Facet Enterprises Inc. is about as modest and obscure an enterprise as any company listed on the New York Stock Exchange can be.

It is a six-year-old manufacturer of industrial filters, valves, auto parts and orthodontic adhesives. Based in Tulsa, Facet has plants in eight states, with 2,500 employes. The company reported earnings of $233,000 on sales of $32.8 million in the quarter that ended Dec. 31, its first quarterly profit since 1978. Facet stock sells for about $5.75 a share.

Yet this little-known company has the potential to make a large impact on the industrial scene, through a lawsuit against the federally sponsored Pension Benefit Guaranty Corp. (PBGC) that could make a shambles of the entire pension-insurance structure in private industry.

Facet was created by order of the Federal Trade Commission. In an antitrust case, the FTC ordered Bendix to establish the company and then spin it off, which it did--endowing its offspring with factories, executives, staff and pension obligations toward former Bendix workers. Now Facet is trying to shut down the underfunded pension plan it inherited, transfer its liabilities to the PBGC, and start over with a more modest plan that it says it can afford.

But the PBGC says that if Facet is allowed to terminate its old plan, every other company with underfunded pensions could try to do the same thing, unloading billions of dollars in pension liabilities on the PBGC and forcing Congress to bail out the pension-insurance system.

Facet, claiming that its pension plan is so expensive it could bankrupt the company, says the federal government should help to solve a problem it created--especially because the purpose of the FTC's order was to create a competitive company. But the PBGC, created by Congress in 1974 to provide the same protection for pension plans that the Federal Deposit Insurance Corp. does for bank accounts, says the companies that pay obligatory premiums for its coverage should not have to bear the burden of the unfavorable terms on which Bendix spun off Facet.

"If they can do this," said PBGC executive director Robert E. Nagle, "there are a lot of companies out there that would love to transfer their unfunded liability to us." He said the 1974 Employee Retirement Income Security Act does permit the termination of pension plans and the transfer of their obligations to the PBGC, "but most of those that come to us are from bankrupt or closed operations." What Facet wants to do, he said, is like a bank failing to repay its depositors and forcing the FDIC to cover their accounts, and then resuming business as usual with new accounts.

He said the PBGC "agonized" over Facet's problem before rejecting its proposal on the grounds that "if we allowed Facet to do this, other companies would want to do it." But he acknowledged that if the PBGC loses the lawsuit Facet has filed in federal court in Tulsa the effect would be the same, setting a precedent for other firms, and "we will have to go back to Congress to rewrite the legislation."

Facet's situation is analogous to that of the District of Columbia government, which at the time of home rule in 1975 acquired more than 20,000 employes who had previously been on the federal payroll and covered by the federal government's pension plan. The city inherited the workers and their pension rights, but the fund set up to cover future pension payments was insufficient to meet the growing obligations. The city is still trying to persuade Congress to make the plan whole.

"We did not create this problem and it is not a result of mismanagement," Facet President James R. Malone said in an interview. "We are not asking for a bailout. We have followed the law. All we say is that if the federal government was responsible for setting up a company that was supposed to be competitive, they ought to take some responsibility for this."

Malone was interviewed during one of his frequent visits to Washington to lobby for enactment of a bill that would allow Facet to declare its old pension plan terminated, despite the PBGC's opposition. The bill, sponsored by Sens. Carl Levin (D-Mich.), David Boren (D-Okla.), Alphonse D'Amato (R-N.Y) and Daniel P. Moynihan (D-N.Y.), is bottled up in the Labor and Human Resources Committee, where no action is imminent.

Facet executives make no secret of their frustration at being unable to solve a problem they did not create, especially because their proposal to terminate the old pension plan and start from scratch with a new one has been accepted by the United Auto Workers Union, which represents Facet employes.

"The PBGC has simply refused to give Facet fair treatment," Malone said in a letter to Rep. James J.Blanchard (D-Mich.). "Arbitrary pronouncements are being substituted for directly applicable provisions of law. The pertinent facts are being ignored, and we are being treated as though our purpose is to milk the U.S. Treasury rather than to save Facet . . . I infer that the PBGC's objective is to force Facet into insolvency or bankruptcy" before allowing termination of the pension plan.

At its birth in 1976, Facet assumed vested pension liabilities of approximately $70 million, and Bendix transferred pension trust assets valued at only $18 million. According to Facet Chairman James B. Treacy, "although the FTC had jurisdiction of the divestiture process, it competely ignored the pension matter."

Facet executives anticipated the pension problem, but until the day the company was formally spun off they were still employes of Bendix and unable to challenge the parent company. After divestiture, Facet complained to the Internal Revenue Service, which ordered Bendix to put up another $14.7 million for Facet's pension fund. Then Facet sued Bendix.

Facet recognized that it had a weak case under existing law. As Treacy put it, "the complaint was based on an untested and uncertain legal theory--that Bendix and its officers owed Facet certain fiduciary and other legal duties at the time when Facet was a wholly owned subsidiary of Bendix."

Facing a long, expensive legal case it was not certain to win, Facet accepted a settlement with Bendix in 1980. Bendix put up another $4.3 million for Facet's pension plan and dropped its appeal of the earlier IRS ruling. Facet executives welcomed the agreement, which they said was the best they could get under the circumstances, but it still left more than $30 million in "asset insufficiency" in the pension fund.

On the theory that most of those covered by the plan were retirees and never actually worked for Facet, the company sought to declare that plan legally terminated and replace it with a fully funded new plan covering current workers. The PBGC would have had to assume the obligations of the terminated plan, and it refused to do so.

PBGC's Nagle told Facet's lawyer, John M. Vine of Covington & Burling, that the termination was a ruse to get the PBGC to "subsidize" a pension plan that was in fact continuing.

He said the PBGC knew of "over 20 very large firms" whose unfunded pension liabilities are about $6 billion "and whose financial difficulties would undoubtedly make tempting the adoption of arrangements similiar to those you are proposing . . . . Thus, the consequences of our acceptance of the type of proposal you are advancing could be either a huge shift of pension costs to PBGC's premium payers, or the total collapse of the insurance system."

With the legislation pending, the lawsuit working its way through federal court, and no negotiations in prospect, Facet is obliged to keep meeting its obligations under the current pension plan, which is depressing its earnings and stock value and, according to its executives, threatening to bankrupt the company. Without the pension burden, they say, Facet could fulfill the task for which the FTC ordered it created, competing profitably in the marketplace.