House-Senate conferees voted yesterday to give so-called "small savers" a $2-billion-a-year tax break in 1981 and 1982 by allowing them to escape taxes on part of their income from interest and dividends.

The panel approved an amendment to President Carter's crude oil tax bill that would exempt up to $201 in interest and dividend income for single persons and $400 for couples, beginning next January.

To save money, however, the panel voted to keep the tax break in effect only for two years. A permanent interest and dividend exemption would have cost the Treasury $27 billion over the 11-year life of the crude oil tax, compared to $4.3 billion for the two year trial.

The exemption would apply to interest or dividends from savings accounts, mutual funds, credit unions, certificates of deposit and other forms of investment at banks, thrift institutions and domestic corporations, and to interest on U.S. savings bonds, which ordinarily are taxable.

The provision originally was proposed in a separate House bill as part of an effort to crack down on the use of housing bonds, but was tacked on to the crude oil tax bill by Sen. Lloyd Bentsen (D-Tex.).

Advocates argued the tax break would promote savings and additional investment. However, it was opposed by the Carter administration and the Federal Reserve Board as unlikely to spur either savings or investment.

Under current law, interest income is subject to taxation, while the first hundred dollars of dividend income -- or $200 on a joint return -- currently is exempt.

The action came as the conferees agreed also on a broad plan for dividing up the $227.3 billion in new revenues expected from the crude oil tax between now and 1990 -- a move that was mainly symbolic and will not be binding on Congress or the administration.

The plan would informally tag 25 percent of the total for aid to low-income households, 15 percent for mass transit grants and related programs and the remaining 60 percent for general income tax relief, both for individuals and business.

However, while the crude oil monies would be channeled into a special Treasury account, they would not be formally earmarked. Unless Congress specifically enacts tax cut legislation, the government could use the money for regular spending programs.

Sen. Daniel P. Moynihan (D-N.Y.) summarized the impact of the plan by telling his colleagues on the panel, "We're not doing anything very serious here today, we all know." Nevertheless, the election-minded lawmakers rushed the proposal through.

Agreement on the broad allocation formula marked the last major hurdle before formal approval of the crude oil tax bill, which has been bogged down in conference since late December. The committee still has several minor provisions to hammer out before finishing its work.

The conferees also agreed yesterday on a compromise plan of new tax breaks for gasohol producers, designed to please midwestern grain farmers. The provisions would add $1.8 billion to the government subsidies the gasohol industry already enjoys.

The vagueness of the broad distribution formula reflected the continuing inability of the conferees to agree on how to spend the crude oil money.The panel pushed off specifics of the low-income assistance plan and a tax credit for home heating oil costs for separate legislation later.

The plan for distributing the $227.3 billion in crude oil tax monies differed significantly from that proposed by President Carter, who had hoped to use the proceeds to finance a crash program to develop synthetic fuels.