The Senate rejected, 51 to 30, an attempt to bury its puny energy tax bill yesterday and appeared about ready to send it to conference to try to work out its substantial differences with the House.

The defeated motion to send it back to committee for burial was supported by an unusual coalition: liberals who view the bill as simply a multibillion-dollar tax incentive giveaway to industry, and conservatives who see it as a vehicle for rescuing President Carter's crude oil tax in conference.

Russell B. Long (D-La.), chairman of the Senate Finance Committee and floor manager of the bill, said Carter has asked that the bill be passed and sent to conference to strengthen it.

The House has approved Carter's three proposed oil-saving taxes - on the price of crude oil, on industrial use of oil and natural gas, and on purchases of gasoline-guzzling cars. Long's committee rejected all three taxes and converted the bill into a package of $40 billion in tax credits to the oil and other industries by 1985 to encourage more production and conservation of oil and conversion of plants to use of more abundant coal.

The full Senate restored a modified version of the industrial use tax, which is expected to be the big oil saver in Carter's program. Sponsors said the amendment that was adopted would save about 1.2 million barrels of oil a day by 1935.

When Long failed to win committee approval of the Carter crude oil tax, he permitted the committee to load the bill up with the tax credits, which members estimate would lead to savings of more than 20 million barrels a day by 1985.

Now Long's plan is to go to conference and agree to some form of the crude oil tax in return for House approval of some of his credits.

Yesterday the Senate rejected attempts to knock out a $3-per-barrel tax credit to encourage production of oil from shale and a credit of 50 cents per thousand cubic foot for hard-to-reach natural gas.

The Senate on Thursday preserved $1 billion in tax revenue by knocking out a tax credit to Greyhound and other intercity bus lines. But it more than offset that by voting a $75 annual tax credit to each person over age 65 to help pay the higher costs of energy.

Approved by the Senate was an amendment saying that, if a crude oil tax is enacted, $400 million a year of its revenue for the next four years would be handed back to the states for road repairs. The states are expected to receive less highway revenue from their gasoline taxes as the energy program reduces auto travel.

Meanwhile, conferees on non-tax parts of the energy package reached an impasse on the Senate's proposal to ban sale of gas-guzzling cars after 1979. They broke up for the weekend hoping their staffs can find some common ground by Monday.

House conferees voted unanimously to reject the ban, on grounds that it would save very little oil and that big families should be permitted to buy a big car if they can afford and need one. The senators voted unanimously to insist on the ban on big inefficient cars, on grounds that the rich should not be able to avoid the sacrifice demanded of all by the energy problem.