The Red Devils missed a host of regulars, most of whom are away on international duty with Egypt, and they initially struggled against their lowly opponents.
Ahly also missed coach Pitso Mosimane, who returned to Cairo on Saturday after completing the CAF Pro Licence course in Morocco.
Mosimane's assistant Sami Komsan led the team, who struggled for openings in a drab opening.
It was Egy Salloum who had the first threat when a long-range shot from Abdel-Rahman Hammad was tipped over by Ahly's third-choice keeper Mostafa Shobeir.
Ahly improved in the second half and striker Hossam Hassan, who has hardly produced convincing displays since his arrival last summer, wasted a good chance in the early stages.
Abdel-Kader finally ended Egy Salloum's resistance on 59 minutes when a right-wing cross was cleared into his path and he calmly drilled a low shot into the far bottom corner.
Hassan spurned a glorious chance to make it 2-0 on 73 minutes, firing high over with the goal at his mercy after a low cross from the left found him unmarked.
The win comes almost two weeks after Ahly suffered a bitter 2-0 loss to Morocco's Wydad in the African Champions League final, which denied them an unprecedented hat-trick of straight crowns.