CHICAGO, March 8 (Reuters) - UAL Corp. (UAL), parent of United Airlines, on Friday said it has stopped seeking investors for its business jet unit Avolar and wants to halt further investment of its own. UAL also said Stuart Oran will step down as Avolar president on Friday and Doug Hacker will serve as acting president of the unit, which sells shares in business aircraft. UAL said it was pursuing a plan to enable the unit to become profitable without further investment from UAL. UAL launched Avolar in December and said it wanted to sell a majority stake in the unit to investors to relieve the carrier of the burden. UAL is working to reverse record 2001 losses. "This move is consistent with our previously stated intentions to protect United Airlines from further financial exposure to this business and to achieve the best return for UAL on its investment," UAL Chief Executive Jack Creighton said in a statement.