Sen. Jesse Helms (R-N.C.) raised new questions yesterday about the Reagan administration's nominees for two high State Department posts, but he agreed to early Senate votes on their confirmation.

Helms demanded that the Senate Foreign Relations Committee recall Myer Rashish, nominated to be undersecretary of state for economic affairs, to hear Rashish's views on the sale of Caterpiller Tractor Co. pipelaying equipment to the Soviet Union.

The committee agreed to such a hearing, and Helms in turn agreed to a Senate vote on Rashish's nomination within two days after the hearing.

The Carter administration last November approved a license for a $1 billion Caterpillar sale of pipelaying equipment to the Soviets. Since then, the Soviets have scaled some of its purposes, requiring a reconsideration, which is not yet completed, within the U.S. government.

Helms said Rashish had recommended that 100 Caterpiller pipelayers be sold to the Soviets and called this "highly inappropriate." Rashish could not be reached for comment.

Helms also sought a new delay in Senate action on the nomination of Chester A. Crocker to be assistant secretary of state for African affairs, accusing Crocker of leaking government secrets. However, Senate Majority Leader Howard H. Baker Jr. (R-Tenn.) would not permit Helms to interpose a new barrier to Crocker's confirmation, and Helms agreed to an immediate vote.

The vote was delayed until this afternoon because Sen. Paul E. Tsongas (D-Mass.), who backed Crocker's nomination in the Foreign Relations Committee, insisted on a roll call.

Rashish and Crocker were unanimously approved by the Foreign Relations Committee April 28. Helms who opposed their nominations but did not participate in the vote, placed "holds" the next day on consideration of their confirmation by the full Senate.

Baker decided last week to move ahead despite Helms' position.Baker announced last Thursday, in what he and Helms now say was a misunderstanding, that Helms had dropped his "hold."

Helms earlier had been urging the administration to place a Boston researcher, Clifford A. Kiracofe Jr., in charge of U.S. policy toward southern Africa in exchange for lifting his "hold" on the Crocker confirmation. Helms told reporters yesterday that, on the basis of a private meeting with Crocker last Thursday, "I think you'll find Kiracofe participating in the formulation of policy" in the region.

Helms, in a Senate speech, charged that Crocker was responsible for recent leaks of confidential information about U.S. policy in southern Africa. However, most of the leaks, which are under investigation by the State Department, appeared to be attempts to embarrass Crocker and block the policies on southern Africa set forth in recent weeks by the administration.

Crocker had no comment on Helms' charges except to say that the leaks are under investigation.