VDO fuel gauge : how to chose it - help needed from electricity spec.

I have tested my exit of the fuel sender (my tank is at the rear, it is a 71 CJ5).

The datas are :73 ohms empty 23 Ohms = 1/2 10 Ohms full

I found a resistance of nearly 76 first test; I added 15 liters and it came to 56 ohms.
I moved the car to see if there is a variation of this result, it was changing a bit.

My electric contact were not very good so I believe that there was more resistance than the good result with good contacts.

At VDO they offer 3 types of gauge for the dash) : Three resistance values are available, 10-180 ohm, 240-
33 ohm and 90-0 ohm.

I believe that to use the VDO sender unit is a problem of adaptation. Possible, but time to spend.

See pages 61-64 for ALAS I & II fuel senders
For technical specifications and dimensions, please visit our website at www.vdo.com/usa

After testing my dash gauge it seems to me that it is in short circuit.

My opinion is that I prefer to put an independent gauge and forget the cluster of gauges.

Already I have a temperature gauge from Willys WWII model, with direct sending.
A oil pressure gauge from Willys WWII direct control.

I understand that the sender unit is a rheostat, so when the tank is full there is very few length of wire so the resistance is small.

At the opposite, when empty, the arm of the sender goes down and uses a maximum length of wire, so the resistance is high.

I want to have a true result so VDO is maybe the solution. ??

An other solution is to buy a STACK fuel gauge with adaptabilty from 0 to 280 ohms, more expensive.

ST3315 Fuel Level (programmable).


What I see it is that it is better to get good gauges and adapt them to control the CJ5.

Some of you have to chance to have all working well, good; but for me it is always a surprise.

 

The perfect answer. I look for this since some time; I thought that I would find my answer in 4x4 catalogs.
I never thought that the dash fuel gauge mixed with the odometer could be out of use, it is probably due to many mistakes in my Jeep concerning wiring.
I am near the good result now, but it is difficult to find theses parts when you are not in the car business.
I am astonished to see that there are any gauge with a range 10-73 ohms like mine, and also with Jeep logo.

And there are also gauges for temperature of transfer case, just need to fix a sender unit and you can control all.

Thanks a lot.