Caption: A CP mechanic is working on the MLW/ALCo 254 V-16 diesel engine of CP 4717, an MLW M636.
The externals of 6 of the 8 left side cylinders can be seen, with covers off 5 of them. The other 2 cylinders are hidden behind the middle access doors.

CP 4717 is surrounded by GMD locomotives; to the left is SD40-2 CP 5697, to the right is GP35 CP 5002.
The sound of a big ALCo engine starting up using its compressed air starter was memorable, and typically accompanied by a fair amount of black smoke.