood
projectiles for testing wall integrity.

HYDRAULIC FLOOR JACK: Used for lowering an automobile to the ground
after you have installed your new brake shoes, trapping the jack handle
firmly under the bumper.

EIGHT-FOOT LONG YELLOW PINE 4X4: Used for levering an automobile upward
off of a trapped hydraulic jack handle.

TWEEZERS: A tool for removing wood splinters and wire wheel wires.

E-Z OUT BOLT AND STUD EXTRACTOR: A tool ten times harder than any known
drill bit that snaps neatly off in bolt holes thereby ending any possible future use.

RADIAL ARM SAW: A large stationary power saw primarily used by most
shops to scare neophytes into choosing another line of work.

TWO-TON ENGINE HOIST: A tool for testing the maximum tensile strength
of everything you forgot to disconnect.

CRAFTSMAN 1/2 x 24-INCH SCREWDRIVER: A very large pry bar that
inexplicably has an accurately machined screwdriver tip on the end opposite the
handle.

AVIATION METAL SNIPS: See hacksaw.

TROUBLE LIGHT: The home mechanic’s own tanning booth. Sometimes called
a drop light, it is a good source of vitamin D, "the sunshine vitamin",
which is not otherwise found under cars at night. Health benefits aside, its
main purpose is to consume 40- watt light bulbs at about the same rate that
105mm howitzer shells might be used during, say, the first few hours of the
Battle of the Bulge. More often dark than light, its name is somewhat
misleading. The accessory socket within the base, has been permanently
rendered useless, unless requiring a source of 117 vac power to shock the
mechanic senseless.

PHILLIPS SCREWDRIVER: Normally used to stab the vacuum seals under
lids, opening old-style paper-and-tin oil cans and splashing oil on your
shirt; but can also be used, as the name implies, to strip out Phillips screw
heads.

STRAIGHT SCREWDRIVER: A tool for opening paint cans. Sometimes used to
convert common slotted screws into non-removable screws.

AIR COMPRESSOR: A machine that takes energy produced in a coal-burning
power plant 200 miles away and transforms it into compressed air that travels
by hose to a Chicago Pneumatic impact gun that grips rusty bolts which
were last over tightened 40 years ago by someone at VW, and instantly rounds
off their heads. Also used to quickly snap off lug nuts.

PRY BAR: A tool used to crumple the metal surrounding that clip or
bracket you needed to remove in order to replace a 50 cent part.

HOSE CUTTER: A tool used to make hoses too short.

HAMMER: Originally employed as a weapon of war, the hammer nowadays is
used as a kind of divining rod to locate the most expensive parts adjacent to
the object we are trying to hit.

MECHANIC’S KNIFE: Used to open and slice through the contents of
cardboard cartons delivered to your front door; works particularly well on
contents such as seats, vinyl records, liquids in plastic bottles, collector
magazines, refund checks, and rubber or plastic parts. Especially
useful for slicing work clothes, but only while in use. It is also useful for
removing large chunks of human flesh from the user’s hands.

DAMMIT TOOL: (I have lot’s of these) Any handy tool that you grab and
throw across the garage while yelling ‘DAMMIT’ at the top of your lungs. It
is also, most often, the next tool that you will need after a really big
hammer
========================================================

Let me know which one is your favorite in the comment box below. I know I
have a few. Thanks, Randall for sharing with the Citroen community.

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To all you people who have been asking about my Citroën collection and which ones are my favorites, here is a tour of my mostly French garage.

It Includes:

1971 DS21 , 1981 GSA Break Special, 1956 Traction Avant Normal 11B, 1973 SM with 5 speed manual 3 liter V6 Maserati engine , Chapron (pedal car :0( ), 1987 CX GTI 2.5 Liter 5 speed, 1991 Peugeot 505 SW8, 1956 Lincoln Continential Mark II, and much, much more…

Hydronumatic Suspension demonstrated. Enjoy.

Denis Foley

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