20405796 Pulley | Genuine Volvo Penta Part

🔧 Product Description

Genuine Volvo Penta alternator pulley used on early TD520GE and TD720GE 14 V 55 A and 28 V 35 A alternator arrangements. The 14 V application is used through serial number 1025582.

🚤 Compatibility

Typically suits:

• Volvo Penta TD720GE
• Volvo Penta TD520GE
• Volvo Penta TAD720GE
• Volvo Penta TAD720VE
• Volvo Penta TAD721VE
• Volvo Penta TAD722VE
• Volvo Penta TAD520GE
• Volvo Penta TAD520VE

• Engine Family: TD, TAD
• Serial Range: SN-1025582

⚙️ Key Features

• Alternator drive pulley for early production
• Confirmed on 14 V 55 A and 28 V 35 A alternators
• 14 V application through serial number 1025582
• Used with the original alternator fan, nut and V-belt
• Pulley grooves must match the specified belt
• Engine type: Volvo Penta 5- and 7-litre industrial diesel

🔌 Function

Transfers belt drive to the alternator at the specified speed ratio.

⚠️ Common Signs of Failure

• Belt squeal or slip
• Worn or chipped pulley grooves
• Loose pulley nut
• Reduced charging output from belt slip

🛠️ Service Notes

• Inspect the belt running surfaces before fitting — a pulley with glazed, scored, pitted or rust-roughened grooves will chew through a new belt in very little running time
• Check that the pulley runs true and that its bearing or bush turns smoothly with no roughness or side play; fit a new belt whenever a pulley is changed
• Confirm that every pulley in the drive lies in the same plane and that the belt profile matches each groove — misalignment shows up as belt dust, squeal or a worn belt edge and will destroy a new belt quickly
• Fit onto a clean, dry, burr-free shaft or hub face and tighten the retaining fasteners in the sequence and to the figures given in the workshop manual for your engine
• Turn the engine over by hand before starting to confirm the belt is fully seated in every groove and that nothing fouls, then recheck belt tension after the first running period

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 20405796 → Supersedes 20405799

OEM / Related Numbers

• 20405799 earlier number superseded by this part
• 20405794 - early 14 V 55 A alternator
• 20571565 - later 14 V 55 A alternator
• 20441521 - pulley nut
• 978515 - related early V-belt
• 20405804 - early tensioner

📦 Condition

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