ISUZU 6HK1 Water Pump 1-13650133-0 for Hitachi ZX330 OEM Fit

Water Pump Assembly 1-13650133-0 / 1136501330 — a verified OEM-fit engine cooling pump for the ISUZU 6HK1 diesel engine, used across Hitachi ZX330 / ZX350 / ZX400 / ZX500 excavators, JCB JS330, and other construction machinery.

This water pump is the core circulation element of the engine cooling system. It drives coolant continuously through the engine water jacket, radiator, and heater circuit, carrying away combustion heat and maintaining the engine within its optimal operating temperature range.

The water pump is typically driven by the engine via a belt or gear. An internal impeller rotates, generating centrifugal force that draws coolant from the inlet and discharges it under pressure through the outlet, creating forced circulation.

The 6HK1 is a heavy-duty diesel engine for construction machinery, operating continuously under high load, dust, and vibration. The pump's bearing, mechanical seal, and water seal are the primary wear points. Once the seal fails or the bearing seizes, the consequences range from coolant leakage and noise to complete loss of circulation, rapid overheating, cylinder scoring, and catastrophic engine failure.

This pump features an iron/aluminum housing, with internal impeller and seal components matched to original specifications for stable cooling performance under continuous construction duty.

Replace the water pump when any of these symptoms appear:

• Continuous coolant drip from the weep hole — the most direct sign of mechanical seal failure; initially a seep, potentially progressing to a steady leak.
• Abnormally high engine temperature or frequent overheating — corroded or broken impeller, or belt slip, causing insufficient coolant circulation.
• Pump bearing noise (hum, whine, or metallic grinding) — bearing wear or lubrication failure, potentially leading to shaft seizure and belt breakage.
• Pulley wobble or abnormal belt wear — excessive bearing clearance causes pulley runout, accelerating belt and groove wear.
• Coolant seepage at the pump housing joint — aged housing gasket or cracked housing.
• No heater output or excessive radiator top-to-bottom temperature differential — an indirect sign of poor coolant circulation.

Based on FridayParts & Dizel-Detal data.

📌 Fitment Verification: To ensure 100% accurate matching, please provide the machine model, serial number (S/N), or engine number before ordering. We will verify it through the ISUZU/Hitachi global EPC system.

1. Preparation: Drain coolant. Remove the belt, fan, radiator hoses, and other components obstructing pump removal.
2. Removal: Remove the pump mounting bolts and extract the old pump. Clean the pump mounting surface on the engine block, removing old gasket residue.
3. Inspection: Inspect the mounting surface for corrosion, scoring, or distortion. Check the belt, tensioner, and fan clutch condition.
4. Installation: Install a new gasket/O-ring and position the new pump. Torque the bolts to specification in the correct sequence.
5. Reassembly: Install the belt, fan, and hoses. Adjust belt tension to specification.
6. Filling & Bleeding: Fill with the specified coolant mixture. Start the engine, idle, and thoroughly bleed the system (via the thermostat housing bleed screw or repeated fill/run cycles).
7. Leak Check & Load Test: Inspect the weep hole, hose connections, and mounting surface for leaks. Perform a load test to confirm stable coolant temperature.

• Daily / Every shift: Check coolant level; observe the weep hole for drips.
• Every 500 hours or per manual: Inspect belt tension and wear; check pump bearing for abnormal noise.
• Every 2,000 hours or per manual: Replace coolant; flush the cooling system.
• When weep hole dripping, abnormal temperature, or bearing noise is detected: Stop the machine and inspect; replace the pump if necessary.

• Standard Packaging: Anti-rust oil + VCI film + neutral carton/wooden case.
• Custom Packaging: Neutral box, color box, or customer-branded packaging.
• Suitable For: Construction machinery repair shops, ISUZU/Hitachi parts distributors, mining and fleet maintenance centers.
• Supply Capacity: Stable batch supply with batch-level quality reports available.
• MOQ: 1 PCS