Eastern Airlines yesterday reported its first quarterly profit in nearly two years, $3.6 million in the third quarter, and attributed the improvement to the "favorable impact" of an employe wage-for-stock swap.

The Miami-based carrier also reported an operating profit of $60.9 million, the highest operating profit in the company's history, and its third consecutive operating profit this year.

Eastern's chairman and president, Frank Borman, also cited strong summer traffic and continued cost-cutting as factors in the earnings. But he said more cost-cutting is necessary.

The quarterly net earnings contrast with a $34.4 million net loss in the third quarter of 1983. The $60.9 million operating profit contrasts with a $17.3 million operating loss in the third quarter of 1983.

Per-share losses were 7 cents, down from per-share losses of $1.35 a year ago.

Despite the quarterly profit, Eastern posted a loss of $48.7 million ($1.69 a share) for the first nine months. That contrasts with a loss of $128.9 million for the same period last year.

IC Industries Inc., a holding company that owns Midas Muffler, Pet Foods and the Illinois Central Gulf Railroad, said yesterday that its third-quarter profits were more than double those of a year ago, with more than half of them coming on the sale of a single piece of real estate on Chicago's southern lakefront.

IC said it earned $41.9 million ($1.06 a share) on sales of $1.022 billion compared with 1983 third-quarter earnings of $19.6 million (45 cents) on sales of $955 million.

Nine-month earnings were $88.8 million ($2.22) on sales of $2.925 billion compared with 1983 nine-month earnings of $43 million (95 cents) on sales of $2.707 million.

The results for the quarter and the nine months were boosted by the sale of 80 acres of land in Chicago for expansion of the McCormick Place exposition center. IC posted a pre-tax gain of $25.7 million from the sale.

Freight loading on the Illinois Central Gulf Railroad increased 10 percent during the quarter, contributing to a 20 percent increase in revenue for the unit. The railroad earned $35.6 million, which compared with a loss of $3.2 million a year earlier.

A spokesman said the company still intends to sell the railroad, "but only under terms that are favorable to our stockholders."

Revenue from commercial products increased 13.8 percent, while income increased 46 percent, to $15.5 million from $10.6 million. IC's commercial holdings include Abex, which manufactures hydraulic equipment, and Hussman, the world's largest manufacturer of refrigeration equipment.

IC's consumer products, which include Midas Muffler, Pet Foods, and Pepsi-Cola General Bottlers, reported a decline of 1.3 percent in revenue but an increase of 3.4 percent in income.

Chris-Craft Industries Inc. said yesterday that its investment in Warner Communications Inc. was responsible for a net loss of $12.3 million in the fiscal year ended Aug. 31.

The loss was equal to $1.88 a share, after the company took a net charge of $16.9 million representing equity in Warner's losses from discontinued operation.

In fiscal 1983, Chris-Craft had net income of $4 million (49 cents a share).

Earlier this year, Chris-Craft acquired about 25 percent of the voting stock of Warner, helping the entertainment company to turn back an attempt by publisher Rupert Murdoch to gain control. The Chris-Craft holding in Warner includes about 3.5 million shares of common stock.

Chris-Craft said its losses were the pro rata portion of losses posted by Warner in the six-month period ended June 30. Warner, in turn, said its losses were due to its Atari home computer and video game business, which has been sold.

In August, Warner reported a loss of $20 million from continuing operations and a net loss of $407 million in the previous six months.

Chris-Craft said the amount WCI will realize on the Atari sale is uncertain now, and this will cause the accounting firm of Arthur Andersen & Co. to issue a qualified report on the 1984 Chris-Craft results.

Chris-Craft said income from continuing operations fell to $4.6 million (58 cents) in the fiscal year from $6 millon (79 cents) in the 1983 fiscal year because of its equity in WCI's loss from continuing operations.

For the fourth quarter, Chris-Craft reported a loss from continuing operations of $530,009 (10 cents) compared with $1.6 million (21 cents). The net loss was $17.9 million ($2.77) in the latest quarter, when the WCI equity losses were recorded. In the 1983 fourth quarter, Chris-Craft had net income of $2.3 million (32 cents). Fourth-quarter consolidated revenue was $42 million compared with $21 million in the fourth quarter of 1983.

Dow Jones & Co. Inc. said yesterday that a dropoff in advertising linage in The Wall Street Journal and Barron's magazine contributed to a 6.7 percent decline in the company's third-quarter profits.

Dow Jones, a leading publisher of business-related news, said profits fell to $26.5 million (41 cents a share) in the three months ended Sept. 30 from $28.4 million (44 cents) a year earlier as revenue rose to $232.5 million from $216.9 million a year earlier.

Nine-month profits rose to $94.7 million ($1.48) from $80.8 million ($1.26) in the first nine months of 1983, and revenue rose to $708.6 million from $632.8 million.

Advertising linage in the Journal was down 2.2 percent from an unusually robust performance a year earlier, the company said. It said linage in Barron's was also down, reflecting reduced stock market interest and activity.

In the third quarter of 1983, the Journal enjoyed an unusually large 25.5 percent increase in ad revenue from a year earlier.