Ewarts tap plungers

Has anyone got a tip for
Preserving the condition of spare plungers
and
Reviving a plunger that's dried out. A friend says put it boiling water , but it doesn't seem to work for me!

They're getting too pricey to just bung a new one in especially as some of the new ones seem to be of dubious quality.

You could just fit a new cork

https://www.feked.com/fuel-tap-cork-for-pull-on-type-fuel-taps-3-8.html

https://villiersservices.co.uk/product/fuel-tap-cork-round-type/

Then maybe stick them in a small sealed jar with a bit of paraffin ?

I put a smear of petroleum jelly on the new cork when I fit it.

One of our club members used to flash a lighter across them, they swell up then. Not a recomended way though!

Pete.