* Worst-case scenario seen at total shutdown of 2-4 weeks
* Pretax hit from 4-week shutdown 2.4 bln eur - Commerzbank
*, could be hit hardest - analysts
* Some say shutdown may be offset by flexible working hours
By Maria Sheahan
FRANKFURT, March 25 (Reuters) - European carmakers face production cuts and a squeeze on profits if difficulties persist in sourcing car parts from Japan, with some analysts saying they could lose up to 2.4 billion euros ($3.4 billion) of annual profits.
Some companies in Europe have already started cutting production as problems mount at Japanese parts makers, hit by the effects of the devastating earthquake and tsunami, in turn hampering carmakers and suppliers around the world.
European carmakers get electronic parts, semiconductors and some mechanical parts such as gear boxes from Japan.
Some say it could be months, rather than weeks, before production gets back on track in Japan, where lost production in the two weeks since the quake tops a third of a million vehicles. [ID:nL3E7EC03B]
Commerzbank said in a worst-case scenario of a complete shut-down of Japanese production for a month -- which it said was not very likely -- European carmakers could take a 2.4 billion euro ($3.4 billion) hit to pretax profit in 2011.
Italy'sand France's Peugeot Citroen would likely be worst hit because they are less profitable than for instance their German peers.
Modern cars have as many as 30,000 parts supplied by many different component makers. A single missing bolt can halt assembly lines and set off a chain reaction in the industry's famed just-in-time manufacturing process.
Research firm IHS Automotive said a shortage of parts stemming from the quake may cut global vehicle output by 30 percent within six weeks in a worst-case situation. [ID:nN24186350]
PSA has started to cut production at some European sites after Hitachi , which supplies it with air-flow meters for diesel engines, was hurt by the quake. [ID:nLDE72N06E]
In a knock-on effect, German automotive cables and wires maker Leoni will lose 3 million euros a week from Peugeot's production cuts, WestLB analyst Henning Cosman said, citing the company's management.
Commerzbank analysts said in the worst case of total production stoppage for one month, PSA would lose 65 percent of 2011 pretax profit -- including lost profits and fixed costs for the month --44 percent and Fiat 81 percent.
Pretax profit at Germany's, and , Europe's biggest carmaker, would take a hit of between 22 and 30 percent, Commerzbank said.
HSBC analyst Horst Schneider saidcould be hit by bottlenecks in the supply of transmission components and some sensors it buys in Japan.
"Even if some components could be sourced from other suppliers, we could imagine that this might lead to some extra costs, which could drag down the EBIT (earnings before interest and tax) margin at VW for one or two quarters," he said.
Metzler Equities analyst Juergen Pieper said his worst-case scenario envisaged a production stoppage of no more than two weeks, equivalent to about 4 to 5 percent of annual sales, which he said most carmakers could offset with labour adjustments.
"That is in a range that can be compensated with additional shifts at a later point in time, with shortened working hours or by sending workers on vacation."
So far, German carmakers and automotive suppliers have said they have enough parts to get by without fresh supplies, and some have said they would not be impacted because they do not do a lot of business with Japanese companies.
But they are already looking at cutting production, according to Germany's Federal Labour Office. [ID:nLDE72N198]
"According to our technology team, 21 percent of global wafer capacity is still down and key chemicals could be in short supply soon," Commerzbank analysts said. (Editing by David Holmes) ($1=.7062 Euro)