After some four decades of silence, "Clotherholme's Big Ben" is chiming again, thanks to a new caretaker who gave up his weekends to bring it back to life.

For the better part of half a century, the clock above Ripon Grammar School has been right twice a day. Now it is right all the time.

The school's handsome 1889 clocktower sprang back into life shortly before the start of the new school year, the result of around 140 hours of painstaking work by caretaker Matthew Buller, who joined the school only last October and set about the restoration almost immediately.

"It was relief, excitement and overwhelming joy," he says. "To look back from where the project started, to where it is now is very rewarding – but I would be lying if I said I didn't miss my free time at the weekends."

The job turned out to be rather larger than he had bargained for. The mechanism and pulley system were stripped down to individual components and freed of decades of paint, rust and grime. Brass parts were soaked in ammonia and brought back to a shine with fine steel wool, and every one of the clock's thousands of gear teeth had to be cleaned by hand.

"I ambitiously thought it would take a couple of hours to clean everything up," Matthew admits. "I then booked off two weeks of holiday for the other six days it took. And the gears are only about 30 per cent of the total work."

Scaffolding went up so the bells could be safely lowered and their straps and hammers restored, and a new 5mm steel cable was fitted to carry the 368kg of weights that drive the clock. Along the way, Matthew found traces of earlier repairs: three replacement gear teeth and a specially made bracket where the cast iron of one barrel had once snapped.

The clock has a distinguished pedigree. Built by W Potts & Sons of Leeds, it follows a design by Sir Edmund Beckett, later Lord Grimthorpe, the man behind the mechanism of Big Ben itself. It is thought to have last kept proper time some 40 to 50 years ago.

For sixth former William Renton, who was in the tower when the bells first rang out, it was a memorable moment. "I immediately knew that all of Matthew's hard work had paid off," he says. "It chiming again – with the correct time! – really brings a great sense of community to the school."

The gratitude extends well beyond the school gates. One local resident wrote to Matthew simply: "On behalf of all the folk who drive past the school, thank you." A public appeal raised more than £2,100 against a £1,500 target, with the surplus going towards a weight chute, sand cushion, lighting and future maintenance. A television production company has also been filming the restoration, with details of the programme still to come.

Headmaster Jonathan Webb believes the achievement goes deeper than engineering. "His extraordinary dedication has brought more than an old clock back to life," he says. "He has restored a living piece of RGS history."

For now, Matthew winds the weights every day, a ritual he hopes to stretch to a six-day cycle once he has the measure of the old mechanism.

Ripon, of course, has always had the Hornblower to mark the passing of time. Clotherholme, at last, has its voice back too.