there is a fill plug on the pump. pop it out and add some transmission fluid just to the bottom of the fill hole. leave the plug out and operated the top, you may have to go up/down with the switch a few times to get it to start moving. once it starts moving and you see the air bubbles diminish, top the fluid off to the bottom of the fill plug and reinstall the plug. note that you won't be able to get all the air bubbles out, but when the top is functional you should be good.