AMSTERDAM - HSBC has this week launched the 2 billion pound ($3.1 billion) sale of its UK rolling stock leasing company as it builds its balance sheet by shedding non-core assets, people familiar with the matter said.

Infrastructure funds of Macquarie and JPMorgan have already teamed up to bid for the business, while UK-based investment firm Star Capital is also interested among other possible bidders, two people familiar with the matter said.

The unit, HSBC Rail, owns a third of Britain's rolling stock and is one of three train leasing companies that passed into private hands during the 1990s.

HSBC hopes its steady cashflows, derived from its long-term contracts, will appeal to private equity firms and infrastructure funds.

HSBC expects the sale to be done at book value, or slightly at a premium to the book value, a source familiar with the matter said.

The source added that HSBC sent out information to potential bidders this week expecting expressions of interest in late March, with final offers expected to be sought about a month after that.

ENTERPRISE VALUE

HSBC is assuming the asset has an enterprise value of 2 billion pounds, based on a staple debt package of 1.7 billion pounds, that includes 200 million for capital expenditure, two people close to the deal said on Wednesday.

An HSBC spokesman declined to comment. A Macquarie spokeswoman also declined to comment, while JPMorgan and Star Capital did not immediately respond to requests for comment.

HSBC has been planning the sale of its rail unit since 2008, several sources said, but its plans were derailed as the financial crisis made commercial bank debt -- likely to be key to the sale's success -- scarcer and more expensive.

The rail unit has a UK fleet of over 4,000 trains and its sale follows the rationale of the divestments of the other two UK train leasing companies, as banks look to raise cash by disposing assets not central to their businesses.

In June 2008 Royal Bank of Scotland agreed to sell its train leasing firm, Angel Trains, to a consortium lead by Babcock & Brown -- now Arcus Infrastructure -- for an enterprise value of 3.6 billion pounds.

This was followed by the sale of the British rolling stock firm Porterbrook by Abbey National -- now part of Santander -- to a consortium of Deutsche Bank, LLoyds TSB and BNP Paribas-sponsored Antin Infrastructure Partners for 2 billion pounds.

HSBC's shares were the top performer in the FTSE 100 index at 1337 GMT, up 2.2 percent.

HSBC's own investment arm and Rothschild [ROT.UL] are advising the British bank on the sale, several sources said. (Editing by Dan Lalor and David Holmes) ($1 = 0.6482 pound)

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