Staff are casting their eyes over 4.2km of overhead tram cables on a stretch of line installed in 1942 to ferry workers to the Bendigo Ordnance Factory in Finn Street during World War Two.

Bendigo Tramways has so far made do with patching parts of the overhead network but that is becoming increasingly expensive as the 77-year-old section of line ages, operations manager Luke Treble said.

"Given the amount of track and us being a not-for-profit, you can see there's quite a lot of maintenance in that," he said.

The tramways currently pays contractors to do maintenance work at least monthly across its network and the costs involved can be massive, Mr Treble said.

"They've got to be qualified linesmen and we don't have any on site. So it's a bit of a challenge as far as resources are concerned," he said.

"Once we have something new the maintenance costs should drop dramatically. So we are hoping to recoup those costs over the life of the asset."

It is too early to tell how much money the upgrades will cost or how long they will take to complete, Mr Treble said.

"This is about designing, from scratch, a new system and then a roll-out over successive financial years," he said.

"At this point it is looking like a staged approach over three to five years to replace the northern part of the network," he said.

Pictures: Walk again amongst the machines at the Bendigo Ordnance Factory

Bendigo Tramways is considering a modern system similar to what Melbourne's Yarra Trams and other groups use, Mr Treble said.

"Right now all your terminations and fittings are 1943 equipment, whereas now we would be going with what the best-practice is," he said.

Yet the plan is still in its earliest days and Mr Treble said work was currently focused on "assessing what we've got".

"Some sections may not need to be renewed," he said.

Much of the Bendigo line dates back to the 1920s.

An 80-metre stretch was upgraded in June as part of track and drainage works in the CBD.

That included fixing tracks and sleepers that had subsided and left minimal clearance between the bottom of trams and some sections of the road pavement.

Tramways CEO Peter Abbott hoped more sections could be restored in coming years.

"We are also working to keep the fleet running. There are 100-year-old trams and there's always something going on here at the depot," he said.

"Over time we are investing a lot of money in our capital to keep our infrastructure going."

Much of what needs to be renewed is discovered when crews of volunteers and staff inspect the network every two weeks.

A two-to-four person crew rolls out on a "scrubber tram" that inspects and cleans the track.

The tram uses a silicon carbide bricks pushed onto the tracks to rub down the head of the rail.

"That gets rid of deformities in the rail and keeps the track clean," Mr Adams said.

"The points are the blades you see in the track that turn the direction of the tram," Mr Treble said.

Workers and volunteers also clean debris out of the "points" on the line.

"Our team takes the points to pieces and cleans out all the leaves and other gunk that gets into them."

More news:

The scrubber tram also has an air system fitted to help blow gunk out of the points, tram maintainer Mr Adams said.

He spends much of his working life in inspection pits that run underneath the tram depot working on undercarriages.

"I grew up in Adelaide and I grew up with some of the trams here, which ran from Adelaide to Glenelg," he said.

"We actually had a school excursion come out from Adelaide a few weeks ago and the teachers were saying 'oh that one was one of the Adelaide trams'."

Mr Adams is a boiler-maker by trade but has done a range of jobs from traffic management to working with overhead cranes.

"For nine years I was also involved in a voluntary capacity at the Tramway Museum in Adelaide. A couple of expert volunteers showed me how to service trams. Then I was offered a job doing this," he said.

It is a rare job, these days.

"It's fairly hard to come by. This is equipment most people don't even think exists and the techniques to maintain them are hard to come by," Mr Adams said.

"You have to be in the right circles to learn how to maintain this stuff.

"There are some cranes out there - not very many nowadays - that would have controls similar to this 1915 team but they are few and far between."

Trams are serviced every fortnight, with bigger inspections every six to eight weeks.

"We check the brakes are adjusted and make sure the controls are working as they should," Mr Adams said.

"We are also trying to keep parts nice and clean because if something does go wrong we are more likely to find it."

There are seven trams currently in high rotation with as many as 10 circulating at busy times, Mr Adams said.

There are also plans first announced in May this year for five new workshops that will in part pave the way for more restorations of historic trams.

It is part of plans to become a "national restoration centre" not only for trams but train carriages, buses and "anything" else, Mr Abbott said at the time of the announcement.

"It allows us to expand our operations and workforce (with) the surplus made from the workshop going to retaining Bendigo's iconic talking trams," he said.

Works on the the Bendigo Tramways Development Plan are expected to start next year and include the creation of 20 manufacturing jobs as well as the creation of 10 ongoing jobs.

Have you signed up to the Bendigo Advertiser's daily newsletter and breaking news emails? You can register below and make sure you are up to date with everything that's happening in central Victoria.