* Union plans talks on Wednesday, partial strike on Friday
* Says a wage deal unlikely before summer vacation
* Hyundai shares close up 1.1 pct prior to the decision
By Hyunjoo Jin
SEOUL, July 16 (Reuters) - The main union at South Korea's Hyundai Motor said it will resume wage talks with management mid-week and stage another partial strike on Friday, signalling protracted labour tension at the world's fifth-biggest carmaker and affiliate Kia Motors.
"The chance is slim for us to seal a wage deal before the summer vacation which is from July 28 to August 5," said union spokesman Kwon Oh-il on Monday, adding the union will hold talks on Wednesday, but refuse overtime work on July 26 and July 27.
Workers at the top automaker in South Korea staged their first strike in four years on July 13 after negotiations collapsed amid disagreements over working conditions.
The country's once-powerful trade unions, largely silenced by conservative President Lee Myung-bak's tough anti-labour stance since he came to power in 2008, are demanding better working conditions as this year's presidential elections approach and Lee's mandatory single term draws to an end.
As well, more than 70,000 financial sector workers in South Korea voted on Friday to stage their first industry-wide strike in 12 years later this month.
The moves came as Asia's fourth-biggest economy cut its economic growth outlook as Europe's debt crisis deepened, and many South Korean households struggle to pay off heavy debts.
Hyundai Motor workers will join the umbrella Metal Workers Union in another round of the partial walkout on Friday along with unions at affiliate Kia Motors and General Motors' Korean unit.
Kwon said the union plans to engage in two more rounds of talks next week.
Shares in Hyundai Motor ended up 1.11 percent in the wider market that rose 0.27 percent on Monday, although they lost 15 percent of their value since May on euro zone jitters and labour tensions.
The eight-hour stoppage on Friday cost Hyundai an estimated 4,300 vehicles in lost production worth or 88 billion Korean won ($76.50 million), according to a company spokesman.
Carmakers usually make up production loss with extra work, but a prolonged strike could impact sales of the world's fifth-biggest automaker along with Kia at a time when its inventory is low, analysts say.