Montgomery County Executive Charles W. Gilchrist yesterday fired controversial liquor consultant Leonard I. Colodny less than two days after rejecting Colodny's offer to resign.

In a letter to Colodny, Gilchrist wrote that he was terminating Colodny's four-month contract because "based on your expressed desire to be released from the contract, I have determined that it is not in the best interest of the county to continue . . ."

Colodny had asked Gilchrist to release him from his contract because the county executive's top aides allegedly had asked him to revise sales figures to Schenley Industries Inc., a New York-based liquor company with ties to the Gilchrist administration, would not appear to receive as much business as it does from the county.

Gilchrist has denied that his aides attempted to influence Colodny.

On Wednesday night, Gilchrist sent a letter to Colodny saying it would be "appropriate" for him to continue his investigation of the county's Department of Liquor Control.

Gilchrist explained his change of heart by saying that Colodny never went to him directly to ask to be released from his contract. The executive said he read about it in the newspaper yesterday.

"Colodny just said that he didn't know if he could continue, based on what was going on," Gilchrist said through his spokesman, Charles Maier.

Colodny, a former Prince George's County liquor wholesaler, was hired as a consultant in May after reporters began making inquiries about the close connection between present and former employes of the Department of Liquor Control and liquor distillers, particularly Schenley.

The department administers the only county monopoly on wholesale and retail sales of liquor, wine and beer in the nation.

On Monday, Colodny said he received a phone call from Lou Roberts, who is Montgomery County's acting chief administrative officer while Robert Wilson is on vacation. The two discussed the contract, and Colodny says he asked Roberts:

"Will you please check with Mr. Gilchrist about the possibility of mutual termination of the contract?"

Colodny says that Gilchrist phoned several hours later, and that the two spoke about Colodny's plan to release his findings to the press. At the end of the conversation, Colodny says he told Gilchrist that because of the alleged interference in the study by the executive's top aides, Gilchrist should "seriously consider a mutual termination of my contract." Colodny says Gilchrist responded, "Uh-huh."

In his letter on Wednesday, Gilchrist wrote that he wanted Colodny to continue his study because he had not provided all the required data.

Yesterday, after Gilchrist fired Colodny, Maier said Gilchrist probably will hire "some big sophisticated consulting firm" to investigate problems in the Department of Liquor Control. Maier denied that Gilchrist fired Colodny because Colodny had found questionable practices by the Schenley Liquor Co. and the department.