858331 Valve Seat | Genuine Volvo Penta Part

🔧 Product Description

Genuine Volvo Penta valve seat in the standard size, weighing 0.025 kg and listed for 63 applications across TAMD, AD, D, TMD, TD and KAMD series engines - the widest fitment of the four valve seats listed here. It supersedes 838608. The 0.20 mm oversize seat is 858332; the published weights do not track the sizes, so order by the size marking and the measured bore rather than by mass.

🚤 Compatibility

• Engine Family: TAMD, AD, D, TMD, TD, KAMD, MD, KAD

Full model list at the end of this description.

⚙️ Key Features

• Standard size
• Supersedes 838608
• 0.025 kg
• 63 applications across six engine series

🔌 Function

Provides the hardened annular face in the cylinder head that the valve closes against to seal the combustion chamber.

⚠️ Common Signs of Failure

• Compression loss and hard starting on one cylinder
• Blowing or hissing heard at the valve on a compression test
• Valve clearances closing up between services
• Seat recessed, pitted or cracked on inspection
• Seat found loose in its counterbore

🛠️ Service Notes

• Order by the size marking, not by published weight - the graded seats here do not separate by mass
• If the counterbore has already been opened up, the 0.20 mm oversize 858332 is the seat to fit
• Check the valve guide for wear at the same time

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 858331 → Supersedes 838608

OEM / Related Numbers

• 838608 earlier number superseded by this part

📦 Condition

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

🔎 Full Model Compatibility

Typically suits:

• Volvo Penta TAMD31L-A, TAMD31M-A, TAMD31P, TAMD31P-A, TAMD31S, TAMD31A, TAMD31B, TAMD31D
• Volvo Penta TAMD41B, TAMD41D, TAMD41H-A, TAMD41H-B, TAMD41M-A, TAMD41P-A, TAMD41P, TAMD41A
• Volvo Penta AD31, AD31B, AD31D, AD31D-A, AD31L-A, AD31P-A, AD31XD
• Volvo Penta AD41B, AD41D, AD41L-A, AD41P-A, AD41A, AD41BJ
• Volvo Penta TMD31A, TMD31B, TMD31D, TMD31L-A
• Volvo Penta TMD41A, TMD41B, TMD41D, TMD41L-A
• Volvo Penta D41B, D41D, D41L-A
• Volvo Penta KAD42A, KAD42B, KAD42P-A
• Volvo Penta KAD44P, KAD44P-B, KAD44P-C
• Volvo Penta KAMD42A, KAMD42B, KAMD42P-A
• Volvo Penta KAMD43P, KAMD43P-A, KAMD43P-B
• Volvo Penta KAMD44P-B, KAMD44P-C, KAMD44P-A
• Volvo Penta TAMD42WJ-A, TAMD42B
• Volvo Penta KAD300-A
• Volvo Penta KAD32P
• Volvo Penta KAD43P-A
• Volvo Penta KAMD300-A
• Volvo Penta MD31A
• Volvo Penta TD31ACE