3E5239 relay assembly 381-2491 fan CAT bulldozer parts

3E5239 relay assembly 381-2491 fan CAT bulldozer parts

The 3E5239 relay assembly and the 381-2491 fan are core control and execution components of the Caterpillar bulldozer cooling system. Strictly adhering to Caterpillar original equipment manufacturer (OEM) manufacturing standards and design tolerances, they are specifically designed for the heavy-duty, dusty, and high-vibration operating conditions of Caterpillar bulldozers. Working together, they achieve precise start/stop and temperature control of the engine cooling fan, effectively preventing engine overheating, equipment downtime, or damage to core components due to cooling failure. They are the preferred OEM-grade parts for the repair, maintenance, and replacement of Caterpillar bulldozer cooling systems, and are widely applicable to various harsh operating scenarios such as mining, infrastructure construction, and earthmoving projects.

The 3E5239 relay assembly, as the “control center” of the bulldozer cooling system, undertakes the core tasks of transmitting fan operation commands and controlling their on/off states. It accurately responds to engine temperature signals, achieving efficient regulation of the cooling circuit. The components utilize Caterpillar-specific high-purity copper coils, with a switching response speed of ≤8ms and a contact resistance of <0.01Ω, ensuring stable and lossless circuit transmission. The housing is made of high-strength, high-temperature resistant engineering plastic with a wear-resistant, oil-proof, and dust-proof surface treatment, achieving an IP65 protection rating. It can withstand extreme temperatures from -40℃ to 120℃, strong vibrations, and dust and oil corrosion, effectively resisting the risks of short circuits and burn-out. It adopts an original factory standard pin design, with anti-oxidation gold-plated terminals. The mounting holes perfectly match the original factory layout, allowing for direct plug-and-play adaptation without additional adjustments, significantly improving maintenance and replacement efficiency.

The 381-2491 fan, as the “cooling core” of the bulldozer’s cooling system, focuses on rapid engine heat dissipation. It adapts to the relay assembly control signal, efficiently circulating the cooling medium to ensure the engine maintains optimal operating temperature under heavy loads. The fan uses high-strength alloy blades with compliant dynamic balance, ensuring smooth, vibration-free operation and airflow output that meets Caterpillar’s original factory standards. The blade material is impact-resistant and age-resistant, able to withstand impacts from construction site debris and gravel, and will not deform during long-term operation. It adheres to original factory installation dimensions, with a stable and reliable mounting bracket, seamlessly integrating with the 3E5239 relay assembly to ensure a closed-loop control and execution system for the cooling system, providing robust heat dissipation for stable equipment operation.

Both components are Caterpillar’s original factory QAP quality certified, undergoing rigorous performance tests including high temperature resistance, vibration resistance, fatigue resistance, and corrosion resistance. Their quality is completely identical to original factory parts, allowing direct replacement without additional modifications or circuit matching, effectively reducing equipment downtime for maintenance. Whether for routine maintenance, system upkeep, or emergency fault replacement, the 3E5239 relay assembly and 381-2491 fan perfectly match the cooling system requirements of Caterpillar bulldozers, reducing long-term operation and maintenance costs and ensuring continuous and stable operation of the bulldozer in various heavy-duty tasks. They are suitable for all Caterpillar bulldozer models.

Core Technical Parameters

Compatible Models: Caterpillar bulldozers of all series

3E5239 Relay Assembly: Coil material is pure copper, response speed ≤8ms, contact resistance <0.01Ω, operating temperature -40℃~120℃, protection rating IP65, rated voltage DC24V

381-2491 Fan: Blades are made of high-strength alloy, airflow meets original factory standards, operating noise ≤75dB, mounting method is original factory specifications

Quality Standards: Meets Caterpillar original factory quality specifications, passes vibration resistance 12g@10~1500HZ cycle test and salt spray resistance 480-hour test

Core Advantages

Precise original factory fit, direct replacement without modification; sensitive temperature control response, efficient and stable heat dissipation; high temperature and vibration resistance, suitable for harsh working conditions; waterproof, dustproof, and corrosion resistant, long service life; closed-loop heat dissipation control reduces high temperature failures; quick and efficient installation reduces maintenance costs.

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0S-1604 Bolt
6V-3319 Seal – Oring
9W-4163 Race-RLR BRG
173-0888 Univ JT – Equivalent to Spider Gp
9H-3360 Seal-O-Ring (Final Drive Ar)
4H-6730 Seal – O – Ring
8E-8994 Seal – Ring
136-2967 Seal – O – Ring
468-3266 Valve Gp-MDL
3P-0653 Seal – O – Ring
361-7171 Seal-Lip Type
557-0249 Converter Gp – Torque
571-0489 Clutch Gp – Steering
2M-9780 SEAL-O-RING-STOR
6Y-3484 Bearing-Ball
3P-3441 Ring-Retaining
3T-3601 Ring-Spacer
8M-4389 Seal – O – Ring
3T-3602 Ring-Spacer
237-1016 Housing – Brake
106-0472 Hub – Input (No Output like D11)
9G-2991 Ring-Seal
6T-0234 Retainer
7T-6994 Plate – Clutch
6T-0842 Plate
219-7239 Spool
3T-4717 Spring
6T-0841 Plate
116-2592 Ring – Seal
6T-0840 Ring-Seal
255-9267 Disc As – Friction
364-2636 Disc – Friction
480-7885 Plate – Separator
106-0476 Retainer
282-4029 Final Drive
110-2780 Final Drive Arctic

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