The Lady of the Lake train, which was built in 1931 for the opening of the Kettering park's railway, was in such a poor condition that repair work got under way in March.
Now the park is calling for volunteers to help piece her back together again.
The train, built along with another, King Arthur, was retired from general service five years ago and has only appeared at special events since.
It will cost around £3,000 to return it to its former glory, which should take around 12 months – thanks to a volunteer organisation which supports the railway.
The Lady of the Lake has carried hundreds of thousands of passengers around the park in the last 75 years and its absence has been noticed.
What are your memories of the Lady of the Lake? Let us know by signing-in and posting your comments at the bottom of the page.The park's train driver David Nelson said: "Even in the short time the Lady of the Lake has been in the workshops, so many people have commented on her whereabouts and have shown great interest in the restoration.
"We hope to have Lady back in traffic this time next year and re-united with her twin King Arthur."
King Arthur may also have to undergo restoration work in the next few years.
It comes as Wicksteed Park gears up for Steam in the Park 2009 next weekend, which is also organised by the railway volunteers.
Now in its fifth year, this year's event will see three visiting engines running round the lake – Peter Pan, Chaloner and Paddy There will also be steam-powered boats on the lake and vintage vehicles around the station.
It will be open on Saturday, July 11, from 10.30am to 9.30pm, and on Sunday, July 12, from 10.30am to 5.30pm.
On the Saturday evening there will be live music, a bar, food and steam trains until 10pm.
Anyone who would like to bring a vehicle to the event or who would like to help with the restoration work is asked to telephone the park on 01536 512475 or they can email
railway.wicksteed@tiscali.co.uk.