(Corrects "1,046 billion" to "1.046 billion" in para 8)
PARIS, Dec 5 (Reuters) - Airbus and its engine makers have acted to try to shore up the value of second-hand A340 aircraft as the European planemaker tries to reduce its financial exposure to depressed market values of an aircraft that it no longer produces.
Airbus has told bankers, airlines and other owners of the aircraft that it is working on plans to increase the maximum capacity by 8 percent to 475 seats in a bid to make it more attractive to airlines looking to replace Boeing 747-400s.
Britain's Rolls-Royce is also restructuring engine service contracts so that airlines can maintain the aircraft's four engines for a similar cost to servicing the two General Electric engines on the rival 777-300ER, according to industry presentations released on Thursday.
The move comes after parent EADS said in its 2012 annual report that Airbus was "currently engaged in taking mitigation action to reduce the impact of asset value guarantees falling due in the coming years relating to A340s in particular".
Airbus stopped making the A340 in 2011 after improvements in engine technology caused airlines to switch to two-engined models such as the Boeing 777 and, in future, the A350.
But it has been left with a financial exposure to the aircraft after issuing guarantees underpinning its resale price when striking deals to sell it during a period of weak demand.
Additionally, it faces potential losses on deals to buy back old A340s as it sells new aircraft of other types, people familiar with the matter said.
As of 31 December 2012, EADS had 1.046 billion euros of asset value guarantees outstanding, excluding 333 million euros where the risk of execution was considered to be remote.
It says the risk covers just part of the residual value of the aircraft and is included in total EADS provisions for asset value risks of 712 million euros, as of Dec. 31 last year.
The company does not break out the guarantees by plane type but analysts say the A340 makes up a significant share.
Industry sources say airlines have begun breaking up old A340s because their parts are sometimes worth more than the cost of scrapping the plane. Some have been trying to sell them because of the perceived inefficiency of running four engines instead of the now-standard two engines on long trips.
Some 25 second-hand A340s are currently posted for sale.
Airbus officials urged a special meeting of A340 owners hosted by Airline Economics to reconsider the value of the four-engined aircraft and argued it could hold its own as an interim long-haul plane before the arrival of the new A350.
Airbus said it is working to get the plane certified for 475 seats in all-economy seating. (Reporting by Tim Hepher; Editing by Sonya Hepinstall)