Second problem of the evening. The gas gauge on my 1965 220SE works ok at the very top, but below that it bounces around up and down becoming worthless towards the bottom.

The gauge in my 1968 230s which is running, but I am taking parts from works great.
I thought I would see if I could just switch them out.
Wrong.

The 1968 is the long cylinder and the 65 is the toilet bowl model. But everything else is the same. I tested the connector by running a single wire across two of the three holes as I read about today on this board. Turned the key, gas needle smacked full. Put the cylinder sender in, sanded the posts put dielectric grease in the holes, nuts on, connected it, turned on the car. Gauge needle goes from all the way at bottom to just above empty.
Drove the car around trying to splash gas around in case the float is stuck. No change. Put the toilet sender back in. It reads just below full because the tank if full. Put cylinder sender back in 1968 turn it on and it read half tank which is correct.

What am I missing here? Is there some exotic difference in the electronics of the two so you can’t switch them?

Confused.
Thanks
Eddie

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1965 220SEb Manual

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