20110315 toyota japan plant 54
On June 5, 2009 a factory worker assembles Prius hybrid vehicles along the assembly line at Toyota Motors' Tsutsumi factory in Toyota, Aichi prefecture. - 

Jeremy Hobson: There are reports this morning that workers are being sent back in to try and cool reactors at the Fukushima Dai-ichi plant in Japan. They were withdrawn from the plant hours earlier because of surging radiation. Meanwhile the economic effects of all of this continue to ripple across the globe. Many Japanese auto plants are still shut down which could cause problems for U.S. carmakers.

Marketplace's Alisa Roth reports.

Alisa Roth: Subaru has canceled overtime shifts at its American plant. It had been running them for more than a year. But now it's worried about running out of parts.

Michael McHale is the spokesman for Subaru. He says the company's trying to assess the situation both here and in Japan.

Michael McHale: In the U.S., the majority of our parts are locally sourced, but there are a few critical components that come from Japan, so it behooves us to then go check rather than making cars we can't finish.

He says it'll be days before Subaru knows what kind of shape its Japanese suppliers are in. And even if those suppliers are working, there are big logistical problems, like rolling blackouts and damaged roads and ports.

Michael Robinet is an auto industry analyst at IHS Global Insight. He says to varying degrees, the global auto industry's supply chain runs through Japan.

Michael Robinet: Really there is nobody that is not going to be affected by this at some point.

He says that means production hiccups not just for the Japanese carmakers, but the Big Three, the Europeans and the Koreans too.

I'm Alisa Roth for Marketplace.