Fuel tank sender

[jeans_old_man]

Thats the tricky part. The winding needs to be close-wound so that the wiper slides over it smoothly. My first attempt was too spaced out. It required about 90 turns to get to 60 ohms and when spread out over the full length of the armature it was a bit rough.

I have ordered some 0.25mm dia resistance wire (30AWG?) which is 26 ohms per meter. I will need 2.3 meters of wire and I am hoping that 115 turns will give me the correct resistance. Fortunately, this type of wire is readily available from ebay as it is used to repair 'Vape' machines.

I bought thin tufnol sheet (cotton laminated plastic) from RS Components to wind it onto and to provide the backing that insulates it from the case. After winding it I varnished it on both sides to hold the wire in place before cleaning off the working surface with fine emery paper.

Your unit looks in better condition than mine was. I am sure it can be repaired. The insides are remarkably simple.

Brian

[jeans_old_man]

First of all, let me apologise. The pre-war ac petrol gauge requires a 0-30 ohm sender not 60 ohms as I posted earlier. There is some confusion though, as I have a later ac gauge without the Singer logo that works with 0-60 ohms. I suspect that should be 0-90 ohms. That would bring it into line with the Smiths units which were fitted to many post-war cars.

My gauge stopped working recently and when I opened it up I discovered that the wire-wound resistor inside the gauge had disintegrated. This is not surprising as when the tank is empty it is dissipating 1.5 watts! No wonder then that the gauge 'fogs-up' in damp weather!

In desperation I ordered a 'universal' gauge and sender from the internet. The gauge requires a sender with 220 ohms empty and 20 ohms full. Fortunately, the correct sender came with it. The bezel is black so I ordered a chrome from elsewhere on the net. After a few tweeks this is the result:

Now all I need is a decent pointer!

Regards
Brian

[davida]

Hi

To the person who is going to use a tank unit from a Bettle have you checked if it it has the matching resistance for the gauge?

My most recent use of VDO products was the gas tank on my Bantam. Via my local Speedometer shop VDO supplied an adapter for the five and six screw holes, an adjustable depth tank unit, and a 52 mm diameter gauge to put in the dash.
I can send pix if necessary

David A [not the other David]