21509621 Roller Kit | Genuine Volvo Penta Part

🔧 Product Description

Genuine Volvo Penta Twin Disc MG5170 Flexible Coupling Roller Kit - Part Number: 21509621

A genuine eight-piece rubber roller set for the flexible coupling used with Twin Disc MG5170 marine transmissions.

⚙️ Key Features

• Eight matched rubber rollers

• For MG5170 connecting-component assemblies

• Reduces torsional vibration and transient driveline load

• OEM hardness and dimensional control

📋 Kit Contents

• 8 × rubber coupling roller - serviced under kit 21509621; individual rollers are not separately numbered

🔄 Supersession & Cross Reference

OEM Supersession Chain:

• 21509621 current roller-kit reference

OEM / Related Numbers:

• Twin Disc MG5170 connecting components

• Related flywheel, companion flange and coupling hardware are ratio and engine-installation specific

Aftermarket / Verified Equivalents:

• No direct aftermarket equivalent verified

• Twin Disc coupling-service alternatives must be matched by coupling model, roller count, dimensions and elastomer hardness

🚤 Compatibility

Used on large Volvo Penta marine propulsion packages fitted with a Twin Disc MG5170 reversing gear, commonly D13 and D16-class installations.

• HP Range: approximately 700HP-1,000HP+

• Year Range: approximately 2000s-2010s

• Serial Range: MG5170 transmission and coupling serial controlled

🔌 Function

The rollers transmit torque through the flexible coupling while cushioning firing pulses, gear engagement shock and small alignment changes.

Common signs of failure:

• Rubber is cracked, flattened, oil-softened or missing

• Coupling knocks or rattles at idle

• Vibration increases during gear engagement

• Roller debris is found in the coupling housing

• Excessive coupling backlash develops

📦 Condition

• Genuine Volvo Penta part

• Brand new

• Supplied in original or equivalent packaging