Brothers restricting access to my share in property what can be done

Sir, My grandmother made a will,dividing the land and the tubewell(common) to three of her sons.Now,she has passed away but the two of them did not let us use that tubewell neither they gave us the share in tubewell if we want to sell our's part in that tubewell.So our part of land is with out our's share of water,we have to borrow it from others though it is clearly written in the will that the third part of tubewell belong to my father.Actually they have got greedy,they want to harass us as much as possible so that they can take over our's part of land.What should we do that we can put a stay on the use of tubewell,so that even they can't use it,if we can't.Please advice me on the matter.I shall be really very thankful to you.