House Senate energy tax conferees met for the first time in seven months yesterday and agreed it was time to resume their search for a mutually acceptable bill. But then they adjourned without taking action.

Their meeting was staged at least in part as a pep rally to send president Carter off to the economic summit meeting in Bonn with an indication that his long-stalled energy bill is alive and soon to be passed. But no one suggested that the proposed tax on domestic crude oil - which is the centerpiece of his energy plan - can be enacted.

Senate Finance Committee Chairman Russell B. Long (D-La.), who had insisted last year that the tax conference wait for agreement by other conferees on natural gas pricing, did say that, now that the gas conferees have reached agreement, he is ready to sit down and seek a tax compromise. However, no final decision on taxes is expected until Congress votes on the compromise to life federal price controls from newly discovered natural gas by 1985, and that may not come until the end of summer.

After a series of brief remarks by leading conferees, Chairman Al Ullman (D-Ore.), adjourned the conference, saying he would reconvene it in the near future to start making some decisions on taxes.

Ullman opened the meeting with a reminder that the President had just departed for Bonn for a meeting with trading partners who are concerned whether the United States can develop a national energy policy. Less imported oil would mean a stronger dollar abroad and a better market for foreign products in this country.

Ullman, who strongly favors Carter's proposed domestic crude oil tax to cut consumption by raising prices, said that if the tax is not enacted Carter would have no choice but to take administrative action - import fees for quotas. These alternatives are "very forbidding," he said.

The Senate rejected the crude oil tax last year - although Long personnally supported it provided at least part of the revenue was returned to producers as incentives to encourage more production. Carter wanted to rebate all the revenue to the public.

Yesterday Long said that now that the natural gas conferees have reached agreement," the time has come when we should start to make progress." The nation needs a "constructive, imaginative compromise" on energy taxes, he said.

Rep. Thomas L. Ashley (D-Ohio), chief House Coordinator of the complex energy package, noted that while nontax conferees have agreed on four other parts of the package, the tax part is more important than all the rest put together so far as saving oil is concerned.

The crude oil tax would push the price of domestic oil up to the world price in three annual steps. The other major tax proposed by Carter would be imposed on industrial users of oil an natural gas to encourage use of coal. The House and Senate passed different versions of this tax. The tax conferees have not taken any votes on either tax.

The conferes have approved a bobtailed version of Carter's tax on the sale of gas-guzzling cars, but only if the deadlocked nontax conferees drop a Senate ban on sale of gas guzzlers. The tax conferees have approved tax credits for home insulation and installation of solor heat.

Today the Senate is expected to try to give Carter a little more encouragement at the summit by approving the first of the conference agreements. This is a regulatory bill requiring untilities and industrial plants to switch from oil to coal, provided it is available and would not violate environmental laws or court orders.