C-FIGX, a privately operated float-equipped Noorduyn Norseman MK. VI aircraft, was conducting a flight from Stein Lake, SK to Emma Lake, SK. While cruising at 3 500 feet ASL, the engine (Pratt & Whitney – USA, R-1340-AN-1) developed a vibration, and the oil pressure indication decreased from 90 psi to 60 psi. The pilot elected to divert and commenced a descent toward Montreal Lake, SK. The pilot selected the mixture to rich and carburetor heat on. The fuel selector was moved from the belly tank to the wing tanks and the magneto switch was checked. The pilot asked the passengers to secure the cabin, and the subsequent precautionary landing on Montreal Lake was uneventful.
The pilot initiated a rescue using a cell phone and 121.5 radio transmissions. The occupants were transported to shore with a boat provided by RCMP. The aircraft was then towed to shore at Weyakwin Landing.
Inspection of the engine revealed that the No. 4 cylinder had failed.
The engine will be removed for inspection and repair.