Overview
The ZF 4143.020.183 2 HL 290 Hydrostatic Drive Assembly is a complete, pre-assembled unit designed for variable-speed propulsion in heavy-duty industrial machinery. This SKU 4143.020.183 integrates the hydraulic pump and motor within a single housing, converting engine power into smooth, stepless torque for ZF marine and off-highway transmissions. It sits at the heart of the driveline, directly coupling to the input shaft to manage forward and reverse motion without mechanical clutch engagement. The assembly is precision-machined to OEM tolerances, ensuring reliable oil flow and pressure regulation across the HL 100 and HL 270 series platforms.
Symptoms of Failure
- Erratic or surging drive speed: When the hydrostatic unit wears, internal pistons or swash plates lose seal integrity, causing inconsistent output RPM under constant throttle.
- External oil seepage at mating flanges: Deteriorated gaskets or housing cracks allow hydraulic fluid to escape, often visible as drips near the pump-motor interface.
- Loss of holding power on inclines: A failing assembly cannot maintain static pressure, leading to unintended vehicle rollback when stopped on a grade.
- Whining or grinding noise during engagement: Metal-to-metal contact from worn bearings or scored cylinder blocks produces audible distress, especially under load.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4143.020.183 |
| Assembly Type | 2 HL 290 Hydrostatic Drive (Complete Unit) |
| Housing Material | High-tensile cast aluminum alloy |
| Dry Weight | 38.5 kg (84.9 lbs) |
| Overall Length | 410 mm |
| Maximum Operating Pressure | 420 bar (6,090 psi) |
| OEM Reference | ZF 4143.020.183 / 2 HL 290 |
| Seal Kit Compatibility | 0634303266 O-Ring, 0501214034 Sealing Cap |
Compatibility
This hydrostatic drive assembly is engineered for ZF transmission models that require independent pump-motor integration. It is a direct fit for the WG180, WG200, and WG250 series, as well as the HL 270 and HL 100 series gearboxes. The unit also serves as a replacement in certain ZF 2 HL 290 splitter configurations. For proper installation, ensure the mating 4143101043 HOUSING and 4143301055 HOUSING are free of cracks, and that the 4143298040 CASE is aligned to the drive flange. Secure the assembly using the 0631329135 SPRING PIN to lock the control lever linkage.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4143101043 | HOUSING | Encloses the drive assembly, provides mounting points |
| 4143301055 | HOUSING | Secondary cover for pump-motor interface |
| 4143298040 | CASE | Main structural casing for gear train |
| 0631329135 | SPRING PIN | Retains control lever pivot |
| 0501214034 | SEALING CAP | Prevents debris ingress into hydraulic ports |
| 0636101024 | CAP SCREW | Fastens housing halves together |
| 4475280099 | SCREW PLUG | Seals test ports and drain holes |
| 0634303266 | O-RING | Hydraulic seal between mating surfaces |
| 4143301045 | SCREEN SHEET | Filters return oil before entering reservoir |
| 0636420051 | COUNTERSUNK SCREW | Secures screen sheet inside housing |
