Yanmar SD40 | SD50 Sail Drive Unit Service Workshop Manual

Workshop Service and Repair Manual for the Yanmar SD40, SD40-4T & SD50, SD50-4T Sail Drive Units, an absolute gem for anyone working on these units. This full workshop manual covers every component, service and repair procedure in full Yanmar factory specification with clear step by step technical drawings for the Yanmar SD40, SD40-4T & SD50, SD50-4T Sail Drive Units with torque setting values throughout each chapter, this is the most comprehensive service manual available as used by boatyards and independent marine engineers the world over.

Below is a list of the items covered within this manual.

1 General
Specifications
Exterior view
Sectional view
Criteria for replacing parts
Route of cooling water and lubricating oil
Lubricating oil
Disassembly and reassembly
Special tools
Notes on disassembly, inspection and reassembly

2 Disassembly
Disassembling the upper case
Removal of the unit
Disassembling the unit
Disassembling the lower case
Removal of unit

3 Reassembly
Reassembling the bearing for lower case
Needle bearing
Taper roller bearing outer race
Reassembling the bearings of shaft
Propeller shaft
Driveshaft

4 Shim adjustment (Gear backlash adjustment)
Location of adjustment shims
Measurement of the dimensions of the cases
Upper case
Lower case
Shim selection method for the clutch shaft
Measurement of the dimensions (L1, L2, L3) of the gear
Calculation of the shim thickness
Shim selection method for the pinion shaft
Measurement of the pinion dimensions
Calculation of the shim thickness
Shim selection method for the driveshaft
Measurement of the dimensions (M1) of the pinion
Calculation of the shim thickness
Shim selection method for the propeller shaft
Measurement of the dimensions M3 of the gear
Calculation of the shim thickness

5 Adjustment of bearing assembly gap
Upper gear bearing
Measurement of the bearing dimension
Calculation of the shim thickness
Pinion shaft bearing
Measurement of the bearing dimension
Calculation of the shim thickness
Pinion drive shaft bearing
Measurement of the bearing dimension
Calculation of the shim thickness
Propeller shaft bearing
Measurement of the bearing dimension
Calculation of the shim thickness

6 Adjustment of the gear backlash
Upper gear
Lower gear

7 Adjustment of the gear dye pattern
Upper gear
Propeller shaft

8 Adjustment of the shift lever
Measurement of the dimensions
Shift Lever bolt
Shifter pin position
Calculation of the shim thickness
Caution of reassembly

9 Tightening torque for nuts and bolts