20489008 Cylinder Head | Genuine Volvo Penta Part

🔧 Product Description

D7A-TA cylinder head catalogued through engine serial 10705992. Later new and exchange/remanufactured cylinder-head alternatives are listed for serial and service comparison. Application note: Catalogue application for 20489008 is shown through engine serial 10705992; confirm the engine product and serial number before ordering.

🚤 Compatibility

Typically suits:

• Volvo Penta D7A-T
• Volvo Penta D7A-TA
• Volvo Penta D7C-TA

• Engine Family: D
• HP Range: Approximately 250 HP
• Year Range: Approximately late 1990s-2000s
• Serial Range: SN-10705992

⚙️ Key Features

• OEM cylinder-head casting and machined combustion interfaces
• Supports the original valves, guides, injector and coolant/oil passages
• Serial-dependent alternatives are identified in the cross-reference section
• Requires inspection of mating surfaces and renewal of specified gaskets and seals
• Cylinder-head fasteners and tightening procedure must follow the workshop specification
• Engine type: 7 L six-cylinder turbocharged diesel

🔌 Function

Seals the top of the cylinders and carries the valve train, injector and internal oil/coolant passages required for combustion and heat transfer.

⚠️ Common Signs of Failure

• Low compression, hard starting or persistent cylinder misfire
• Coolant or engine-oil leakage at the cylinder-head joint
• Combustion gas entering the cooling system or recurring coolant pressurisation
• Cracked casting, damaged valve seats, worn guides or injector-bore damage
• Overheating or repeated cylinder-head-gasket failure

🛠️ Service Notes

• Check the head for cracks and check the head and block faces for flatness with a straight edge before assembly, and have any doubt about the face or the valve seats resolved before the gasket goes on
• Clean the gasket faces with care and without scoring them — do not attack an aluminium face with abrasive discs or scrapers, and keep debris out of the bores, coolant passages and bolt holes
• Always use a new head gasket, and tighten in the stages, sequence and torque-plus-angle steps given in the workshop manual for your engine, with the threads and mating faces clean and lubricated exactly as that manual specifies
• Head bolts on modern engines are angle-tightened and stretch permanently, so renew them wherever the manual calls for it rather than reusing them
• Refill and bleed the cooling system properly, then run the engine and carry out any retightening or valve clearance recheck the manual requires after the first running period

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 20489008 → Supersedes 20412326

OEM / Related Numbers

• 20405999 earlier number superseded by this part
• 21037874 later new cylinder head
• 20459962 inlet valve seat
• 20459963 exhaust valve seat
• 20405897 valve guide
• 11700347 compression spring

OEM Reman Alternatives

• 3803664 remanufactured cylinder head
• 3801397 exchange cylinder head

📦 Condition

• Genuine Volvo Penta part
• Brand new
• Supplied in original or equivalent packaging