Since it was founded by a sea captain in 1914, Mariners Savings and Loan has done business quietly and cautiously, operating just 90 minutes a week collecting savings and making home loans to families in ethnic East Baltimore. It is one of scores of old-style, small-time thrifts, largely forgotten in the whirlwind of Maryland's savings and loan crisis.

In trying to solve the troubles that struck the larger institutions, however, the state has placed the fate of many of these little thrifts in doubt.

Most of these institutions were previously insured by the Maryland Savings-Share Insurance Corp., which was dissolved during the spring. Now, under legislation approved by the General Assembly, thrifts with less than $15 million in assets have until 1989 to gain federal insurance or merge with federally insured institutions.

If unable to meet the requirements for federal insurance or unwilling to merge and lose control of the thrift, the small savings associations will be forced to go out of business.

"It's fairly unfortunate. They're having to pay the penalty for the high-flying, fast-growing institutions," said Charles Kresslein, president of the Maryland League of Financial Institutions, a trade association for the state's thrifts.

Kresslein and others agree that most of the small institutions are financially healthy. They generally limit their services to home loans and savings, as thrifts were originally intended to do, and present little risk to insurers. All but a handful have been allowed to operate normally since the crisis and have not been subject to an order by Gov. Harry Hughes limiting withdrawals to $1,000 a month.

"They're not involved in the kind of things that Old Court and Merritt were involved in," said Kresslein, referring to high-risk real estate ventures pursued by the two institutions, which were placed under conservatorship as the current crisis unfolded.

Of 67 institutions with less than $15 million in assets, 11 have been granted federal insurance, and eight have received conditional approval, according to officials at the newly created state insurance fund. Federal insurance requires associations to meet a number of requirements, including assets worth 5 percent of liabilities and daily business operations, from a ground-floor location.

A few of these institutions have merged, but most, said Kresslein, "are not doing anything. They're going to buy some time."

"We're just sitting tight to see what's going to happen," said Mariners President William H. Eagers.

His hope is that legislation will be approved to extend the life of the Maryland Deposit Insurance Fund -- now set to go out of business in four years -- to continue the insurance coverage it now offers for most of the smaller thrifts.

The cause has been taken up by state Sen. Joseph S. Bonvegna (D-Baltimore) who, with Senate President Melvin A. Steinberg (D-Baltimore County), recently met with directors of the small thrifts. Bonvegna said, if necessary, he will introduce legislation to keep the associations open.

But Kresslein believes it is unlikely that legislators outside the Baltimore area, where many of the small, ethnic thrifts are located, will be sympathetic. "The comment has been made . . . how many times does the state have to be burned," he said.

Unlike their high-flying brothers, the smaller savings and loans have changed little since their beginnings.

Kosciuszko Permanent, for example, was opened in 1894 by Polish immigrants to help fellow settlers who couldn't get credit at the banks. Ninety-two years later, said President Peter Kutz, many of the transactions are still conducted in Polish. Kutz said his association has received conditional approval for federal insurance.

An association with Czechoslovakian roots, Slovan Building and Loan, is losing its name but gaining a partner in response to the new legislation. Association attorney Anthony J. Brozik said the 60-year-old Slovan would merge with Western Permanent Savings and Loan within two weeks.

But at Mariners, "it's business as usual," said Eagers. There are no plans to merge or apply for insurance from the Federal Savings and Loan Insurance Corp., whose requirement for regular business hours conflicts with Mariners' lighter schedule; it's open Thursday nights only, 7 to 8:30.

"I've been in the business for probably 30 years, and my father 50 years before me," said Eagers. "The association has been around for 70 some years. We'd like to continue."