Thermostat Cover 8-97306461-2 8973064612 For ISUZU D-MAX TFR 4JH1 2012–2016 — Billet Aluminum Die-Cast, Grey, OEM-Grade Aftermarket, Direct Fit

8-97306461-2 8973064612 Thermostat Cover for ISUZU D-MAX TFR 4JH1 2012–2016 — Billet Aluminum Die-Cast, Grey, OEM-Grade Replacement, 25.5×18×7.5cm

✅ Product Description

The Thermostat Cover with OEM references 8-97306461-2 / 8973064612 is a verified replacement cooling-system component for ISUZU D-MAX (TFR/TFS) pickups equipped with the 4JH1 (3.0L) diesel engine, primarily covering the 2012–2016 model years. This cover is the upper housing cap that seals the thermostat cavity and forms the closed coolant circuit at the thermostat-housing interface, responsible for retaining the thermostat in position and preventing coolant leakage under operating pressure and temperature.

The part is manufactured from billet aluminum die-cast (铝坯压铸 / Billet-Aluminium Casting) in a grey finish, providing dimensional stability and corrosion resistance in the hot coolant environment. It is a brand-new component, not remanufactured, with actual dimensions of 25.5 × 18 × 7.5 cm and a reference warranty of 6 months from the supplying factory. The part is cataloged under the OKEIMT brand (model J05E) and is also listed under the ISUZU factory reference WW-DX0009.

• ✅ OE Reference Group Verified: 8-97306461-2 / 8973064612 is confirmed across Yishan Auto Parts (Slovenian, Serbian, Pakistani portals) as the factory number for the DMAX 4JH1 thermostat housing cap.-1

• ✅ Material Verified: Billet aluminum die-cast (铝坯压铸 / Billet-Aluminium Casting / Aluminium Druckguß) — confirmed by OKEIMT / Guangzhou Paqiben supplier listings.-12-19

• ✅ Dimensions Verified: Actual size 25.5 × 18 × 7.5 cm — confirmed by Yishan Auto Parts factory data across multiple language portals.-1

• ✅ Vehicle & Engine Coverage Verified: Confirmed for ISUZU D-MAX 4JH1, with the Jsgeling supplier explicitly listing DMAX 2012–2016 as the application window. Thai and Turkish suppliers confirm D-MAX (4JH) TFR 3000 applications.-9-14

• ✅ Temperature Resistance (Application-Level Reference): The Jsgeling listing for the 8973064612 thermostat assembly describes a reinforced nylon housing rated for 120°C+ operation with an 82°C±2°C opening thermostat. Note: The Jsgeling description refers to the thermostat assembly as a whole; the cover itself (8-97306461-2) is confirmed as billet aluminum by the OKEIMT supplier data. Confirm material and temperature rating against the original unit if a specific housing material is critical.-9

• ✅ Weight Reference: 1,000 g (Thai OEM parts listing for 8-97306461-2).-14

• ✅ Cross-Reference Density Verified: 8973064610 (OE number cited by Yishan), WW-DX0009 (factory model reference), and 8973064602 (related water outlet pipe reference in Korean catalog) are consistently grouped with the primary reference across multiple independent catalogs.-1-15

• ⚠️ Gasket Inclusion Not Confirmed: Public supplier listings for this cover do not clearly state whether a gasket is included. Confirm gasket inclusion at inquiry — a missing gasket means the vehicle cannot be returned to service until one is sourced.

✅ [Failure Symptoms — When to Replace]

• Coolant leak at the thermostat housing joint: Visible drips, dampness, or crusty residue (white/pink coolant crust) around the cover-to-housing interface — the most direct sign of a failed gasket or a warped/corroded cover sealing surface.

• Overheating or temperature fluctuation: A cover that does not seal correctly allows coolant loss or air ingress, disrupting thermostat operation and causing temperature instability, especially under load or in hot climates.

• Coolant residue on the engine block or under the vehicle: Dried coolant around the thermostat area indicates a slow weep that should be addressed before it becomes a sudden failure.

• Visible corrosion or pitting on the cover sealing surface: Aluminum covers can corrode at the coolant passage edges, preventing the gasket from sealing even when new.

• Cracked or deformed cover: Impact damage or over-torqueing of the mounting bolts can crack the aluminum casting, requiring replacement.

• Thermostat not seating properly: A distorted cover cavity can prevent the thermostat from sealing, causing continuous coolant bypass and extended warm-up times.

⚠️ Consequence of Ignoring Symptoms: A leaking or distorted thermostat cover on a 4JH1 engine can progress to coolant loss and overheating, risking head gasket failure or cylinder head warping on an aluminum-head common-rail diesel. On a working D-MAX pickup in commercial or agricultural service, a cover that costs a fraction of a head repair should be replaced at the first sign of seepage or seating failure.

✅ Vehicle & Engine Compatibility

Primary Confirmed Applications:

⚠️ Important Fitment Notes:

• Component scope must be confirmed first: This is the thermostat cover (cap) with an integrated coolant outlet passage. It is not the thermostat itself, not a standalone water outlet pipe (e.g., 8973064602), and not the complete thermostat housing body. Compare the original unit’s physical form — a cover with a sealing perimeter and outlet neck vs. a pipe with a hose neck — before ordering.

• 8-97306461-2 vs. 8973064610: The 8973064610 reference is cited by Yishan as the OE number for the thermostat housing cap, while 8-97306461-2 is the factory number. These are functionally interchangeable for the same cap position on the D-MAX 4JH1. Read the original unit’s marking where possible.

• Material ambiguity in catalog data: Some supplier descriptions for the broader 8973064612 thermostat assembly reference a reinforced nylon housing (rated 120°C+), while the cover-specific listings (OKEIMT, Yishan) confirm billet aluminum die-cast. Confirm the material against the original unit if a specific housing material is required — do not assume all listings describe the same physical component.

• Model year boundary: The Jsgeling listing explicitly ties 8973064612 to DMAX 2012–2016. Later D-MAX generations (2017+) may use a different cover specification. Do not assume interchangeability across model years without VIN confirmation.

✅ Features & Benefits

✅ Quality Control & Verification

Because this cover exists in a multi-reference family with catalog terminology inconsistencies (cover vs. pipe), confirming the physical form and sealing surface on the first sample is strongly recommended before bulk commitment.

✅ Installation & Maintenance Recommendations

⚠️ IMPORTANT: Cooling-system service requires a cold engine and proper coolant handling. Always refer to the ISUZU D-MAX 4JH1 workshop manual for the specific model. Improper installation can cause coolant leaks, air locks, and repeat overheating. Aluminum covers are sensitive to over-torqueing — use a torque wrench.

Installation Guidelines (Reference Only):

1. Confirm the required component first: Verify that the original unit is the thermostat cover with outlet passage, not a standalone water outlet pipe (8973064602) or the housing body. Compare the physical shape and sealing perimeter.

2. Cold engine only: Allow the engine to cool fully before opening the cooling system. Drain coolant to a level below the thermostat housing.

3. Remove the old cover: Unbolt the cover from the thermostat housing. Note the orientation of the outlet neck and any hose connection. Do not pry against the aluminum sealing surface.

4. Clean the mating surface: Remove all old gasket residue and corrosion from the housing face and the cover sealing surface. A clean, flat surface is essential for a leak-free seal.

5. Inspect the thermostat: With the cover removed, check the thermostat for correct operation. Replace if stuck open or closed.

6. Install the new cover with a new gasket: Seat a new gasket (confirm inclusion at inquiry) on the housing, position the 8-97306461-2 / 8973064612 cover, and insert the mounting bolts.

7. Torque in sequence: Tighten the cover bolts evenly in a cross pattern to the workshop manual specification. Do not over-torque aluminum castings — excessive torque distorts the sealing surface and causes leaks.

8. Reconnect the hose and refill coolant: Reconnect the upper radiator hose to the cover outlet neck (where applicable). Refill with the correct coolant mixture and bleed the system according to the ISUZU procedure.

9. Run and verify: Start the engine, bring it to operating temperature, and check for leaks at the cover joint. Confirm the temperature gauge stabilizes and the heater blows hot.

Maintenance Schedule:

• Inspect the cover joint at every coolant service or every 20,000–30,000 km — look for crusty residue or dampness.

• Replace the gasket whenever the cover is removed — gaskets are single-use compression seals.

• Flush coolant according to the manufacturer interval. Degraded coolant accelerates aluminum corrosion.

• Replace the cover if the sealing surface is pitted or warped — resurfacing an aluminum cover is not recommended for this application.

✅ Packaging & Supply

• Standard packing: Neutral carton or wooden case; customer-branded packaging available on request.

• Package contents: 1 × Thermostat Cover . Gasket, thermostat, and mounting bolts are not included unless explicitly stated — confirm exact package contents at inquiry.

• Set options: Cover only / cover + gasket set — specify at inquiry.

• Suitable for: ISUZU D-MAX / TFR 4JH1 cooling-system repair shops, diesel pickup fleet maintenance departments, spare parts distributors, and export wholesalers serving Southeast Asia, the Middle East, Africa, and Latin America.

• Related parts available: Thermostat, thermostat housing gasket, thermostat housing body, water outlet pipe (8973064602), and complete 4JH1 cooling-system kits.