Does rubber lose buoyancy over time???

As titled, due to problems with my fuel tank sender/gauge. Seems to work outside tank - 20-272 Ohms on multimeter from gauge contacts and from top connection.

I can see as i put the sender back in that the float is not floating. It is the rubber variety.

So, can this float lose its ability to... float over time?

Does anybody have any idea as to a replacement bit of rubber, maybe even a link?

I'm looking to save myself the 60 odd quid to buy a new sender tbh, money's tight.

Thanks peeps!

You sure the arm is not too tight to move prperly

Try - island4x4.co.uk

quite cheap.