SF’s cable car lines to shut down for historic system overhaul

San Francisco’s cable cars click and clack up hills every day, punctuated by the occasional “ding!” But starting today the California Cable Car line will go silent.

California Street cable cars will be out of service for a week while the gearbox running four miles of steel cable under The City is replaced. Buses will provide backup service.

Today’s cable car closure marks the first in a series of replacements to gearboxes running each of The City’s four cable car gearbox lines — the California, Hyde, Powell and Mason lines — which will each be out of service in turn. Those shutdowns will be spaced out through 2019.

Though it sounds seemingly mundane, this will be the first time the gearboxes have been swapped since 1984. That’s when then-Mayor Dianne Feinstein (now a U.S. senator) netted a major overhaul of The City’s cable car barn where they’re housed, at Washington and Mason streets.

And soon the cable cars themselves will be rebuilt en masse. Though the rolling historical landmarks are continually undergoing maintenance, the agency’s 20-year capital plan shows a $42 million need to begin an “accelerated” overhaul and reconstruction of the 40-vehicle cable car fleet, according to the SFMTA.

After an overhaul they last 20 years, but right now are aging faster than the everyday maintenance can keep up with, according to the SFMTA. Other upgrades will soon follow to the cable car’s aging trackway and historic turnarounds.

“The gearbox is the first step,” said Ed Cobean, senior operations manager of the San Francisco Municipal Transportation Agency cable car division.

Each gearbox is the size of a small sedan and weighs-in at 20 tons. They are housed in the Washington Street cable car barn, which was originally devastated in the 1906 earthquake and later rebuilt.

The gearboxes are key drivers of the cable cars, and spin massive “sheaves,” which are the 30-foot-tall wheels that pull the some 12 miles of steel cables under The City. The Missouri-made steel cords are then gripped by the cable cars to move.

Essentially, without gearboxes cable cars can’t run.

That raises the stakes for the $6 million project, Cobean said, but his mechanics are familiar with much of the replacement process. It starts by unthreading the steel cables, which are actually two cables woven into one by workers called “splicers.”

On Thursday morning at the brick-laden cable car barn, Cobean pointed to a 15-foot-tall spool looped with steel cables that looked like it fell from a giant’s sewing kit. “The way I like to explain it,” he said, “take two pieces of Twizzler licorice and make it into one.”

The steel cables are replaced on the California Cable Car line every six months, and about every four months on the three other cable car lines, he said.

“By hand,” he added. It takes between six and eight hours to unweave the cables.

So SFMTA’s cable car mechanics are familiar with much of the process, Cobean said, but no members of his team were around during the first cable car barn overhaul — which makes sense, as it was 33 years ago. Some of the process is unknown.

That isn’t a problem for Robert Bergesen, mechanical and shop superintendent at the cable car barn.

Bergesen, a tall, bearded man, was a defense contractor for 18 years. He was a mechanic specializing in repairing older machinery that was so out of date, few living had knowledge on how to repair it. Bergesen also repaired experimental prototypes.

That work prepared him for maintaining the nearly 150-year-old cable car system, he said.

“There’s no owners’ manual to help you when this stuff breaks,” Bergesen said, standing near the cable car barn’s spinning shivs.

“You’ve gotta figure this stuff out,” he added.

Bergesen noted the trades involved in cable car maintenance have slowly vanished from the U.S., with a smattering of specialists on the East Coast, though most are now in China.

Even the new gearboxes came from a subcontractor, Nuttall Gear, in Niagara Falls, N.Y.

The knowledge needed to repair the outdated, but highly valued, world-famous technology is unique, Bergesen added.

“There’s a lot of pride in the cable car system,” he said.