CDI YAMAHA PARSUN 65W-85540-00 PAF25-05090001

Function and technical context

The CDI (Capacitive Discharge Ignition) unit is the central component of the ignition system on Yamaha and Parsun two-stroke outboard engines. This device generates and distributes the high-voltage electrical pulses necessary to activate the spark plugs at the exact moment of the engine's compression cycle. It operates integrated into the ignition system without contact points, guaranteeing precise and consistent ignition in all navigation conditions. Its direct operation is essential for reliable starting, smooth acceleration and sustained engine power; Any deficiency in its operation causes misfires, loss of revolutions and serious difficulties during maneuvering in open water.

When to replace this part?

Typical faults of a faulty CDI unit include difficulty starting cold, intermittent loss of revs while cruising, and sudden shutdowns under acceleration or in tight corners. Although there is no fixed preventive maintenance interval for this component, it is recommended to inspect its condition at each annual seasonal inspection, especially if the engine has been exposed to prolonged humidity or has been subjected to shock. Preventive replacement of the CDI unit on engines more than ten years old or after diagnosed failures avoids costly emergency repairs at sea and ensures ignition system reliability throughout the boating season.

Equivalent manufacturer part numbers