The Senate Finance Committee yesterday approved a scaled-back proposal to exempt more oil from President Carter's "windfall profits" tax, but only after rejecting two far larger oil-industry breaks.

The action, which constituted a setback for portions of the oil lobby, came after moderate Republicans balked at endorsing the larger exemptions for fear of running out of room to tack on tax credits for homeowners.

The skirmish marked the first round in a dispute within the panel over how to apportion both the tax and the various credits -- a fight pitting senators from oil-producing states against those from other regions.

Yesterday's exemption would apply only to the first 1,000 barrels of oil a day produced from stripper wells operated by small, independent drillers -- a move that would trim the tax measure's 10-year take by $7.7 billion.

The committee also plans to consider a proposal by Sen. Mike Gravel (D-Alaska) that would exempt Alaskan oil from the windfall profits tax -- a move that would slash the 10-year revenue gain by $12 billion.

The exemption approved by the panel yesterday also would apply to the portion of oil revenues that go to landowners, such as farmers, to whom oil drillers pay royalties for use of their land.

The rejected proposal by Boren would have exempted all oil from stripper wells, those that produce fewer than 10 barrels a day over a year. Stripper wells are now exempt from price controls. Bentsen's amendment would have exempted several large categories of oil, including newly discovered oil, new increments of hard-to-drill "tertiary" oil and heavy oil, found mostly in California.

Earlier, the panel rejected proposals that would have exempted all oil recovered from stripper wells or produced by small, independent driers. Those measures together would have trimmed the tax by $47.4 billion.

The broader exemptions, proposed separately by Sens. David L. Boren (D-Okla.) and Lloyd Bensten (D-Tex.), were backed solidly by oil-state senators, but defeated 12 to 6 and 11 to 7, respectively -- close votes for the Finance panel.

Senators from oil-consuming states are planning to propose amendments providing tax credits for homeowners and business and relief for users of home heating oil, and want room in the tax bill to finance these plans.

With yesterday's action included, the Finance panel has trimmed the amount of new revenues the windfall tax would raise over the next 10 years from $104 billion in the House bill to $71.8 billion.

Some $99 billion in tax credit the committee approved last week have been rescinded and will be reconsidered in substantially pared-back form later this week or early next week.