21132989 Main Bearing Kit | Genuine Volvo Penta Part

🔧 Product Description

A standard-size crankshaft main-bearing shell package for the compact Volvo Penta D1 and early D2 marine diesel family. The crankshaft journals and cylinder-block bearing bores must be measured before standard-size bearings are selected.

🚤 Compatibility

Typically suits:

• Volvo Penta D1-30
• Volvo Penta D1-30B
• Volvo Penta D1-30F

• Engine Family: D
• HP Range: 30 HP
• Year Range: Approximately 2004 onward, dependent on engine version

⚙️ Key Features

• Standard-size crankshaft main-bearing set
• Used on compact D1 / D2 marine diesel engines
• Replaces earlier Volvo reference 3884512
• Precision matched bearing shells
• Crankshaft measurements are mandatory before installation
• Engine type: Volvo Penta compact 3-cylinder and 4-cylinder naturally aspirated marine diesel

📋 Kit Contents

• 1 x complete standard-size main-bearing shell package - supplied under 21132989
• Individual upper and lower shells are not separately itemised in the public Volvo Penta kit listing
• Thrust components and undersize bearings are not confirmed as included and must be selected separately where required

🔌 Function

Supports the crankshaft in the cylinder block, maintains the specified lubricating-oil film and transfers combustion loads into the main-bearing saddles.

⚠️ Common Signs of Failure

• Low engine oil pressure after the lubrication system has been checked
• Deep crankshaft knock or rumble under load
• Copper-coloured or bearing-metal particles in the oil or filter
• Crankshaft journal clearance exceeds the workshop limit
• Bearing shells are scored, overheated, fatigued or contaminated

🛠️ Service Notes

• Have the crankshaft journals measured before ordering so the kit matches the journal size — standard and reground shells are not interchangeable, and neither is a mixed set
• Fit the shells dry behind: clean the saddles and caps, wipe the shell backs, and never oil, grease or scrape the back of a shell, which stops it shedding heat and can let it move in the housing
• Check that each locating tang drops into its notch and the shell sits flush, and keep grooved, plain and flanged halves where the workshop manual for your engine puts them
• Oil the running and thrust faces, refit each cap in its original position and direction, and tighten in the manual's sequence to the torque and angle it specifies, renewing the bolts where they are single-use
• Check running clearance and crankshaft endfloat by the method in the manual and confirm the crank turns freely by hand before the sump goes back — and establish why the old bearings failed, because most repeat failures are oil supply or dirt rather than the bearings

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 21132989 → Supersedes 3884512

OEM / Related Numbers

• 3884512 earlier number superseded by this part
• 119613 Olsson Parts catalogue cross-reference

Aftermarket / Verified Equivalents

• CROM: 111598 standard main-bearing set
• Olsson Parts: 119613 cross-reference
• Recmar: RM21132989

📦 Condition

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