Part of the Yanmar Repair Manuals.
Split the upper case on an SD40 or SD50 and the first thing you learn is that nothing goes back together by feel: gear position lives in shim stacks, and the cone clutch only holds if the bearing gaps are right. This 69 page Yanmar service manual, publication M2215-04E140, is the factory procedure for getting every one of those numbers.
It covers the SD40-3, SD50-3, SD40-4, SD50-4, SD40-4T and SD50-4T sail drive units used with the 3JH3CE, 3JH4CE, 4JH3CE, 4JH4CE and 4JH3-TCE engines. Inside are full disassembly and reassembly sequences for the upper and lower cases, shim selection with the measurements and calculations written out, gear backlash and dye pattern checks, shift lever adjustment, and the tightening torque table for the shaft nuts and bolts.
It is a bookmarked PDF, so the replacement criteria and torque figures travel with you, whether the unit is on the bench in pieces or bolted back into the boat.
Complete the set for your SD40–SD50 Series
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| History of Correction | 2 | Manual Name |
| For Safety | 5-10 | Safety Labels, Service Area, Work - Wear (Garments), Tools, Fastener Torque, Further Precautions |
| General | 11-29 | Specifications, Exterior View, Sectional View, Criteria for Replacing Parts, Route of Cooling Water and Lubricating Oil, Lubricating Oil, Disassembly and Reassembly, Special Tools |
| Disassembly | 30-47 | Disassembling the Upper Case (Removal of the Unit, Disassembling the Unit), Disassembling the Lower Case (Removal of Unit) |
| Reassembly | 48-49 | Reassembling the Bearing for Lower Case (Needle Bearing, Taper Roller Bearing Outer Race), Reassembling the Bearings of Shaft (Propeller Shaft, Drive Shaft) |
| Shim Adjustment (Gear Backlash Adjustment) | 50-56 | Location of Adjustment Shims, Measurement of the Dimensions of the Cases (Upper Case, Lower Case) |
| Adjustment of Bearing Assembly Gap | 57-60 | Upper Gear Bearing (Measurement of the Dimension of the Bearing, Calculation of the Shim Thickness) |
| Adjustment of the Gear Backlash | 61-62 | Upper Gear, Lower Gear |
| Adjustment of the Gear Dye Pattern | 63-64 | Upper Gear, Propeller Shaft |
| Adjustment of the Shift Lever | 65-66 | Measurement of the Dimensions (Shift Lever Bolt, Shifter Pin Position), Calculation of the Shim Thickness, Caution of Reassembly |
| Tightening Torque for Nuts and Bolts | 67 | |
| Colophon | 68 | First Edition, Published by, Copyright |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Tightening torque for propeller shaft nut | 166.6±5.0 N-m (17±0.5 kgf-m) | p. 67 |
| Tightening torque for drive pinion end nut (left screw) | 147±5.0 N·m (15±0.5 kgf・m) | p. 67 |
| Tightening torque for pinion shaft assembly bolt | 73.5±3.0 N·m (7.5±0.3 kgf-m) | p. 67 |
| Needle bearing (A) (K24 x 28 x 17) replacement interval | Every 1500 hours | p. 14 |
| Needle bearing (B) replacement interval | Every 1500 hours | p. 14 |
| O-ring replacement criteria | Disassembly | p. 14 |
| Diaphragms (A) & (B) replacement criteria | Hair cracks | p. 14 |
| Lubricating oil type (API service grade) | GL4 or higher | p. 11 |
| Lubricating oil type (SAE grade) | SAE 80W-90 | p. 11 |
| Shift lever adjustment clearance | 0.2~0.4 mm | p. 65 |
| Reduction ratio (Ahead/Astern) | 2.32 | p. 11 |
| Allowable speed at Input shaft | 4000 min-1 | p. 11 |
