→NOTE:
Components of the hydrostatic drive unit are not serviceable except for the seals.
[1] – Remove lever from control shaft. Clean shaft of any dirt or burrs.
[2] – Remove socket-head bolts (A and B). Separate valve block from housing.
[3] –
→NOTE:
Keep hydrostatic pump and motor rotating assemblies on shafts. Be careful to not scratch mating surfaces of rotating assemblies and plates.
Inspect motor (c) and pump plates (D) for wear.
[4] – Remove and inspect valve (E).
[5] – Remove and inspect reverse valve (F).
[6] – Remove and inspect forward valve (G).
[7] – Remove gasket (H). Ensure that all gasket material is removed from block passages and bearing surfaces.
[8] –
→NOTE:
Keep hydrostatic pump and motor rotating assemblies and components
separated for later reassembly to proper location.
Position housing on its side to remove pump and motor rotating assemblies.
[9] – Remove pump and motor rotating assemblies. Inspect plungers for wear or damage.
[10] – Inspect mating surface for scratches.
[11] – Inspect spring inside of rotating assemblies.
[12] – If disassembly is required, press in washer with appropriate sized socket and remove snap ring (I), washers (J), and spring (K).
[13] – Remove pump outer race (L) and thrust bearing (M).
[14] – Remove motor race (N), thrust bearing (O) and motor output shaft (P).
[15] – Inspect thrust bearings, races, and shaft surfaces for damage.
[16] – Remove snap ring (Q) securing through shaft assembly to housing.
[17] – Tap shaft with seal, spacer, and bearing from housing. Inspect bearing for damage.
[18] – Remove socket-head bolts from trunnion bearing housings (R). Hold swash plate (S), and remove housings with care to protect swash plate trunnion bearing surfaces.
[19] – Remove swash plate, exercising care to protect bearing surfaces.
[20] – Inspect trunnion bearings and bearing surfaces for wear or scratches.
[21] – If damage to any bearings or bearing surfaces are found, replace complete hydrostatic drive unit.
