Both men were accused of attacking the same altar boy - Engelhardt in 1998, Shero in 2000 - when they worked at the St. Jerome Parish in the Northeast. Both had pleaded not guilty.
District Attorney Seth Williams later told reporters that Shero faces up to 57 years in state prison and Engelhardt faces 37 years when both are sentenced April 18 by Judge Ellen Ceisler.
"You saw in the course of this trial how they tried to victimize and demonize the victim of this case," Williams said. "So, I'm very thankful that the jury listened and rendered the verdicts that they did to hold these two men accountable, responsible for the heinous crimes that they committed."
Ceisler revoked bail for both defendants and ordered that they be held in protective custody because of the media attention the case has received.
The accuser, 24, whose name the Daily News is not publishing, testified during the trial but wasn't in court for the verdict.
He had returned to Florida, where he now lives, said attorney Paul Lauricella, who is representing the man in a civil lawsuit against the defendants and the Archdiocese of Philadelphia.
Engelhardt and Shero are the third and fourth men to be convicted after the D.A.'s investigation of clergy child abuse in the Archdiocese.
Last July, Monsignor William Lynn, 62, became the nation's first Catholic church official to be convicted of covering up the crimes of predator priests. He is serving three to six years in prison. Defrocked priest Edward Avery, 70, pleaded guilty last year to sexually assaulting the same altar boy as Shero and Engelhardt. He was sentenced to 2 1/2 to five years in prison.
The Rev. James Brennan, 49, whose trial for allegedly sexually assaulting a 14-year-old boy in 1996, ended in a mistrial last year. He will be retried in March.
Kenneth A. Gavin, a church spokesman, declined to comment on the verdict.
During the trial, defense attorneys for Shero and Engelhardt painted the accuser as a troubled drug addict who told multiple versions of his abuse story and was looking for a big payday from his pending lawsuit.
"[The accuser] is a lost soul. He is a sad individual. We hope that his life comes back together, but Father Engelhardt was not the cause," attorney Michael McGovern told reporters.
"He was very upset, very distraught," attorney Burton Rose said of Shero, after deputies removed him from the courtroom. "I felt the same way."
An appeal is coming, Rose added. McGovern said he would do whatever it takes to clear Engelhardt's name.
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