Power unit replacement system for a work machine

A machine, comprising:

• a frame;
• a lift system, comprising:
• a lift arm attached to the frame,
• the lift arm configured to actuate between a raised position and a lowered position;
• and
• a roller, attached to the frame, configured to slidably engage with a cam element of a power unit for the machine during actuation of the lift arm, wherein the roller has inwardly tapering ends configured to align the cam element to a center of the roller;
• and
• a lock system, comprising:
• a latch element;
• and
• a locking cylinder configured to extend to a locked position in the latch element and retract to an unlocked position from the latch element,
• the locking cylinder configured to engage a locking lug of the power unit.

A power unit for a machine, comprising:

• an energy storage unit;
• and
• a power unit housing, containing the energy storage unit, comprising:
• an engagement element configured to engage the power unit housing with a lift arm of the machine;
• and
• a cam element projecting outwardly from the power unit housing and having a continuously convex exterior surface configured to slidably engage with a roller of the machine during actuation of the lift arm.