WISCASSET — A Superior Court jury found a gas station attendant guilty of rape Thursday after a three-day trial in which the defense rested its case without calling any witnesses.

Robert Harris, 37, was ordered held without bail while awaiting sentence. Justice Kermit Lipez set no sentencing date for Harris, who faces up to 20 years in prison.

Harris, who was extradited to Maine from a federal prison in Pennsylvania, faces additional prison time from earlier rape convictions in Canada and Ohio. He also is charged with a 1982 Woolwich rape that goes to trial next week in Rockland.

This week’s trial focused on charges that Harris raped an Auburn woman in June 1983 after she had stopped for gas at a Topsham service station where he worked.

The woman testified that Harris had insisted on checking the oil in her car the night she was attacked. The car subsequently failed to start, she said, and Harris grabbed her at knifepoint after he pushed the vehicle into a service station bay.

Defense Attorney Dennis Hagemann contended in his closing arguments that the state’s evidence was inconsistent and implied that the woman Harris was accused of raping may have wanted to have sex.

Jurors deliberated about four hours before returning their verdict.