Haymarket will lose two-thirds of its three-man, part-time police force Friday but speeding motorists will have little to celebrate in the small Prince William County town where enforcing the 35-mph speed limit is a major police occupation.

The town's long-time, part-time police chief, William V. Jones, who has worked without pay off and on for more than two decades, has been ill and will retire officially Friday. His long-time, part-time assistant, Burl Klein, is leaving the force to devote more time to his full-time job with International Business Machines Corp., according to Mayor Muriel Gilbertson.

Elected full-time police chief last week was Don Fasick, who has worked for the town part-time for about three years and has earned a reputation for strict law enforcement. He has antagonized some of Haymarket's 288 residents by giving them tickets along with those he has given to out-of-town commuters who speed through town on Rte. 55.

The good news for speeders, however, is that Fasick will only work five days a week. His schedule is not being made public, however, "because I don't think we ought to let people know when he will be working," Gilbertson said.