Hydrostatic Transmission Motor Disassembly and Assembly (4WD) (continued)
4. Inspect rotating components:
NOTE: Scoring is fine scratches or grooves cut into the highly
machined surface. When the scratches can be detected by feel
using a lead pencil or fingernail, the part must be replaced.
5. Check valve plate and cylinder block for grooves,
scor-ing, discoloration or pitting.
6. Check for free movement of pistons in cylinder bore.
7. Check pistons for flat areas, scoring or discoloration.
8. Thrust bearing (T) must rotate freely. (Fig. 56)
NOTE: Thin thrust plate (V), bushing (U) and motor
case (E) must be replaced as a set. (Fig. 56)
9. Inspect thin thrust plate (V) for wear or damage.
Re-place as necessary.
IMPORTANT: Avoid damage! Do not damage ball bearing
(D) when removing snap ring (B).
10. Remove snap ring (B) to remove shaft assembly
compo-nents.
11. Inspect bushing (U), thrust bearing (T) and shaft (G)
for wear or damage. Replace if necessary. (Fig. 56)
IMPORTANT: Avoid damage! Apply clean hydraulic
oil to all mating surfaces.
12. Assemble parts in reverse order of removal.
NOTE: Use petroleum jelly to hold valve plate in position.
• Put motor valve plate (J) on center valve block. Make
sure bronze surface is away from valve block and notch
in valve plate fits on locating pin of valve block.
IMPORTANT: Avoid damage! Pump and motor valve
plates are not interchangeable. The pump valve plate
has two lead-ing grooves into two of the slotted ports.
The motor valve plate (J) has no leading grooves.
NOTE: Motor case will seem springy because the springs
in-side the cylinder block are being compressed.
32
To Next Page
Loading...