21087443 Valve Seat | Genuine Volvo Penta Part

🔧 Product Description

A genuine Volvo Penta standard-size intake valve-seat insert for selected D5 and D7 cylinder heads. The hardened press-fit seat provides the precision sealing surface for the inlet valve and transfers combustion-chamber heat from the valve into the cylinder head. Correct interference fit, installed depth and concentric machining are essential during cylinder-head overhaul.

🚤 Compatibility

Typically suits:

• Volvo Penta TAD560VE
• Volvo Penta TAD561VE
• Volvo Penta TAD734GE
• Volvo Penta TAD752GE
• Volvo Penta TAD753GE
• Volvo Penta TAD754GE
• Volvo Penta TAD765VE
• Volvo Penta TAD764VE
• Volvo Penta TAD763VE
• Volvo Penta TAD762VE
• Volvo Penta TAD761VE

• Engine Family: TAD

⚙️ Key Features

• Standard-size hardened intake valve-seat insert
• Precision seat material resists impact, heat and recession
• Provides the concentric sealing face required for correct compression
• Transfers heat from the inlet valve into the cylinder head
• Requires professional cylinder-head machining and final seat-angle finishing
• Engine type: D5/D7-series inline diesel cylinder head

🔌 Function

Forms the durable, accurately machined sealing surface against which the inlet valve closes. It preserves cylinder compression, valve heat transfer and correct airflow into the combustion chamber.

⚠️ Common Signs of Failure

• Low compression or cylinder leakage through the intake valve
• Valve-seat recession and reduced valve clearance
• Pitting, burning or cracking of the seating face
• Loose insert or loss of interference fit in the cylinder head
• Repeated valve damage caused by an off-centre or incorrectly machined seat

🛠️ Service Notes

• Seat inserts are an interference fit in the head, so the counterbore has to be clean, round, flat and square before a new seat goes in; normal practice is to chill the insert and warm the head so it drops into place rather than forcing it
• This is machine-shop work — the seat must be cut concentric with the valve guide after installation, so check or renew the guides at the same time and cut the seat angles once the insert is secure
• Inspect the head casting for cracks and for a pounded or spread counterbore before committing to a new seat; a seat that has come loose has usually damaged its pocket
• Use the interference fit, insert size and seat angles specified for your engine rather than any general figure, as they differ between heads
• Check each valve on its finished seat for an even contact band right the way round, and confirm valve position and any permitted recession against the workshop manual for your engine

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 21087443 → Supersedes 20833927

OEM / Related Numbers

• 20833927 earlier number superseded by this part

Other-Brand OEM Numbers

• Renault Trucks 7420833927
• Deutz/KHD 04900631
• Deutz/KHD 04905938
• TRW Engine Components: 92-22019

Aftermarket / Verified Equivalents

• OE Germany: 04 0123 201300 / 040123201300
• LASO: 9805 3109
• SLP: VS-443

📦 Condition

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