The Montgomery County Republican Central Committee agreed not to endorse a candidate in the county executive primary, despite a recommendation by its subcommittee to back Silver Spring Realtor John P. (Jack) Hewitt.

The central committee members, meeting late Tuesday, decided they would maintain the party's traditional position of neutrality in contested primaries.

Hewitt's supporters on the central committee, from the party's conservative faction, had been pushing for an early endorsement to lend credibility to Hewitt's fledgling campaign. Hewitt said he has raised only about $570 and he is running for the executive nomination in a party he joined just last month.

Hewitt is running in the GOP primary against Del. Luiz R. Simmons and banker Joseph McGrath.

Simmons, a moderate-to-liberal Republican, has touted himself as the candidate best able to attract Democratic voters in November, in a county with a 2-to-1 edge in Democratic voter registration. But Simmons' liberal philosophy has alienated the county GOP's small but vocal conservative wing, which has split between backing McGrath and Hewitt.

Some political observers were speculating that Hewitt needed the official endorsement of the central committee to convince potential donors that he could win in a Republican primary.

Hewitt said yesterday he would begin more active campaigning and fund-raising after the July 6 filing date for candidates. He said his campaign received "one hell of a boost" to be even considered for an endorsement by the traditionally neutral central commmittee.

"Don't you believe any rumors that I am going to get out," Hewitt said. "I started out running for county executive and I am going to run."