Mismatched fuel Sender to Fuel gauge

[listerjp2]

Hi all

I have had the perennial problem of my fuel gauge not reading correctly.

So after a long thought I think I may have fixed the burning issue.

I had a spare Baoter 3296 variable resistor (look it up in Google) in my bits and bobs tin.

Cheap as chips to buy one.

I have just wired it in series and low and behold I am able to adjust the fuel gauge.

I have set the variable resistor so that it reads full and see if it shows empty when I run out.

Obviously I will take a fuel can just in case.

If this works then it could be used on any mismatched fuel gauges without the need for grafting etc.

Will keep you all informed.

Adrian

[jon_wilkinson]

Re: Mismatched fuel Sender to Fuel gauge

Fingers crossed but based on my limited knowledge of electronics I doubt it will read correctly across the gauge.

The best solution, albeit more expensive, is the Spiyda gauge wizard. Used one on my last Roadster to match a Ford sender to an etb gauge. Worked perfectly. No connection with the company, just a very satisfied customer.

[boustrophedon]

Re: Mismatched fuel Sender to Fuel gauge

Been there done that on Wee Beastie. A search may even find what I wrote at the time.
I take it that you have a Ford sender in a Ford tank wired to a Smith's gauge for a BL car. No simple resistor is going to match the dial to the sender across the range.
I made a operational amplifier based dongle that adjusted for gain and end points, but I was never able to make it reliable. My next step was to fit a miniature RC servo in the dial and control it from a programmable chip. I gave up.

The Ford sender is 75 ohm empty and 10 ohm full. The Smiths gauge on the other hand is expecting a resistance of 260 ohms empty and 20 ohms full. The circuit is fed from a 10V regulators sometimes to be found on the back of one of the dials The gauge is effectively a ammeter measuring the current, which it measures using a resistance coil wrapped around a bimetallic strip. The resistance of the heater wire in the gauge is about 0.1 ohm by measurement on a spare dial, but it is not significant and does not need to be taken into account when designing a circuit to compensate.

[listerjp2]

Re: Mismatched fuel Sender to Fuel gauge

Oh well, I will see what happens, it hasn't cost me anything except my time.

Onwards and upwards.

Adrian

Been there done that on Wee Beastie. A search may even find what I wrote at the time.
I take it that you have a Ford sender in a Ford tank wired to a Smith's gauge for a BL car. No simple resistor is going to match the dial to the sender across the range.
I made a operational amplifier based dongle that adjusted for gain and end points, but I was never able to make it reliable. My next step was to fit a miniature RC servo in the dial and control it from a programmable chip. I gave up.

The Ford sender is 75 ohm empty and 10 ohm full. The Smiths gauge on the other hand is expecting a resistance of 260 ohms empty and 20 ohms full. The circuit is fed from a 10V regulators sometimes to be found on the back of one of the dials The gauge is effectively a ammeter measuring the current, which it measures using a resistance coil wrapped around a bimetallic strip. The resistance of the heater wire in the gauge is about 0.1 ohm by measurement on a spare dial, but it is not significant and does not need to be taken into account when designing a circuit to compensate.