At 11.58 hours on 10 Jun, 1942, U-68 fired one torpedo at the unescorted Port Montreal (Master John Geoffrey Lewis) northeast of the Panama Canal from a distance of about 2000 metres. The wake was spotted on the ship and she turned to evade but because of that the torpedo hit the stern and caused the ship to sink fast. The commander noted in the KTB that the shot was out of desperation and the hit was very lucky.
At 19.30 hours on 8 June, the vessel had picked up 43 survivors from Tela, which had been sunk by U-504 (Poske) on 8 June. The master, 42 crew members, two gunners and the 43 survivors abandoned ship in four lifeboats but two men from Tela later died in the boats and were buried at sea. The survivors were picked up on 16 June by the Colombian schooner Hiloa and landed at Cristobal the next day.

The master, John Geoffrey Lewis had already survived another sinking when the Port Hardy was sunk in convoy HX-121 by U-96 (Lehmann-Willenbrock) on 28 Apr, 1941.