20482687 Voltage Regulator | Genuine Volvo Penta Part

🔧 Product Description

Alternator voltage regulator for the D5A/D7A charging-system family, used with the specified alternator configuration and pulley/belt arrangement. 28 V alternator voltage regulator used in the applicable Volvo Penta charging-system configuration.

🚤 Compatibility

Typically suits:

• Volvo Penta D5A-B TA
• Volvo Penta D5A-T
• Volvo Penta D5A-TA
• Volvo Penta D7A-B TA
• Volvo Penta D7A-T
• Volvo Penta D7A-TA
• Volvo Penta D7C-B TA
• Volvo Penta D7C-TA
• Volvo Penta MD2010
• Volvo Penta MD2010B

• Engine Family: D, MD
• HP Range: Approximately 250 HP
• Year Range: Approximately late 1990s-2010s, depending on engine and installation

⚙️ Key Features

• 28 V regulator for the specified three-phase alternator configuration
• Controls alternator field current and charging-system voltage
• Maintains stable battery charging under changing speed and electrical load
• Protects batteries and connected equipment from sustained overvoltage
• Must be matched to the alternator identification and wiring arrangement
• Engine type: Four- and six-cylinder Volvo Penta diesel

🔌 Function

Monitors and controls alternator output to maintain the charging system near its specified voltage across engine speed and electrical load.

⚠️ Common Signs of Failure

• Battery overcharging or undercharging
• Charging warning lamp remains illuminated
• Unstable 28 V charging voltage or flickering electrical equipment
• Repeated battery discharge, overheating or electrolyte loss
• Alternator output remains outside specification after wiring, ground and belt checks

🛠️ Service Notes

• Isolate the batteries at the main switch and disconnect the negative lead before working on the charging circuit, and never disconnect a battery while the engine is running
• Rule out the simple causes before condemning a regulator — a slack or glazed drive belt, corroded or loose battery and alternator connections, a poor engine-to-battery earth, or a tired battery all produce the same symptoms
• Check the brushes and slip rings while the regulator is off; a worn brush set gives the same low or erratic output
• Fit clean and dry, seat any insulating washers and bushes in their original order so nothing bridges across them, and tighten the terminals firmly without crushing them
• Measure charging voltage at the battery with the engine running once the regulator is fitted, and compare it with the value specified for your engine and battery type

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 20482687 → Supersedes 23642811 → Supersedes 20549901

OEM / Related Numbers

• 23642811 earlier number superseded by this part
• 20549901 earlier number superseded by this part
• 881668 alternator
• 20571644 later alternator
• 968933 V-belt

Other-Brand OEM Numbers

• Bosch: F 04R 320 367 - 28 V alternator regulator

OEM Reman Alternatives

• 3801327 remanufactured alternator
• 3803882 remanufactured later alternator

Aftermarket / Verified Equivalents

• SRP: VR-82687

📦 Condition

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