Palindrome and Longest Palindrome

longestPalindrome.js

function checkPalindrome(word) {
  var arrayStart = word.split('');
  var arrayRev = [];

  for (i = arrayStart.length-1; i >=0; i--){
    arrayRev.push(arrayStart[i]);
  };

  if (arrayStart.length > 1) {
    return arrayStart.join('') == arrayRev.join('')
  } else {
    return false
  }
}

function getSubstring(word, index) {
  var new_word = '';

  for(var i = 0; i < word.length-index; i++) {
    new_word = new_word + word[i];
  }

  return new_word;
}

function longestPalindrome(word) {
  var longest = '';
  var final_word = '';
  var adjusted_word = word;

  for (var i = 0; i < word.length; i++) {
    adjusted_word = getSubstring(word, i);

    for (var j = 0; j < adjusted_word.length; j++) {

      for (var k = j; k < adjusted_word.length; k++) {
        final_word = final_word + adjusted_word[k]; 
      }

      if (checkPalindrome(final_word) && final_word.length > longest.length) {
        longest = final_word;
      }

      final_word = '';
    }
  }

  return longest;
}