General Electric Co. said yesterday that third quarter net income rose $41 million from a year ago to $268.5 million ($1.18 a share) from $277.3 million ($1.01).

Sales totaled $4.35 billion, compared with $3.77 billion in 1976.

For the nine months, net income was $755.8 million ($3.33) compared with $63.4 million ($2.83) a year ago.

Sales rose to $12.79 billion from $11.17 billion.

Eastman Kodak Co. yesterday said third quarter profits increased to $188.07 million ($1.17 a share) compared with $170.57 million ($1.06) on sales of $1.54 billion against $1.38 billion for the same period a year ago.

Nine month earnings fell to $417.30 million ($2.59) from $428.96 million ($2.66) on sales of $4.09 billion compared to $3.75 billion for the same period a year ago.

Chairman Walter A. Fallon and president Colby H. Chandler said in a joint statement that foreign currency translations had a $12 million "unfavorable effect" in the third quarter compared with $15 million a year ago. For the nine months, the negative impact was $42 million against $35 million in 1976.

Westinghouse Electric Corp. reported record earnings of $189.7 million ($2.16 a share) in the first three quarters of 1977, more than in any first nine months in its history.

Chairman Robert E. Kirby said year-to-date earnings were up 18 per cent from 1976 on sales of $4.47 billion, compared with profits of $160.8 million ($1.83) on sales of $4.46 billion a year ago.

Third quarter profits amounted to $72.5 million (82 cents) on sales of $1.51 billion, compared with profits of $59 million (67 cents) on revenues of $1.47 billion in the same period of 1976.

Westinghouse reduced its ownership in Ateliers de Constructions Electriques de Charleroi, a Belgian affiliate, to a minority position earlier this year. Its sales are not included in the 1977 results.

Kirby said the exclusion of ACEC sales from 1976 results would give Westinghouse a 10.6 per cent sales gain in the third quarter of 1977 and 8.1 per cent for the year-to-date.

He noted that power generation equipment operated at a trimmed loss on higher volume in both periods of 1977. Net income from transmission and distribution apparatus improved in the third quarter from a year ago, but trailed in the nine months compared with 1976.

CBS Inc. reported an increase in third quarter net income to $43.8 million ($1.57 a share) from $40.8 million ($1.43) a year ago.

Sales were $655.4 million compared with $524.7 million.

For the nine months, the broadcaster's net income was $131.7 million ($4.68) compared with $116.1 million ($4.07) last year. Revenue rose to $1.94 billion from $1.57 billion.

J. P. Morgan & Co., parent of the nation's fifth largest bank, reported relatively small third quarter earnings gains yesterday.

Net income was $54.3 million ($1.33 a share) against $51.7 million ($1.27) last year. For the nine months, net income was $155.8 million ($3.83) compared with $141.9 million ($3.54) in 1976.

The company said net income for the nine months this year were reduced $8.7 million due to nonaccrual of interest on certain loans and accrual at reduced rates on others. The comparable penalty to net income in the corresponding period of last year was about $11.5 million.

The current year's net income was further hurt by $1.8 million, compared with $1.3 million a year ago, attributed to nonaccrual of interest on loans that had been canceled by the acquisition of real estate or related assets and on funds spent or advanced in connection with the acquired assets.

Foreign currency translation gains of $800,000 were included in 1977 nine months net compared to such gains of $2.4 million in the year-ago period.

Allis-Chalmers Corp. earned $11.3 million (93 cents a share) in the third quarter, up from $9.4 million (71 cents) a year ago as sales rose to $379.5 million from $364.4 million.

For nine months, Allis-Chalmers earned $53.9 million ($4.44) on sales of $1.168 billion compared with $46.9 million ($3.61) a year earlier, when nine months sales were $1.15 billion.

Chairman David C. Scott said the gains were made in spite of softness in the farm machinery business, one of the firm's major lines.

Libbey-Owens-Ford Co. reported lower earnings for the third quarter and first nine months of 1977, but the firm forecasts an 11 per cent increase for the entire year.

Robert G. Wingerter, chairman and chief executive, said the firm's principal markets "showed considerable strength" during the third quarter and that LOF's outlook for the fourth quarter "appeared strong."

He attributed the lower earnings in the quarter to higher than usual startup costs associated with new model automotive glass production. Nine months' earnings were affected by a 17-cent-a share loss on foreign currency translations compared with a 15-cent-a share gain in 1976.

For the third quarter, LOF earned $11.7 million (94 cents a share) on sales of $233.17 million, compared with $12.3 million ($1.02) on sales of $206.9 million in the third quarter of 1976.

Earnings for the nine month period were $43.87 million ($3.63) on sales of $725.98 million, compared with $45.25 million ($3.79) on revenues of $650.97 million a year ago.