UPDATE 1-S.Korea says Sept crude imports down 1.6 pct y/y

* Sept crude runs at 67.17 mln bbls, down 6.9 pct on year

* Oil product demand at 60.01 mln bbls, down 2.6 pct on year

* End-Sept oil stocks at 65.34 mln bbls, down 3.5 pct on year (Adds details)

SEOUL, Oct 23 (Reuters) - September crude imports by South Korea, the world's fifth-largest buyer, were down 1.6 percent from a year earlier on a slow economy and refinery maintenance, state-run Korea National Oil Corp (KNOC) said on Friday.

South Korea's four refiners -- SK Energy (096770.KS), GS Caltex, S-Oil Corp (010950.KS) and Hyundai Oilbank -- and KNOC imported 67.99 million barrels of crude (2.266 million barrels per day) in September, compared with 69.08 million barrels (2.303 million bpd) in the previous year.

Domestic oil product demand in September was down 2.6 percent at 60.01 million barrels from a year earlier, KNOC said.

"The economy has been slow, while oil prices showed signs of picking up, which was seen damping oil demand in September," an analyst at KNOC said.

"Weakening margins and refinery maintenance affected production and exports in the month," he said, referring to South Korea's top oil refiner SK Energy, which on September 30 restarted its 240,000 barrel-per-day (bpd) No.4 crude refining unit after it was shut down for maintenance for more than a month. [ID:nSEO72997]

The country's No.3 refiner S-Oil said on Thursday that operating profit in the three months ended September swung to negative because of poor refining margins. [ID:nSEF000016]

South Korea's private crude stocks at the end of September dropped 3.5 percent from a year earlier to 65.34 million barrels.

But average crude oil stocks in the January to September period this year stood at about 70.35 million barrels, still higher than 68.63 million barrels in the same period of last year as a result of weaker oil prices.

NYMEX crude CLc1 was traded at $65-$75 per barrel in September, after trading at over $100 a year earlier. But NYMEX crude prices have gradually recovered to top $80 per barrel this month as the economy via U.S. equities showed signs of recovery. [ID:nSP147243]

Lower crude oil prices, however, have been damping demand for liquefied natural gas (LNG) in South Korea, the world's No.2 buyer after Japan, as utility companies switched to cheaper fuel oil and coal from LNG for power generation.

South Korea's LNG fell for a ninth consecutive month in September from a year earlier, customs data showed on Thursday, as the country imported 1.19 million tonnes of LNG in September, down 35 percent from 1.84 million tonnes a year earlier. [ID:nSEO72946]

For detailed figures, click for table: [ID:nSEO294143]

For a graphic, please click:

here (Reporting by Cho Meeyoung and Shin Jieun; Editing by Chris Lewis)