[Roostboy102]

They CAN be cleaned! Mine looked like they were in a jar of molasses for 5 years and it runs now... here's my method take it fwiw:

Soak them in carb cleaner/kerosene/whatever you use
Blow them out both directions with carb cleaner
Take them inside and boil them for 5 minutes or so (in water)
Oil the seals and reinstall

You could maybe redo the cleaning/boiling another time to be sure but it definitely worked for me. I got the idea from googling it and it worked! Again take it fwiw!