Earl C. Mechtensimer, the deputy director Baltimore's City Hospitals, was at work last Friday when, he says, Prince George's County Executive Lawrence J. Hogan called to offer him the job of county hospital director.

"It was the first time I had heard from him," said Mechtensimer, who met Hogan in the late 1960s. "I had reservations about getting into the political arena, but I told him I would do it."

And so, last Monday morning, Mechtensimer arrived in Upper Marlboro for a press conference called to announce his appointment. But something was wrong. "Hogan walked right by me without saying a word," Mechtensimer said. "That's when he announced that he was withdrawing my appointment." At the time Hogan cited "logistical" problems for the "temporary" withdrawal of the nomination.

Yesterday, Mechtensimer had still not heard from Hogan but, through reporters phone calls, he had been informed that Hogan had eliminated him from consideration.

That made Mechtensimer angry. "This is because he was told allegations that I flunked out of two PhD programs," Mechtensimer said, "which is absolutely untrue."

Mechtensimer said that he had resigned his job at Baltimore City Hospitals, when he got the job offer, and because of Hogan's reversal was going "to have to do some real searching. I just hope he's happy with what he's done," Mechtensmer said.

Apparently Hogan's abrupt reversal Monday was prompted by phone calls from councilmen Francis B. Francois and Parris N. Glendening. In little more than an hour of checking that morning the councilmen had turned up enough allegations about Mechtensimer's record to persuade Hogan he had made a mistake.

"I don't want to malign the guy," Hogan said, "but we received some reports-some from council members, some from state officials and others who called in after the story broke-who indicated things that made him unsuitable."

According to council members, the allegations included charges that Mechtensimer had failed to complete a PhD. candidacy at St. Louis University, had flunked out of another PhD. program and that Baltimore City Hospitals officials were attempting to reorganize him out of his job.

Asked if Hogan's staff had checked out the allegations, aide Robert T. Ennis said, "they may or may not be accurate."

Mechtensimer heatedly denied the charges yesterday. He said he had studied at the State University of Iowa for a Ph.D. in health care administration, then had transferred "in good standing" to St. Louis University.

He added that he had completed his Ph.D. candidacy in 1964, but recently discovered that his degree had been denied because he had not completed his dissertation within five years of completing his course work. Mechtensimer said he has still not written his dissertation. He understood the time limit to be 15 years, he said, and has written to the university president to try and correct the situation.

But, Mechtensimer said, he was not surprised by his sudden change in fortune. "I don't know why Hogan hasn't called me," he said. "But nothing surprises me when you're in a political arena."

Hogan, who originally met Mechtensimer during the 1960s when he was visiting The Hospital for Sick Children in D.C. where Mechtensimer was executive director, said yesterday that "somebody should have called" Mechtensimer to inform him of the change in appointment.

But Hogan added, "He may not get his (Baltimore) job back, but that's not because of this. There are other reasons."