Install new seals and O-rings at all locations when assembling the hydrostatic drive unit.
Ensure that all components are free of dirt or other contamination. Protect bearing and sealing surfaces during reassembly.
[1] – Protect bearing surfaces (A) of swash plate trunnions.
[2] – Install swash plate (B) to transaxle housing.
[3] – Lubricate and install new O-rings (C) to left and right trunnion bearing housings.
[4] – Lubricate and install new control shaft seal (D) to bearing housing.
[5] – Lubricate trunnion bearing surfaces and install bearing housings to transaxle housing.
[6] – Apply thread lock and sealer (medium strength) to threads of socket-head bolts (E).
Install and tighten to specification.
[7] – Install input shaft (F) with bearing to housing. Press against outer race of bearing to fully install bearing to housing bore.
[8] – Install spacer (G).
[9] – Lubricate input shaft and new seal (H). Install seal flush with housing surface.
[10] – Install snap ring (I).
[11] – Install output shaft (J).
[12] – Install ball thrust bearing (K) and grooved outer race (L).
[13] – Install roller thrust bearing (M) and flat outer race (N).
[14] –
→NOTE:
Positioning the hydrostatic motor housing on its side at a slight angle keeps thrust bearing components and pump and motor components in place as they are installed.
Carefully install pump (O) and motor (P) rotating assemblies to housing shafts, ensuring that pistons remain in cylinder blocks.
[15] – Ensure that pump and motor wear plates are correctly installed to valve block locating pins (R). Pump wear plate tapered grooves (Q) must face pump rotating assembly.
[16] – Install new gasket (S) to valve block. Ensure to align holes in gasket with locating pins in block.
[17] – Lubricate check valve seal rings. Install check valves.
[18] – Lubricate and install new O-rings to relief valve. Install valve to block.
[19] – Apply thread lock and sealer (medium strength) to threads of socket-head bolts (T and U). Install and tighten to specification.
