859944 Piston Ring Kit | Genuine Volvo Penta Part

🔧 Product Description

Genuine Volvo Penta piston ring kit in the 0.50 mm oversize, from the Engine group, weighing 0.041 kg and listed for 9 applications across the TMD, MS, TAMD and MD engine series. It consolidates six earlier numbers — 3580776, 3580774, 861365, 861364, 861585 and 861587 — some of which were catalogued as piston kits rather than as ring sets, so an engine documented under one of those numbers should be checked for what is actually needed before ordering.

🚤 Compatibility

Typically suits:

• Volvo Penta TMD22A
• Volvo Penta TMD22B
• Volvo Penta TMD22P-C
• Volvo Penta MS2B-A
• Volvo Penta TAMD22P-B
• Volvo Penta MD22
• Volvo Penta MD22A
• Volvo Penta MD22L
• Volvo Penta MD22P

• Engine Family: TMD, MS, TAMD, MD

⚙️ Key Features

• 0.50 mm oversize
• Consolidates six earlier numbers, including some listed previously as piston kits
• 0.041 kg
• 9 applications across TMD, MS, TAMD and MD engines
• 0.50mm (Volvo assembly listing)
• 4 used per assembly
• Also supersedes Volvo part numbers 859942 and 859943

🔌 Function

Seals the piston to the bore, controlling compression above the piston and oil below it, and carries heat from the piston crown into the cylinder wall.

⚠️ Common Signs of Failure

• Blue smoke from the exhaust, worst on load or after idling
• Oil consumption rising with no external leak
• Crankcase pressure blowing oil out of the breather or the filler
• Compression down across one or more cylinders
• Rings found stuck, gummed or broken in their grooves on strip-down

🛠️ Service Notes

• An oversize ring set only suits a bore that has been machined to match — measure the bore before ordering rather than assuming the oversize
• Check the ring groove clearance and the end gap in the actual bore before assembly
• Some of the numbers this kit replaces covered pistons as well as rings, so confirm what the rebuild needs

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 859944 → Supersedes 3580776

OEM / Related Numbers

• 861365 earlier number superseded by this part
• 861364 earlier number superseded by this part

📦 Condition

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