CAT 336 340 345GC Fan Motor 598-7826 | Hydraulic Gear Motor for Caterpillar Parts

The 598-7826 and 505-5179 series hydraulic fan motors from Chengyuan Hydraulic are high-performance replacements engineered specifically for the next generation of Caterpillar (CAT) GC excavators, including the 336GC, 340, and 345GC. As a critical component of the C9.3B engine cooling system, this high-pressure gear motor delivers reliable high-speed output under extreme ambient temperatures. Every motor undergoes 100% simulated full-load and thermal shock testing before shipment to ensure its variable speed response matches the OEM standard, guaranteeing 100% original-place interchangeability.

Technical Specifications :

• Part Number (P/N): 598-7826 / 505-5179 / 605-5180

• Compatible Models: CAT 336, 336GC, 340, 340GC, 345GC

• Engine Match: Caterpillar C9.3B Tier 4 Final / Stage V

• Nominal Pressure: 210 bar (21 MPa)

• Peak Pressure: 250 bar (25 MPa)

• Displacement: Precision-matched to CAT cooling fan diameters

• Housing Material: High-strength, thermal-shock resistant cast iron

• Seal Type: Reinforced high-pressure shaft seals, rated for $-40°C$ to $+120°C$

Key Technical Advantages:

• C9.3B System Integration: The displacement and pressure curves are meticulously calibrated to align with CAT’s factory control strategies. It responds instantly to flow adjustments from the proportional valve during cold starts or maximum load operations, optimizing cooling efficiency.

• Reinforced High-Pressure Seal Technology: Since fan motors operate under continuous heat and backpressure, we utilize premium triple-lip high-pressure seals. Paired with a precision-ground shaft, it withstands high-frequency speed fluctuations without leakage.

• Low-Pulsation Gear Geometry: Optimized gear profiles reduce mechanical vibration caused by hydraulic ripples. This extends the service life of the fan blades and significantly lowers hydraulic noise levels during high-speed operation.

• Enhanced Heat Dissipation Housing: The housing design incorporates increased surface area for heat conduction. This ensures that internal components stay within the ideal lubrication temperature zone, even during 24-hour continuous heavy-duty cycles.

Application Areas:

• CAT 336/336GC Excavators: Primary hydraulic drive for the cooling system.

• CAT 340/345GC Excavators: High-capacity fan motor for large cooling modules.

• Dusty Mining Environments: Exceptional sealing integrity prevents dust ingress, protecting the overall hydraulic system from contamination.

Expert Maintenance Tips:

• Drain Line Integrity: Ensure the case drain line is clear and returns directly to the tank. Never plug the drain port, as excessive backpressure will blow out the shaft seal upon startup.

• Radiator Maintenance: Regularly clean the motor housing and the associated hydraulic radiator to prevent oil temperatures from exceeding $90°C$, which can lead to volumetric efficiency loss and premature seal aging.

• System Air Bleeding: After replacing the motor, run it at low speed with gradual speed increases to bleed air from the lines, preventing cavitation damage to the gear faces.