Federal inspectors, whose pass-or-fail grades can ground anything from a package of chicken wings to a jumbo jet, often complain that they get in trouble when they do their jobs too well.

"Too well" can mean issuance of a warning, fine or closure order for an unsanitary meat packing plant, or health and safety violations that can cost big business time and money.

If inspectors are backed up by their agencies when tangling with the people they are paid to inspect, things go smoothly. Sometimes, the inspectors say, their government bosses side with businessmen and firms who claim they are being unfairly harassed by the inspectors.

In a major case, the Merit Systems Protection Board temporarily has barred the Labor Department from firing one of its Mine Safety and Health Administration inspectors in Wheeling, W. Va. The man claimed he was canned for doing his job too well, despite pressure from bosses to ease up. The MSHA says he was overzealous.

After a series of running battles with major coal mine owners in his area -- $20,000 in fines and a 12-for-14 record in court -- the department fired inspector Charles B. Coffield Charges were "unacceptable and inexcusable activities and statements" despite an eight-year record, with outstanding, work citations and a letter from the agency head commending him for saving the lies of three boys trapped in a New Cumberland mine in mid-1979.

Coffield, who earns about $29,000 a year inspecting mines, went to the Office of the Special Counsel. It, along with the MSPB, was created by President Carter's civil service reform act to provide protection to federal whistle blowers and prevent reprisals against them.

The Office of Special Counsel said after an on-site investigation, decided the man had been fired improperly. It recommended he be restored to duty pending a final report.

MSPB agreed. Coffield was reinstated after two weeks off the job.

The Labor Department has made it clear it plans to make the firing stick. It disagreed with a Coffield decision to shut down a portion of a mine because of coal dust buildup that he said could cause an explosion, and his judgment that a piece of mining equipment was unsafe despite its clearance by the Mine Safety Health Adminstration.

(The Office of Special Counsel said Coffield previously had warned the mine operators to clean up the coal dust, and that there have been deaths in mines this year involving the same kind of equipment Coffield rejected as unsafe).

MSPB, which doesn't always go along with the often bulldog-like attacks of its Office of Special Counsel, did so this time. It has ordered the Labor Department to keep Coffield on the payroll for at least 60 days while the investigation into his case, his allegations and Labor counter-claims, is completed.

MSPB has been accused in the past of being too soft on government agencies, not tough enough protecting individual employe rights. It is hanging tough here, protecting a man's job while he fights city hall. The board said that while Labor claims that the special counsel's petition was based on "numerous inaccuracies" Labor failed to say what, if anything, is inaccurate.

The case is not closed, nor prehudged, MSPB's action, in effect, is a stay of execution until the evidence is in.

It may be the government is correct and the coal companies are correct and this fellow, Coffield, is too much of a nose-to-the-grindstone type. On the other hand if you have spent any time in a coal mine, it is hard to justify being too careful.

Whether you are strapping yourself in an airplane seat, about to bite into a hot dog, or preparing to take a tummy tranquilizer, it is sometimes nice to know that the federal inspector who okayed the product is, maybe, just a bit of an S.O.B.