Saildrives

Manufacturer: Yanmar
Description: Saildrive Unit
Model: SD20
Manual: File:SD20 Operations Manual 2009.pdf
Parts catalog: File:SD20 Part Catalog.pdf
O-Ring parts diagram: File:SD20 O-rings Parts Diagram .pdf
Service Bulletin - Taper pin: File:SD20 Taper Pin Bulletin.pdf

Notes:
Oil change interval: Every 250 hours of operation or annually (whichever comes first) Oil: 80W90W gear oil (API GL-4 or GL-5) Outer diaphragm and secondary inner diaphragm
Replacement Guidelines: Inspect every 2 year and replace every 5 years
Common Practice: Monitor condition and test the water penetration sensor
Recommendations: Pacwest in San Diego does not recommend changing the diaphragms unless there is visible damage or water has penetrated the outer diaphragm. These diaphragm almost never fail. I have read this from other sources who make the same recommendation.