Jack Pardee was 13 when he first worked in the West Texas oil fields. Thirty-two years later he is returning, starting a new life back home after deciding to get off what he calls the football roller coaster.

It wasn't an easy decision. Pardee has devoted 26 years to football, ever since he played for Bear Bryant at Texas A & M. Even under someone as demanding as Bryant, football was fun. Even in the World Football League, when neither coach-general manager Pardee nor his Florida Blazers were getting paid, football was fun.

Now, he says, football isn't that much fun.

"I felt before that I couldn't be without football," Pardee said. "Now I feel I can be very comfortable without it."

That's why Jack Pardee, twice NFL coach of the year, left his job as assistant head coach of the San Diego Chargers last week to sell oil field mud.

"After what has happened the last two years," he said, "I was just ready to try a different line of work. If I wanted to be an assistant coach the rest of my life, I'd still be in football. I could be in football until I wanted to retire. But I didn't want to be an assistant. I didn't think that was right for me."

After the 1979 season, Pardee thought he had the best job in football. He was coaching the Washington Redskins, molding what he thought would become a perennial contender after just missing the playoffs that year. He had a beautiful farm in Loudoun County, his family loved the area and he was well-respected.

After the 1980 season, he was unemployed, fired after one losing season. He says he understands the decision, but it still hurts. He felt the situation was handled poorly and unjustly by owner Jack Kent Cooke. That's when football started to be less fun and more work.

Now he is trying to put football behind him.

He admittedly gambled when he decided to become a Charger assistant last year. He figured if he stayed active and improved the San Diego defense enough to get the Chargers into the Super Bowl, owners would come calling, offering him another head coaching spot.

Instead, the Charger defense was one of the league's worst. He was criticized by fans and the media. San Diego didn't make the Super Bowl and the owners didn't come calling.

"Maybe some nibbles," he said, "but nibbles don't count. I didn't get a bona fide offer to be a head coach after the season had ended.

"What did that tell me? It told me . . . I had to decide whether I wanted to continue as an assistant coach or do something else. I suppose I could have waited for another couple of years to see what happened, but then I'd be near 50. This way, I'm giving myself 20 years to get involved in another endeavor. I'm giving myself a chance."

There was a long silence.

"This hasn't been an easy move. But you have to look at the entire picture. I love to coach. But there's more to it than that. Is everything else you have to put up with worth it? That part of the business isn't going to change."

Pardee always has been uncomfortable with certain aspects of coaching. An introvert, he didn't relish the attention given a coach of his stature. A friendly, straightforward person, he didn't understand the in-fighting and office politics.

He is aware there has been speculation that he left San Diego with a prod from the Chargers. The team denies it and he denies it, and sources in San Diego confirm the decision was Pardee's.

"Let people think what they want," Pardee said. "They are going to anyway. This was my choice, made on my own. After all these years, do you think I'd run from criticism?"

But is he running to the oil fields only to wait for a head coaching job?

"I can't say I'll never coach again," he said, "but I'm certainly going into this with the idea that this will be my job from now on . . . I'm sure I'll miss football, but I hope I'll miss it only on Sundays, not during the week. Anyway, if I didn't get an offer this year, why would I get one another year?"

Pardee will begin his new job--he probably will be the marketing director for his new employer, the Runnels Mud Co., which sells specially developed mud that is used as a lubricant for drill bits--in early March. He will live in Midland, Tex., 90 miles from where he grew up in Christoval.

As he sees it, this was a good time for a change. Four of his five children are in college this year, and two will graduate this spring. One is getting married.

"I got my first job in the fields when I was 13," he said. "I worked in them during the summers until I got out of college. It was hard work and I can't say I liked it. That's why I'm glad I'm going back but at a different end of the business. I'll be selling rather than working in them.

"Living again in Texas will be good. It's a great place if you know what to expect and I think we know what to expect. I had a chance to take this job two years ago, but I wanted to wait."

He still owns his farm in Middleburg, but says he'll probably sell it.

"Chances are pretty remote," he said, "that we'll ever be back there to use it."