A double-decker piece of Dion's history could end up in museum

The bus, No 6057, was one of 21 double-deckers built for private bus companies between 1947 and 1950 and is the only known survivor.

The Dions' bus company used it on the signature Austinmer run but also down south - picking up workers and delivering them to the Port Kembla Steelworks - before it was retired in 1964.

Wauchope man Brian Mantle has spent decades restoring the bus since he acquired it from the Dion family in the early 1980s.

Now the Sydney Bus Museum is hoping to raise $50,000 via a Go Fund Me campaign to buy the bus and fill a missing piece of its collection.

"This bus has been immaculately restored over a long period by a museum member and we now have the opportunity to purchase it and bring it into the museum collection for permanent display," a museum spokesperson said.

Dions Bus Service managing director Les Dion said he was "110 per cent loving" the museum's efforts to purchase the bus - and the family had already contributed a "considerable chunk".

Mr Dion said it was great timing, given the company celebrated its centenary last year.

"Last year we had the 100-year anniversary and our legacy was to show some video and some of the family history," Mr Dion said.

"Now we have this this double-decker bus from 1948 that's been fully restored back to original condition. If the Sydney bus museum secures the bus, then that's something for everyone to see."

Mr Dion said the bus had been sitting in a shed at the back of the family home where "they would throw junk in it".

The decision to build Memorial Drive was the catalyst in the family deciding to hand the bus over - the rear of the family property backs onto the North Wollongong on ramp.

"Because Memorial Drive - or back then it was the Northern Distributor - was being built, the RTA carved off a piece of the family property on which that bus was sitting.

"So the family had to get rid of it anyway. It was just sitting in a shed so it was in not great condition, but it hadn't rusted away, which is a good thing.

"And, so Brian came along and offered to take it away.

"It was a good storage shed with the bus in the middle and then eventually that had to go. It was the best thing the family ever did and I don't think they expected it to be coming out 100 years down the like from when they first started."

Though it was a challenge to remove it from the shed; first the tyres had to be pumped up and then it was realised the roof of the shed had sagged, meaning the entrance was actually around 20 centimetres lower than the roof of the bus.

Scaffolding jacks had to be used to return the roof to its proper location before the bus could be removed.

Mr Dion said the double-decker buses worked in certain circumstances but, today, it wasn't suitable to have one on the Austinmer-Wollongong run.

With multiple stops, and the wait for people on the top level to make their way down and off the bus, sticking to the timetable would be impossible.

While they can resolve a "capacity issue", Mr Dion said they worked best picking up a lot of passengers at one stop and driving them to a specific location.

"When you think about the logistics double-deckers have a place," he said.

"You've got to have the right service, the right number of stops and the right schedule to make sure that actually provides a service that you're looking for.

"It's the right tool for the right job. If you had to wait for everyone who wanted to get up on the top to get off at their stop on the way Wollongong to Austinmer you'd never get there."