Original ISUZU 4JJ1 Engine Thermostat 8980170272 for Excavator

This high-precision engine thermostat assembly is an original high-quality thermal management core component of Isuzu, with the original core part number 8-98017027-2 (8980170272). This high-end dual valve temperature control unit is specially designed for various high standard hydraulic excavators equipped with the classic Isuzu 4JJ1 four cylinder direct injection turbocharged engine, such as Hitachi ZX120-3, ZX130-5G, Sumitomo, Case and other core star models in the 12-13 ton industry. The product is based on first principles optimization of high-sensitivity paraffin wax temperature sensing body architecture, accurately regulating the physical critical point of switching between large and small cycles, ensuring that the core thermodynamic system of the engine is always in a low entropy, high-efficiency absolute stable temperature zone. The physical dimensions of the product packaging are approximately 90mm × 85mm × 80mm, with an overall net weight of approximately 0.25kg.

"Extreme cleaning and valve orientation (core pit avoidance): After disassembling the old parts, the joint surface between the thermostat seat and cover must be thoroughly wiped clean of old gasket residue and kept extremely dust-free. When installing a new thermostat, it is necessary to ensure that the shaking valve/exhaust valve (Jiggle Valve) on the valve body is aligned with the scale directly above the housing, so that the cooling system can discharge residual air without obstruction when injecting water, and prevent local high temperature breakdown caused by air resistance.

It is strictly prohibited to abuse glue and torque fastening: during installation, it is necessary to replace the original brand new sealing ring forcefully. It is strictly forbidden to apply any liquid sealant on the surface of the sealing ring to prevent excess squeezed glue from circulating with the coolant and sticking to the main valve core. The fixing bolts of the shell must be tightened symmetrically and in stages using precision torque wrenches, strictly following the original factory torque standards, to prevent slight deformation of the cast aluminum shell.

Low pressure exhaust and thermodynamic verification: After filling with brand new coolant, ignite for the first time and maintain low-speed idle running for 15-20 minutes. Closely observe the water temperature gauge until the main valve is fully opened, the temperature of the upper and lower water pipes reaches absolute thermal equilibrium, and no bubbles are discharged. Confirm that the thermodynamic operating system has restored absolute order before applying normal operating loads."