Bo Schembechler carries with him the aura of a man who is living out a dangerous parable, one which is singularly and frighteningly American.

The Michigan football coach had a major heart attack in 1969 and quadruple-bypass open-heart surgery in 1976. Yet he remains at one of the most ruthless, quixotic and arduous jobs imaginable -- boss of a football machine that, until this season, had finished in the top 10 for 10 straight years.

On the one hand, Schembechler, 50, is the emblem of vigor, success and don't-tread-on-me humor -- a man who is famous, powerful and at a prime age within his chosen world.

With his wound-tight intensity, workaholic habits, intransigent perfectionist habits, hurry-up eating style and erratic exercise schedule, Schembechler is also a casebook example of a man walking a tightrope.

His health history might as well have "Uncle Sam" stamped on the cover.

On top of everything else, the football wars seem determined to test Schembechler's patience and easily ruffled calm as much as they have any coach in history.

Seven times in his 11 years at Ann Arbor Schembechler has taken Michigan to a bowl game, and all seven times he has lost -- always by one touchdown or less. Friday's 17-15 upset at the hands of North Carolina in the Gator Bowl here was the latest indignity.

Every year Michigan is excellent -- as must be a school that once mailed out a million season-ticket flyers. And, every year, Schembechler ends on a bitter final note: 0-10-1.

Perhaps only great success, like Schembechler's 104-9-3 record in games other than season-enders, can lay the groundwork for equally dramatic failure.

"I feel sorry for two people -- me and Bo," said Michigan All-American tackle Curtis Greer. "This (end-of-year) losing streak is getting to be a big thing with him."

Schembechler's precarious health ought to force him toward a sensible life style.Yet Michigan Stadium has more than 100,000 seats and every one has been sold out for 70 consecutive games. Schembechler is the most essential man in a multimillion-dollar athletic empire. Like the strong man at the bottom of a human pyramid, he feels the full weight of all the people who prosper by standing on his shoulder. How can he say, "I quit"?

"Workaholics don't like to be called workaholics, but Bo definitely is one," says his wife, Millie. "I try to calm him down. It bothers me when, for instance, he throws his cap down on the sidelines.

"I'm constantly telling him to take care of himself, eat less, do his running. But he doesn't do that during the season, and I realize that he could have another heart attack. But Bo is Bo and I'm not going to change him.

"Certainly, he gets uptight, emotional, intense.But he also has a marvelous sense of humor and he's nice to be around . . . except when they lose."

That rich two-sidedness of Schembechler's is, however, seldom seen.

"Some people are actually surprised when they meet me to see that I'm human," Schembechler said this week.

"Since I learned the game under Woody Hayes, it's always been assumed that I was his clone.

"Actually," Schembechler says with the devilishness of a man who loves to joust with words, "i'm just a real nice guy . . . just a plain old ordinary nice guy who happens to like to coach football."

That is extremely close to the every day garden variety truth. Yet Schembechler's niceness, his prickly humor, is well hidden from public view.

Outside of Michigan, Schembechler is often visualized just as his Ohio State foes caricature the sour, bad-tempered Baron von Schembechler: the perfect villain.

One of his few concessions to relieving the pressure on himself is that Schembechler makes almost no attempt to hide his feelings or disguise his displeasure. He can be honest well beyond the point of bad manners.

The only people in his smallish universe who are almost forced to brook him are the press. Schembechler lets 'em have it right back, especially the people from school papers and small dailies.

"Sir, should you have keyed more on (Carolina's) Amos Lawrence?" asked a collegiate reporter.

"Don't tell me who to key on," growled Schembechler, in what has become an ugly ritual of bear-baiting after each of Michigan's flops in big games. "Son, you don't know enough about football to ask me about keys."

Schembechler almost deliberately shows the least appetizing sides of himself to the public. Yet even that is in character. He is a stubborn man. h

For years, he has been warned that if he didn't start recruiting punters and kickers he would pay the piper. Walk-ons and good luck couldn't hole out forever.

So, this season, all four Michigan losses were traceable to a kicking game that was a joke by major college standards. A conservative estimate of Michigan's booting sins in the Gator Bowl included a missed extra point and a loss of at least 150 yards in comparative field position on punts (six for each team) and kickoffs (four by each).

That stubborness shows its worst aspect when Schembechler occasionally dissociates himself from his player's failings.

"They're just not good enough to win these kinds of games yet," Schembechler said Friday night.

Schembechler can be excused for many things. The tightrope he walks is higher and thinner than the ones that torment other coaches.

Now, he must face the toughest of all his decisions.

Never before at Michigan has he lost four games in a season or three in a row. Never has his recruiting position been so weak due to that incredible 0-10-1 albatross that no longer can be attributed only to glamorous Rose Bowl losses.

Most coaches, in such a predicament, would hit the recruiting trail with doubled vigor. Work would be their solution.

Schembechler, out of necessity, must show restraint in the grinding recruiting travels.

Bo Schembechler is the strong man at the base of a huge human pyramid. He feels all the weight, and, because it is his nature, cannot help but take it to heart.