Hydraulic Pump 708-3S-00521 Fan Motor Komatsu

Product Overview

708-3S-00521 hydraulic fan motor is OEM-grade heavy-duty cooling replacement part precisely manufactured for Komatsu PC40MR-2 and PC50MR-2 compact mini excavators.

Serving as the core power assembly of radiator cooling loops for these two popular compact excavator variants, this electro-proportional hydraulic fan motor intelligently adjusts fan rotational speed responding to real-time shifts in engine coolant and internal hydraulic oil temperatures. It delivers consistent heat dissipation across diversified small-scale construction scenarios, including narrow municipal trench works, residential landscape renovation, light foundation excavation, confined building refurbishment and scattered farmland earthworks. Adaptive speed regulation effectively prevents engine thermal overload under frequent cyclic start-stop operations, and optimizes fuel efficiency by cutting redundant fan rotation during intermittent idle periods that frequently emerge at small construction job sites.

Product Highlights

✅ Dual-Model Tuned Proportional Speed System

Dedicated compact DC12V proportional solenoid achieves smooth stepless speed adjustment tailored to the operational traits of PC40MR-2 and PC50MR-2. Fan speed automatically rises throughout sustained digging assignments to deliver adequate cooling output, and lowers during frequent work pauses to reduce idle engine power wastage and cut long-period fuel expenditure.

✅ Perfect OEM Mounting Fit for Restricted Engine Bays

Downsized reinforced mounting flanges, finely machined hydraulic port threads and matched shaft splines precisely adapt to the narrow installation space of the two excavator variants. No on-site metal cutting or hydraulic pipe rework is required during replacement, greatly shortening equipment downtime in crowded urban streets and residential construction plots.

✅ Space-Saving Anti-Vibration Cast Iron Shell

Thickened compact cast iron casing dampens continuous micro-shocks brought by frequent short-stroke digging, avoiding housing deformation and loosening of delicate internal hydraulic components under intensive daily working cycles.

✅ Multi-Scenario Dust & Mud Resistant Sealing Design

Layered premium fluorine rubber sealing rings paired with mini outer dust gaskets keep concrete powder, gardening soil and damp trench sludge away from internal mechanical structures, slowing seal abrasion in landscaping projects, municipal trench assignments and muddy suburban construction locations.

✅ Multi-Stage Pre-Shipping Quality Screening

All finished units pass 22MPa 30-minute pressure retention leak inspection, precision linear speed calibration and a 2.5-hour continuous full-load aging test. Hidden manufacturing defects get eliminated in advance to reduce recurring follow-up maintenance tasks on construction sites.

✅ Two Practical Budget-Oriented Procurement Solutions

Brand-new factory-standard products meet strict official dealership maintenance criteria; remanufactured units fully renew worn internal hydraulic core components, bringing notable cost advantages for wholesalers maintaining bulk mini excavator spare inventories.

✅ Improve Overall Stock Management Efficiency

One spare product can adapt to two mainstream Komatsu mini excavator models, lowering required SKU quantity, simplifying warehouse sorting work and cutting capital locked inside scattered spare stock.

✅ Dynamically Balanced Mini Internal Rotor Assembly

Scaled-down rotating internal parts go through professional dynamic balancing processing to suppress vibration and operational noise, delivering solid protection for fragile compact radiator fins placed within cramped engine compartments.

✅ Extend Lifespan of Compact Hydraulic Circuits

Stable temperature control keeps small-displacement engines and matched hydraulic fittings within optimal working temperature bands, slowing ageing of miniature pump internals, slim rubber hoses and peripheral seals amid frequent startup and shutdown operation rhythms.

✅ Excellent Global Logistics Adaptability

Compact overall dimensions help decrease international shipping expenses, shockproof industrial packaging performs reliably during sea freight, air transportation and ordinary parcel delivery. Tiered bulk purchase discounts are available, backed by unified 6-month global warranty excluding human-induced damage and incorrect mounting.

Condition: Brand new

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