Simplicity 1691682 Service & Repair Manual page 158

7 Transmission Repair
7B Sauer-Sundstrand BDU-21L-207
Figure B-2. Sauer-Sundstrand BDU-21L-207 Hydrostatic Drive Units Serviceable Parts
*1. Ring, Retaining
*2. Spacer
*3. Seal
*4. Seal
*5. Lip Seal
*6. Gasket, Center Section
*7. O-Ring, Rubber
8. Housing, Charge Pump
9. Geroter Assembly
10. Spring
11. Ball
12. Pin
13. Boss Plug, with O-Ring
14. Screw, M8x20
15. Screw, M8x35
16. Pipe Plug
*17. O-Ring, Rubber
18. Check Valve Kit
19. Spring
20. Check Valve Plug
21. Ball
22. Bypass Valve Kit
23. Bypass Valve Spool
24. Bypass Plug
*25. O-RIng
26. Spring
*27. O-Ring
28. Plug
29. Poppet, Orifice
30. Check Valve Kit
31. Overhaul Seal Kit (includes parts marked *)
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