1543861 Valve Seat | Genuine Volvo Penta Part

🔧 Product Description

This is a genuine Volvo Penta valve seat for the cylinder head of TWD, TID, TAMD and TAD 16-litre series marine and industrial diesel engines. It is supplied in the standard size designation "Std D", which identifies the specific standard outer diameter grade of the seat ring and must be matched to the seat bore machined in the head. Ordering a different size grade will prevent correct seating and press fit, so confirm the required designation before purchase.

🚤 Compatibility

Typically suits:

• Volvo Penta TWD1620G
• Volvo Penta TWD1630G
• Volvo Penta TID162AG
• Volvo Penta TID162AGP
• Volvo Penta TID162AP
• Volvo Penta TID162APB
• Volvo Penta TAMD162A
• Volvo Penta TAMD162B
• Volvo Penta TAMD162C
• Volvo Penta TAMD162C-B
• Volvo Penta TAD1630G
• Volvo Penta TAD1630GE
• Volvo Penta TAD1631GE
• Volvo Penta TAD1631G

• Engine Family: TWD, TID, TAMD, TAD
• HP Range: Approximately 500-770 HP
• Year Range: Approximately late 1980s-2005

⚙️ Key Features

• OEM Volvo Penta part number 1543861
• Supplied as size designation Std D (standard, grade D)
• System group: Engine
• Net weight approximately 0.043 kg
• Fits TID162, TAMD162, TWD1620G/1630G and TAD1630/1631 series diesel engines
• Single valve seat ring - quantity required depends on cylinder head configuration
• Engine type: 16.1L inline-six turbocharged/aftercooled diesel
• 50.08mm (Volvo assembly listing)
• 12 used per assembly

🔌 Function

The valve seat forms the hardened sealing surface in the cylinder head against which the intake or exhaust valve face closes, sealing the combustion chamber during compression and firing. It also conducts heat away from the valve head into the cylinder head.

⚠️ Common Signs of Failure

• Loss of compression, hard starting or misfire on one cylinder
• Visible pitting, burning or recession of the seat sealing face
• Valve seat leakage found during a leak-down or vacuum test after lapping
• Loose or dropped seat insert causing severe valve and piston damage
• Excessive valve stem protrusion or lost valve clearance from progressive seat recession

🛠️ 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

• 1543973 (oversize service seat; machining required and not a drop-in substitution)

OEM / Related Numbers

• 1543872 inlet valve spring
• 1543046 inlet valve-spring washer

Aftermarket / Verified Equivalents

• Atex: 611-43861
• DT Spare Parts: 2.10842
• OE Germany: 030123162000

📦 Condition

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