A question about a feathering mechanism

[J13 Serenity]

Hello!

Does anybody knows how the propeller feathering works?
Usually, on multiengine, there is some kind of additional feathering pumps or so...
In my testing, even if the engine was stopped, propeller could still be feathered and unfeathered.
But when my mosquito had no battery and no generator, the feathering did not work.
It might be a bug, or my misunderstanding 
But is seems like the feathering requires electricity

There is no info on this in the manuals I've found

May be somebody here knows the truth? 

Thank you

[saburo_cz]

Yes, the feathering requires elecricity.
Each propeller has independent feathering pump driven by electrical motor which is supplied from batery (generator).

[J13 Serenity]

Thank you