The growing number of bad farm debts and loan delinquencies suddenly is shaping up as a major new and urgent issue for Congress and the administration as work continues on a new farm bill.

The sense of urgency was underlined last week by Donald Wilkinson, chief federal regulator of the independent Farm Credit System, who disclosed that the FCS would need "multibillions" of federal aid within the next 24 months to survive.

Farm-state legislators, relieved that Wilkinson finally went public with the system's bad-debt problems, have been quick to rally around the idea of some kind of federal aid to keep the FCS alive -- and to shore up other parts of the private and government farm-loan network.

The farmer-owned cooperative FCS holds slightly more than one-third of the country's $214 billion farm debt. Another one-third is held by commercial banks, and the remainder is held by the Farmers Home Administration (FmHA) and by institutional and private lenders.

Anxieties over credit problems have been heightened by the prospect of huge harvests this fall, further depressing farm prices, along with the ongoing decline in land values and lower exports -- all factors making it harder for farmers to pay off debts.

Senate Majority Leader Robert J. Dole (R-Kan.), calling for Senate hearings on the credit issue, said "there is no doubt in my mind that the farm credit system is in need of a major overhaul and possible restructuring . . . We could be looking at up to $50 billion in nonperforming loans over the next year or two."

Added Rep. E (Kika) de la Garza (D-Tex.), chairman of the House Agriculture Committee: "I believe the Farm Credit System is so important to American agriculture that Congress will not want to stand by and watch it, or large segments of it, collapse."

But Congress first must identify the problem clearly and then decide how to deal with it, he continued.

A House Agriculture credit subcommittee began a series of hearings on troubles in the Farm Credit System this week, and early testimony indicated the debate over a federal bailout could be long and heated.

Reps. Jim Leach (R-Iowa) and Jim Slattery (D-Kan.), for example, cautioned that aid to the FCS should not become a cover for bailing out Wall Street investors who buy the bonds that finance the system. Reps. Cooper Evans (R-Iowa) and Bill Schuette (R-Mich.) called for federal guarantees and more federal regulatory oversight of the system. Others urged different approaches.

Chairman Ed Jones (D-Tenn.) said that future witnesses will include FCS officials and members of the Reagan administration, which for weeks has been reviewing federal aid options privately while insisting publicly that the credit system must use its own resources before seeking government help.

Last week's statement by Wilkinson, governor of the federal Farm Credit Administration, was the signal that the system can not go much further without undefined federal assistance.

In the Senate, Chairman Jesse Early testimony at hearings on troubles in the Farm Credit System indicated the debate over a federal bailout could be long and heated. Helms (R-N.C.) said that his Agriculture Committee will begin similar hearings as soon as a Farm Credit System task force completes a package of aid recommendations, probably by the end of this month.

Helms warned, however, that "the worst thing we could do would be to allow the problem to become a political football . . . It is not a Republican or Democratic or administration problem -- it is a problem facing all of agriculture and the country."

Rep. Ron Marlenee (R-Mont.), a ranking member of the House committee, added a sobering footnote as he urged an impartial approach: "Either we address this problem in a nonpartisan cooperative spirit, or within six to eight months we will see the damndest crash in real estate values that this nation has ever experienced."