A 60-year-old man from Wenatchee, Wash., writes to complain that his employers are pushing him out of his job early, cutting his Social Security payments more than he can afford.

From Houston comes a letter in cramped handwriting from a woman who fears the loss of Civil Service disability payments if President Reagan's proposed changes in the Social Security system are enacted.

The correspondence from a Younkers, N.Y., nursing home resident begins simply, "Help! I need your assistance in my attempt to seek justice."

The letters come from everywhere in the country at a rate of 700 to 800 a week. And they all come to Rep. Claude Pepper (D-Fla.), chairman of the House Select Committee on Aging and perhaps the most dogged congressional champion of the rights of the nation's elderly.

Starting Friday, the answers to such letters will have a public forum, when the 80-year-old veteran legislator begins a second career as a fledgling journalist.

Through an agreement between Pepper and the Newspaper Enterprise Association, a New York-based syndication service, Congress' oldest elected official will inaugurate an advice-to-the-elderly column that will be distributed to 700 newspapers nationawide.

"I have a long and distinguished career in journalism," Pepper said recently with a laugh. "I was editor of the Camp Hill School Radiator [in Camp Hill, Ala.] in 1915. Then I was on the staff of the Crimson and White at the University of Alabama."

But the congressman has no intentio of becoming a retirees' Miss Lonelyhearts. If the questions get too personal, with queries about marrying late seeming to be as spicy as it gets, "We'll tell them maybe they better write Ann Landers or Dear Abby on that one."

As long as he and the select committee were responding to the deluge of mail anyway, Pepper saw the column as way to disseminate more widely the answers. "Instead of writing a letter to Mrs. John Smith of Des Moines, Iowa," he said, "we can give the information to a whole lot of Mrs. John Smiths who might be interested in the same question."

In New York, Barbara McDowell, assistant managing editor of the syndication service, said the column will steer clear of quirky, personal problems and try to answer such common concerns as how Medicare and Social Security benefits work, or where to get help with home repairs.

An exchange from an upcoming column:

Question: I live with my daughter and son-in-law. Several times my son-in-law has come home and beaten me for one reason or another. Other times, he has threatened to throw me out of the house. I have only a small income and cannot afford to move. What can I do?

Answer: Abuse of older people by their families has reached shocking proportions. A survey I made based on statistics from appropriate state agencies indicates that up to 1 million older Americans may be the victims of abuse -- physical, mental or financial. I would suggest that you contact your state department of human services, or its equivalent, and ask for adult protective services. They will look into the problem and arrange for counseling or other appropriate action.

Pepper is not being paid for the column, which he will write or review each week with the help of the staff of the committee on aging. It then will be distributed as part of a package to about 700 daily newspapers from the Rocky Mountain News in Denver to the Westerly Sun in Westerly, R.I., McDowell said.

There is only one restriction on Pepper's new editorial platform.

"If he tried to turn it into a forum for his reelection we would edit that out," McDowell said. "Pepper agrees with us on this. I don't think we'll have any problem.