Most American bankers surveyed this week believe that the U.S. banking system would not be endangered if President Carter's freeze on Iranian assets were lifted.

Even if the Iranians were allowed to reclaim the bulk of their assets immediately, which is considered highly unlikely, and were to remove them from U.S. banks at once, there would be no serious danger to the banks, to the dollar or to money markets, the bankers said.

One official of a major bank with Iranian interests said the large banks with huge total deposits hold the biggest Iranian accounts, but they also are better able to cope with a large withdrawal of deposits. If the Iranians withdraw their money from his bank, "It would not be more than a wrinkle," he said.

Another banker, who like most of those interviewed wished to remain anonymous, explained that it is not really possible for the Iranians to take their money out of the international banking system. "All funds are fungible" and will be redeposited into U.S. banks if pulled out by the Iranians and placed in overseas banks, he said.

The Treasury estimated last November that more the $8 billion worth of assets were frozen in U.S. banks at home and overseas. Of this total, more than $4 billion were thought to be in foreign branches of U.S. banks, $1.2 billion in U.S. government securities and $600 million in gold (now worth nearly $1 billion) were being held in the New York Federal Reserve bank, and the rest was in domestic branches of U.S. banks.

Chase Manhatten probably has the largest deposits of Iranian money, followed by Bank of America, Citibank, and Morgan Guaranty. Both Chase Manhatten and Bank of America have large loans outstanding to the Iranian government and sizable Iranian assets deposited with them. There is some confusion over whether the banks may offset these loans against some of the Iranian dollars deposited with them.

One banker said that it would be "political suicide" if the administration attempted to force banks to return money to Iran without some assurance that the Iranian government would honor its debts. If any bank lost money through carrying out an executive order, it probably would sue the administration, he said.

Although the bank regulatory agencies have not had authority to propose contigency planning for the banks holding Iranian assets, the agencies believe that the banks themselves have made such provisions.

A Federal Reserve official said that the amounts of U.S Treasury debt and gold owned by the Iranians and frozen would not be enough to shake the markets for government securities or gold if they were released and all sold at once.

There are extremely complicated, legal disputes over the money in commercial banks.Bankers are most worried that their claims, and those of U.S. companies, against the Iranian government will not be met if the administration rushes through measures to unfreeze all the Iranian assests held in the U.S.

But they generally believe that even if he wanted to, the president could not overrule the courts, which now are considering disputes over the assets. News from Iran yesterday suggested that even the Iranian government does not expect the United States to overrule suits now in the courts.