This 12V 40-Amp Alternator is a high-performance replacement specifically engineered for Vetus marine diesel engines. Designed to withstand the harsh conditions of marine environments, this unit features a corrosion-resistant finish and high-temperature internal components to ensure reliable battery charging and electrical system support.
DIRECT REPLACEMENT: This 40A unit is a direct-fit replacement for the original STM3931/STM1655 alternators used on Vetus engines.
Key Features
✔ Direct Fit: No modifications required for Vetus M-Series.
✔ Marine-Ready: Sealed bearings and internal protection.
✔ Tacho Terminal: Includes "W" terminal for tachometer connection.
✔ Output: 40 Amps for modern marine electronics.
Technical Specs
Voltage
12V
Amperage
40A
Rotation
CW (Clockwise)
Pulley Type
1-Groove (V-Belt)
Regulator
Internal (IR)
Fan Type
Internal (IF)
Compatibility / Fitment Guide
Engine Model
Application
Notes
Vetus M2.C5
Marine Diesel
1998-Onwards
Vetus M2.D5
Marine Diesel
1998-Onwards
Vetus M3.09
Marine Diesel
All Models
Mitsubishi L2A / L2E
Industrial/Marine
Base Engine Fitment
OEM Cross Reference
Vetus
STM3931, STM1655, STM1243
Mitsubishi
A7TA0171, A7TA0171B, A1T25271
Wilson
90-27-3278
Lester
20563
Questions & Answers
Is this a genuine original part?
This is a premium quality 4Drive aftermarket replacement part, manufactured to meet or exceed original equipment (OE) standards for fitment and performance.
Does this match my original alternator?
This is a 40A unit, matching the original 40A alternator on Vetus M-Series engines. If your original unit is rated 50A, check the part number before ordering.
Does it include the pulley?
Yes, this alternator comes complete with a single-groove V-belt pulley installed and ready for mounting.
Note: Please verify your original part number against the references above. For more assistance, visit 4drive.co.uk.
