Comptroller of the Currency, John G. Heimann disassociated himself yesterday from the Carter administration's publicly stated conclusion that his agency's reports exonerated Budget Director Bert Land of all wrong doing.

Heimann was asked at a Senate hearing if Lance was correct when he claimed such exoneration. "That certainly wasn't our assertion," the comptroller replied. He said that was a judgment that he felt he could not make.

Heimann revealed that he has ordered his staff of bank examiners to conduct a nationwide survey to national banks to see how common some questionable banking practices revealed in the Lance affair really are.

"We do not approve" some of those practices, Heimann said, and he suggested that new legislation or regulations might be desirable to prevent their recurrence.

Heimann, dressed in hand-tailored banker's pinstripes, appeared to impress members of the Senate Committee on Governmental Affairs as he answered their questions, mostly from memory and often in specific detail, for nearly four hours. But the new comptroller - he has been the on the job just 57 days, he said - circumspectly dodged repeated senatorial attempts to pass judgement on Lance, who is his colleage in the Carter administration as well as the subject of his office's recent investigations.

The hearings produced new evidence of Lance's difficult financial situation, but it came from Sen. Charles Percy (R-Ill.), not Heimann. Percy revealed that the First National Bank of Chicago recently got Lance to sign over four of his major real estate holdings to the bank as additional collateral on a $3,435 million loan the bank made to Lance in July.

Percy said deeds on this real estate had been recorded just "two days ago" to improve the collateral, which had never been equal to the total loan. Senate sources said Lance had made commitments on four properties as new collateral - has Atlanta mansion (recently put up for sale), his Calhoun, Ga., house, his vacation home in St. Simons, Ga., and another farm in Georgia.

(On July 25 Lance testified to senators that his First Chicago loan was "fully collateralized." The bank's subsequent insistence on additional collateral indicates it disagreed.)

Heimann revealed yesterday that, at the Senate committee's request, bank examiners recently visited First Chicag to evaluate Lance's loan from that bank. The examiners concluded it was a "substandard" loan, Heimann said. This means the loan does not appear sound enough to get a good rating from federal examiners.

Heimann also revealed two new facts about Lance's past dealings with the comptroller's office. One was that federal bank examiners first discovered excessive overdrafts to Lance and his relatives at the First National Bank in Calhoun, Ga., (which Lance ran) in the summer of 1972. By April 1975, examiners referred to these overdrafts as "abusive use of the bank's facilities" by the Lances and Mrs. La Belle Lance's family for their own purposes.

Second, Heimann disclosed new testimony concerning a punitive "agreement" between the comptroller's office and the Calhoun bank aimed at stopping those overdrafts and clearing up other questionable banking practices. It was disclosed that the agreement was rescinded by a regional official despite a warning from the regional counsel that he might be violating official policy.

This episode is already a matter of dispute and official investigation. Donald Tarleton, the Atlanta regional director of the comptroller's office, rescinded this potentially embarrassing agreement last Nov. 22, just hours after Lance visited his office to tell him he would become an important member of the Carter administration. Tarleton claims there was no connection between his action and Lance's visit.

Heimann revealed Yesterday that the lawyer in Tarleton's Atlanta office has testified that he told Tarleton it was his impression that such agreements were supposed to be lifted by the comptroller in Washington, not by the regional office. Tarleton went ahead and lifted in himself.

Heimann indicated a personal belief that some of Lance's past banking practices which were not explicitly illegal were undesirable, and perhaps should be forbidden in the future.He said the new survey of banking practices he has ordered is meant to determine how widespread some of these things are.

Subjects of the survey he said, will include overdrafts by "insiders" (i.e., bank officers and their relatives), loans from banks to the officers of other banks with which the lending bank has "correspondent" relations, and loans from one bank to the officer of another for the purchase of stock in that second bank.

Questions have been raised about all of these in the Lance affair.

Pressed to pass a personal judgment on Lance, Heimann persistently declined. He said at one point that as a banker Lance "built a very successful banking institution," but "his attention to detail clearly leaves something to be desired." On the basis of what he knows now, Heimann said, Lance could still be acceptable to the comptroller's office as the chief executive of a national bank.

On the other hand, Heimann said Lance's behavior was not typical of the banking profession, and he said he would not have written the sort of letter that the acting comptroller in January, Robert Bloom, wrote to the Senate endorsing Lance as "well qualified" to be budget director.

Nonetheless, Heimann said he thought some of the public discussion and press reports on Lance in recent weeks had been personally unfair to him.

In another development, Senate sources said yesterday that investigators from the Government Affairs Committee had taken statements from FBI agents and one or more assistant U.S. attorneys in Atlanta who felt a pending investigation Calhoun bank overdrafts that supported Lance's 1974 campaign for governor was improperly closed last December.

but the man who ordered that inquiry closed - John Stokes, the Republican U.S. attorney at the time - called a press conference for this morning in Atlanta to accuse the Carter administration of withholding damaging information about Lance from the Senate committee that considered his nomination.

Heimann is scheudled to return to the Senate committee for more testimony this morning.

Yesterday, Sen. Bill Roth (R-Del.) said that "relevant information" about Lance was withheld from the committee in January, "and it is incumbent on this committee to determine why the information was not made available to us and who was responsible."