Fuel Tank Sender

[jockduck]

I am having problems with my fuel gauge on 1968 Mini, I pulled the sender unit and found the float 1/3 full of liquid, I checked the float for leaks and immersed the float in hot water but no bubbles. The float still floats! but were they manufactured with liquid inside?
Jock

[notamini]

Both my old one and the replacement for it did not have any fluid in them