September 1, 1983

Prices farmers get for raw products climbed 4.6 percent in August, the sharpest single-month increase in more than three years, the Department of Agriculture said today. Drought throughout the major crop areas and the Government's payment-in-kind acreage program have curtailed harvest prospects sharply this year, helping to drive up market prices of key commodities. Under the payment-in-kind program, the Government repays farmers for idling land with surplus crops.

A thumb-sized plastic knob for the cockpit of the Navy's A-7 jet fighter can cost $400. A tiny machine screw for the Minuteman 2 missile can cost $36.77. A ring seal used in the engine of B-52 bombers can cost $2,020.50. And the Navy paid $435 for an ordinary hammer. Selling spare parts to the military is a $13 billion-a-year business that Pentagon officials and defense-industry executives say is almost impossible to control. Perhaps more than in any other area of military purchasing, spare parts tend to be sold at huge markups under contracts that are signed without competitive bidding by manufacturers who are rewarded even if they deliver their products late. But because the Defense Department buys them in small quantities and because they typically account for only a small fraction of a contractor's total sales, spare parts are rarely subject to close scrutiny. Officials say this means that rapid price increases are rarely challenged.

MORE divorced and separated men are delinquent in making child- support payments than ever before, and it is a phenomenon that social scientists are trying to explain, legislators are trying to remedy and national women's and men's organizations are disagreeing about. Just 46.7 percent of four million American women who were supposed to receive child-support payments are collecting the full amount, the Census Bureau reported recently. The number of delinquents was put at 2.13 million, 380,000 more than when a similar survey was conducted in 1978. ''The reasons these men didn't pay are complex and hard to pin down,'' said Ruth Sanders of the bureau's population division, who compiled the report. ''The reasons may range from not wanting to pay to the possibility that men who see their children less often start paying less. It may reflect the lack of court enforcement or men's financial situation.''

Plans by New York City's private hospitals and medical centers to spend more than $4 billion on renovations and new technology should be drastically cut, the city's federally financed health planning agency advised Governor Cuomo yesterday. The unit, the New York City Health Systems Agency, described the projected costs as ''staggering by any standard'' and ''unaffordable.'' It warned that they would have to be borne by the taxpayers and that they would be damaging for the hospitals themselves, especially those in impoverished neighborhoods. The state regulates all new construction in hospitals, private as well as public, on the ground that public funds, in the form of Federal and private insurance plans, pay for virtually all hospital construction. The New York State Department of Health is now seeking to extend that authority.

The Economy Leading economic indicators rose just 0.3 percent in July, the smallest of 11 consecutive monthly gains, the Commerce Department reported. The figure suggests that the recovery's strong pace, which was worrying many economists, is slowing down. With slower growth, experts said, interest rates might recede a bit. But they cautioned against putting too much importance in a one-month change in the index. (Page A1.) Prices farmers get for raw products climbed 4.6 percent in August, the sharpest such increase in more than three years, the Agriculture Department reported. The increase, after two months of declines, was linked to widespread drought and the payment-in-kind acreage program, both of which are squeezing supplies. (D1.)