I pulled my fuel level sender today and the wires were totally gone. I can see where the reserve light wire is supposed to go. How does the nicrome wire connect at the bottom? Is it just wrapped around the plastic? There also looks like there can be 2 nicrome wires, one on each side of the float. Do I need 2 or is it supposed to have just one?
Thanks

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Will
94 E420
82 300DT
77 F250 4x4 429 Cobra Jet
69 Thunderbird 429 Thunder Jet
92 Mitsubishi Galant VR-4

It is soldered. If they are gone completely your best bet is probably replacing the whole thing. Soldering them takes a master solder-er/nerd to accomplish. I had to solder one back in place on mine, and it tested my abilities.

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It takes two nichrome wires. The way it works is that electricity goes down one wire from one of the two closely spaced connections on top, makes contact with one side of the float, travels through the float to the other wire, and then goes up the second wire and exits on top through the other connection. Thus an empty tank routes the current through the maximum length of nichrome wire, and a full tank routes it through the minimum.

I don't think it is strictly necessary to have a soldered connection on the bottom from a functional standpoint. However, a soldered connection to the tab at the bottom positions the wire properly so that the float contacts work well. You might be able to get by with wrapping the nichrome wire around the arm at the bottom, but you should pay careful attention to do the same treatment for both wires - that way if you introduce an offset, it only twists the float a little and doesn't force the contacts on the float to compensate for an out of alignment wire. You definitely will need soldered connections at the top.

Kurt

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- '79 240D - engine swap complete! Engine broken in! 28-31 mpg! Lovin' the ride!
- '86 190D (W201-126) - 2.5 NA engine, 5 speed, cloth interior, manual climate controls, 33-34 mpg (sold to forum member).

Do you have the pice of wire that broke off? if you do go to an electronics shop and get about half a meter of the same wire, then take a picture of the sender unit (fuel floater) with the metal tube off, I can draw and show you how it goes... soldering the two ends at the bottom is not so hard.... I've done it and it works fine!

Jeremy

Well, my float did not have the tube over it, and the bottom is plastic, with the one tab for the reserve light wire. am I missing more than just the tube? I will try to get new wire from radio shack today, and attempt to fix it myself. If they don't have the wire then Ill hit up the junk yards. At least then I could find a complete unit.
Thanks for the help

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__________________
Will
94 E420
82 300DT
77 F250 4x4 429 Cobra Jet
69 Thunderbird 429 Thunder Jet
92 Mitsubishi Galant VR-4

I do not think Radio Shack will have that wire. Seems like all they want to sell now is Cell Phones.

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RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K

See this thread for a DIY on a 124 sender. The 123 and 124 senders are similar. Only one wire is resistance wire, the other is plain wire, a contact for the "low fuel" light. Nichrome is difficult to solder -- to do a really good job you must use silver solder. You are better off finding a used good unit from a forum member. Put a WTB notice in the parts section.

Jeremy

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Our all-Diesel family
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This can be fixed! I didn't use "silver solder" though didn't have any... so I used normal solder and it works fine!
there is like a silver tube that goes over it ... like a cover

Here's how it should look once its closed http://images1.carpartsdiscount.com/auto/archive/pictures/59879/600/1/P/2C4B0A2/mercedes_300d_vdo_fuel_tank_sender_oem_110_542_12_04_1105421204.jpg

if the cover is missing then it would be a good idea to buy a complete one or get a used sender unit

Jeremy