The Official 356Talk Forum

Fuel level sender repair. I have a 1958 A coupe that has a problem with the fuel sender. Upon examination I found that there were drop outs in continuity when the float arm is moved from full to empty. Which repair companies can repair this type of problem? It is the original sender to the car, I wish to retain this unit for the car as it is correctly dated. Thanks W Jeff Mullis

It's probably just corrosion on the wiper/ wire coil. Remove the cork gasket and soak it in pickling vinegar for a couple days. The vinegar will dissolve the corrosion on the brass and copper wire. Then soak it in baking soda for 10 min to neutralize the acid, then rinse with water and blow dry with a hair dryer on low. It should read 0-200 ohms as you move the float.

The vinegar won't hurt the cork if its stuck. I just did one. I used evaporust and it works fine now.

I have been restoring senders for years for many of the shops out there. The A/B senders typically suffer from a worn out pivot hole leading to a bouncy needle. Broken resistor wires are also quite common and can be re-wound.

I have been pushed back on some existing restorations as my plater ran into some issues. Hope to finish these senders in the next weeks.

There is a company, Specialty Cars Service Center that repairs VDO gauges.

Mike

Joris
I have been looking diligently for that plastic isolator piece for the positive side connection.
would you share your supplier or give me a hint on where I could get one ?
The senders look amazing for sure

Very nice work Joris. My (Australian) BT6 has that isolator but it is black. Is that correct? The gauge was rather inaccurate and had erratic motion, but after some testing and cleaning of the resistor coil and associated parts (and fitting a capacitor over the terminals) it is solid and accurate now.

Mervyn / Joris
how do you clean the sender ?
do you have to take it apart, or just as per above, dip in vinegar, as per above ??

I have also used a pink eraser, rub lightly, in the Direction of the winding NOT ACROSS IT. This removes the corrosion and makes the wire bright again. But a chem dip is easier. It takes longer but no chance on breaking the wire on the coil. This is a pretty simple circuit. You can also carefully strighten the four tabs and disassemble it, unsolder the resistor and rebuild everything. It was assembled by a human, you can fix it.

I have done it both ways, but the chem dip is the easiest.

The ring terminal insulator is a DIN standard component.

where would I get a DIN terminal insulator like that ??

Jim,

Mine has the top sender and is not on the flat tank (BT6, non-US). It looks like this (mine was in much better condition). I was quite taken by the 'petals' on the ends of the float as a means to increase drag, I suspect, and dampen the action. I dismantled it before cleaning after an overnight soak in some vinegar.

All those parts not currently available I have made myself or had made to ensure an as authentic as possible result. This includes the wire shield and the insulator as well as some of the hardware for which the DIN spec has changed.

For those looking for an appropriate dated sender for their car, I have quite a few cores with different dates