Can you use powertool dragons effect when dont have more then 3 equip card in your deck example i only 2 cards my can to get a card?

No.

Powertool Dragon equips up to 3 Equip Cards to itself from your Deck or Graveyard. It specifies 'up to 3', which also means 'a minimum of 1'. If there are less than 3 Equip cards in your Deck, you can not activate the effect.