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
Saildrive Oil
Oil specifications: 80W90W gear oil (API GL-4 or GL-5)
Oil capacity: 700ml
Oil change interval: Every 250 hours of operation or annually (whichever comes first)
Part Numbers
Saildrive seal replacement kit
196313-02591 Saildrive seal, oil prop shaft (Qty 2 per saildrive)
24321-000950 Saildrive rear cover O-ring (Qty 2 per saildrive)
24341-000125 O-Ring, drain plug (Qty 1 per saildrive)
196315-02880 Circlip, Needle 52 (optional to reposition seals) previously 196313-02600
Others
196420-02551 Rubber protector, saildrive leg
196420-02602 Saildrive, rear cover
196311-04060 Needle Bearing (supports propeller shaft, replace if needles fall out or are loose)
196440-02701 Bolt, Bracket (Split zinc bracket, flat head M6X18)
26453-100252 Bolt, M10X25 (Saildrive rear cover bolt)
196420-02530 Drain, M10 (Saildrive oil plug)
Procedure to change oil in the water:
- Using a pump with a small tube remove as much oil as possible
- Refill oil to full capacity (bottom of dipstick)
- Run engine 5 minutes
- Using a pump with a small tube remove as much oil as possible
- Refill oil to full capacity (bottom of dipstick)
- (This will replace over 75% of the oil)
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.
Propeller Shaft Grooves
It is an issue that they Gori propellers installed on a SD20 saildrive will form grooves over time which will result in sea water penetration. Periodic repositioning of the seals using shims allow longer life from the propeller shafts.
Notes:
Blown seals: The SD20 is susceptible to blowing the seals if the oil is filled too high. Many have added a vent line to the top of the filler cap. Without the vent, only fill the saildrive oil to the bottom of the dipstick
Sheared tapper pin repair: External Link
