Hitachi Center Gear 3104554 – Specification for ZX330-3 / ZX330-5A Hydraulic Pump (41×19T)

Description

Product Video

Detail Information

1. Key Features & Benefits

• Genuine Hitachi OEM specification – Part number 3104554. This center gear is manufactured to Hitachi’s original equipment standards for the ZX330-3, ZX330-5A, and compatible Zaxis series excavators. It is a critical internal component of the hydraulic pump gear train – not a generic aftermarket substitute. This is a brand‑new, factory‑spec unit.

• Center gear – the torque transmission core – The center gear (also known as the drive gear or sun gear) is the central component of the hydraulic pump’s planetary gear train. It transmits torque from the drive shaft to the planet gears of the planetary reducer, providing power distribution and output speed reduction. In the Hitachi HPV145 pump used on ZX330-3 and ZX350-3 models, this center gear is a key wear component that transfers engine power to the hydraulic pumping elements.

• Precision‑engineered 41×19T gearing – The gear features a 41‑tooth configuration with 19 teeth on the mating surface (41×19T). Manufactured from high‑strength alloy steel with precision‑ground tooth profiles to ensure smooth meshing, minimal backlash, and efficient power transmission under high hydraulic loads.

• Restores hydraulic pump performance – A worn or damaged center gear causes irregular pump operation, reduced hydraulic flow, loss of digging power, and increased noise from the pump area. Replacing a worn gear restores proper power transmission, consistent hydraulic output, and smooth machine operation. This part is essential for maintaining the original performance of the HPV145 hydraulic pump.

• Engineered for extreme durability – Built from case‑hardened steel with heat‑treated tooth surfaces to withstand the extreme torque loads and continuous operation typical of 30–40 ton class excavators in mining, quarrying, and heavy construction applications.

• Wide compatibility across Hitachi Zaxis series – Fits Hitachi ZX330-3, ZX330-3-HCMC, ZX330-5A, ZX350-3-AMS, ZX350H-3, ZX350K-3, ZX350LC-3-HCME, ZX400W-3, as well as ZAXIS300LC-6N, ZAXIS350LC-3, ZAXIS350LC-5A, ZAXIS350LC-6N, ZAXIS370F-3, ZAXIS380LC-5N, and ZAXIS380LC-6N. Also compatible with John Deere excavator models including 330CLC, 350DLC, 370C, and 892E.

• Pre‑shipment visual verification – Before packing, we send you detailed high‑resolution photographs of the actual gear (tooth condition, part number markings, overall condition). You approve shipment – we never ship blind. Video inspection is also available upon request.

• Fast delivery – 5–7 working days lead time from our Guangzhou warehouse. Flexible shipping options including DHL, TNT, UPS, FedEx, and sea freight.

2. Applications

The Hitachi center gear 3104554 is a critical internal component of the hydraulic pump gear train on 30–40 ton class excavators used across a wide range of demanding job sites:

• Large‑scale construction & earthmoving – Highway excavation, dam building, and large‑scale earthmoving projects place sustained high torque loads on the hydraulic pump gear train. The center gear transmits engine power through the planetary reduction to the hydraulic pumping elements. A worn gear results in reduced hydraulic flow, slower cycle times, and increased fuel consumption. Replacing a worn center gear restores full power transmission and hydraulic performance.

• Mining & quarry operations – In open‑pit mines and aggregate quarries, machines work 20+ hour shifts under extreme loads. The hydraulic pump gear train is subjected to continuous high torque and shock loads. A failed center gear can cause sudden pump failure, resulting in lost production and expensive recovery efforts. Genuine OEM gears provide the durability and reliability needed for these demanding conditions.

• Demolition & scrap processing – Shock loads, vibration, and rapid load changes are routine in demolition yards and metal recycling facilities. The center gear must withstand these extreme conditions without tooth pitting or fatigue failure. Genuine OEM heat‑treated gears provide the strength and durability required.

• Equipment rental fleet maintenance – Rental machines see heavy use from multiple operators, increasing the risk of component wear. A worn center gear on a rental machine can cause poor hydraulic performance and customer complaints. Proactive replacement with genuine OEM gears ensures predictable performance and minimises downtime.

• Forestry & land clearing – Steep slopes, fallen timber, and uneven terrain place variable loads on the hydraulic system. The center gear must transmit power reliably under changing load conditions. Genuine OEM gears maintain consistent power delivery for saws, grapples, and mulchers.

• Wheel excavator applications (ZX400W-3) – For wheeled excavators that travel on public roads between job sites, reliable hydraulic power transmission is essential for both road travel and worksite digging conditions. The center gear ensures consistent hydraulic pump output across all operating modes.

3. Maintenance Tips – Extend the Life of Your Hydraulic Pump Gears

A properly maintained hydraulic pump gear train is essential for the performance and longevity of your Hitachi excavator’s hydraulic system. Follow these tips to protect your investment:

• Change hydraulic oil and filters on schedule – Contaminated oil is the #1 killer of hydraulic pump internal components. The center gear operates in a high‑pressure environment where even microscopic abrasive particles can cause tooth wear and pitting. Use genuine or high‑quality filters and change them at Hitachi‑recommended intervals.

• Monitor hydraulic oil temperature – Excessive oil temperature (above 85°C) reduces the lubricating film strength between gear teeth, accelerating wear. If your machine runs consistently hot, check the cooling system and oil cooler. The center gear is particularly susceptible to wear under high‑temperature conditions.

• Listen for unusual noises from the pump area – Whining, growling, or clicking sounds from the hydraulic pump often indicate gear wear or bearing failure. If you hear unusual noises, investigate immediately – continued operation will cause catastrophic failure of the pump.

• Inspect the pump during scheduled maintenance – When the hydraulic pump is serviced, inspect the center gear for signs of wear: tooth pitting, spalling, scoring, or uneven wear patterns. Replace the gear if any damage is visible.

• Use only genuine OEM replacement gears – Aftermarket gears may not meet the same metallurgical and heat‑treatment standards as genuine Hitachi parts. A lower‑quality gear will wear faster and may fail prematurely, causing expensive pump damage.

• Keep the hydraulic system clean – When replacing the center gear or performing any pump service, ensure all components are cleaned thoroughly and the work area is free from contamination. Even a small amount of debris can cause rapid wear of precision‑ground gear teeth.

• Store spare gears properly – Keep center gears in their original packaging, in a dry, clean environment. Protect them from moisture and physical damage.