Ford Motor Co. said yesterday it lost a record $164 million in the first quarter and warned losses would increase before beginning to narrow later in the year.

Ford earned a record $595 million ($4.97 a share) in the comparable 1979 quarter.

The loss -- which was more than industry analysts had expected -- was the result of a profit outside the United States of $309 million combined with a United States loss of $473 million.

The U.S. loss is almost as large as some predictions of the deficit to be reported worldwide by struggling Chrysler Corp. for the first three months of the year.

Revenues for the quarter were $9.61 billion, a 24 percent drop from $12.6 billion in the 1979 period.

Worldwide vehicle sales of 1.24 million units were off 31 percent from 1.80 million in the same period last year.

Unit sales in the United States werre down 45 percent, while unit sales outside the United States were down 12 percent

Ford earned $220 million ($1.83) from domestic operations in last year'-quarter, while foreign business produced profits of $375 million ($3.14). y

Chairman Phillip Caldwell and President Donald E. Petersen said in a statement that the company lost money because of lower volume, increased marketing costs, a larger number of small vehicles in the product mix and the impact of inflation. Small vehicles generally carry smaller profit margins.

Ford hasn't suffered this large a loss in any quarter since 1967, when it lost $109 million worldwide in the fourth quarter. Its previous record loss from domestic business was $299 million in the 1979 third quarter.

The company's statement said things will get worse this year before they get better. High interest rates and energy costs, a weakening economy and energy costs, a weakening economy and "other factors" are "expected to aggravate Ford's losses at least the near term," the statement said.

"That 'aggravate' is a key word," observed Arvid Jouppi, head of research for the brokerage firm of John Muir & Co. "It means they'll go into the second half with a loss of about $350 million to make up in the third and fourth quarters -- which they can do, but it will mean earnings for the year of about $2 a share and a cut in the dividend from $1 per quarter to about 50 cents."

Jouppi said he had expected a loss of $90 million (75 cents) in the most recent quarter.

Ford is the third U.S. automaker to report first-quarter results. General Motors Corp. profits fell 85 percent to $155 million from the previous year's first quarter, and American Motors Corp. earnings declined 96 percent to $1.2 million.

The British tax treaty gave Ford refunds of half the taxes paid on its behalf in Britain since 1975. Before the treaty, Britian, to avoid double taxation of profits, gave refunds to British shareholders for taxes paid on their behalf by the companies. Overseas shareholders couldn't get refunds. Under the treaty, overseas shareholders now get a refund for half the amount.

PepsiCo Inc., a soft drink company, reported that first-quarter earnings rose 5.3 percent to $47.6 million despite a decline in earnings from its beverage division.

PepsiCo said earnings amounted to 52 cents a share for the quarter ended March 22 compared with $45.2 million (48 cents) last year as revenues rose to $1.18 billion from $1.01 billion.

The company said earnings from its beverage division were down 9 percent largely because profits were unusually high last year when bottlers were stocking up on soft-drink concentrate in advance of a Teamsters strike.

PepsiCo said its other divisions all reported higher sales and earnings. The food service segment, which includes the Pizza Hut and Taco Bell restaurant chains, reported a profit gain of 33 percent on a sales boost of 13 percent.

Allied Chemical Corp. will spend almost $2 billion over the next five years on oil and gas exploration and development, Chairman Edward E. Hennessy Jr. said yesterday.

The anticipated expenditure is more than twice what was spent on oil and gas exloration in the past 10 years, he told the company's 60th annual stockholders meeting in Morris Township, N.J.

Hennessy announced record first-quarter net income of $68.3 million ($2.36 a share), an increase of 145 percent from $27.9 million (98 cents) a year ago. Sales rose 64 percent to $1.384 billion from $844.7 million in the 1979 first quarter.

Allied's board of directors voted to increase it quarterly dividend from 50 to 55 cents a share.

Hennessy, who became chief executive officer last May, said the strong first-quarter performance was the result of significantly improved sales and earnings from North Sea oil, Indonesian natural gas, domestic gas and oil products, soda ash, high-density polyethylene and fertilizers.

The financial picture for Allied listed as No.69 in the Fortune 500 list of industrial corporations, will improve because of the divestiture of several unprofitable businesses.

The company still is attempting to sell its Ashland, Ky., coke plant, which lost $4.5 million before taxes during the first quarter.

Hennessy said the firm is considering a name change to refect it move away from the chemical industry, but he declined to say when this could occur.