For 25 years Morisset Centenary Town Clock has stood outside the old post office on Dora Street.

In that time, neither the wind, sun, rain nor birds have got the better of the Seiko clock's resilient little solar battery.

"The schematic diagrams that came with the clock say that the battery will need replacing every so often . . . but it's never happened," the clock's keeper Les Norris said.

"I'm absolutely amazed at how the clock has lasted all this time."

A former police chief and longtime member of Morisset Rotary Club, Mr Norris was president of the Morisset Centenary Committee when the clock was commissioned on December 18, 1988.

The Rotary club raised $1500 to buy it, and promised to keep it in good working order.

When Mr Norris put his hand up to become keeper of the clock, he had good reason to think that some painstaking maintenance might be required.

After all, the detailed instructions, circuitry diagrams and schematics showed that the clock was an intricate and complex piece of machinery.

"But the truth is we've hardly had to do anything to it," Mr Norris said.

"We do change the time for daylight saving, and about 10 years ago I climbed up to replace the glass on the [north-facing] face once, and I put galvanised wire cage over it because kids had been breaking the glass. But that's it."

Mr Norris said that despite Lake Macquarie City Council's plans to renew the CBD and perhaps replace Morisset Memorial Hall and build a civic hub, the historic clock should stay.

"We got permission from the council to put it where it's located on the corner here, and because it doesn't take up usable space, new buildings could be built around it," he said.

"And I can see no reason why the clock wouldn't keep working for another 25 years."