SEATTLE (AP) - A drive motor failure that occurred during maintenance on the 188-car Washington state ferry Walla Walla has left parts of the ferry near the engine charred and melted _ and the vessel out of service indefinitely, a Washington State Ferries spokeswoman said Friday.
The incident happened last Sunday while the ferry was undergoing routine, regularly scheduled maintenance at the agency's facility on nearby Bainbridge Island.
KING-TV first reported the damage on Thursday.
No injuries were reported.
Built in 1972, the Walla Walla, which can carry as many as 2,000 passengers, will be out of service "for at least the next few months," spokeswoman Marta Coursey said in a statement.
The damaged drive motor is one of four motors that turn the vessel's propellers.
The ferry was a week away from returning to the Edmonds-Kingston route after four months of maintenance, the Kitsap Sun reported.
"This is a serious incident and we're going to do a very thorough and detailed investigation into what happened," said David Moseley, Washington State Ferries director. "We hope to return the vessel to service as soon as possible."
Because the damage was so severe, a third-party contractor, Cadick Corp., has been brought in to help with the investigation. The state Transportation Department has also asked the state Department of Labor and Industries and the Coast Guard to help make sure all employee safety requirements were met.
Results from the investigation are expected within two to three weeks.
The Transportation Department is checking with the engine manufacturer to see whether a spare drive motor the department already owns can be used.
Other ferries will be shifted around in the system in an effort to maintain service, Coursey said.
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