Description
Zeus A275L Vortec Alternator with Regulator
The highest power output alternator in its size/class.
Features:
- Engineered for High Energy Production.
- Suitable for Marine, RV, Military, and Commercial applications.
- Rapidly charges large battery banks.
- Coolest operating temperatures for increased performance.
- Runs 8 – 20% cooler than incumbent alternators due to: Heat shedding coatings, Rectifier located on housing exterior, Dual cooling fans, and OEM Components.
- It is optimized for performance at idle speeds.
- Reduces the need for a generator by creating additional power with your engine.
- Unleash peak performance with E-Coat/Cerakote. Our advanced coating absorbs less heat, keeping the A275L cooler. This translates to more amperage for sustained periods.
- Use an ARCO Zeus Bluetooth alternator regulator or lithium battery charging for maximum performance.
- SAE J1171 Certified.
- Made in the U.S.A.
Technical Specifications:
- Voltage – 12v
- Field Type – P
- Rotor Poles – 16
- Stator Size – 138mm
- Frame Size – Large
- Weight – 14.9 lbs/6.7 kg
- Regulation – Internal/External (Internally regulated with adaptor for optional external regulation.)
- Output Voltage – 14.1v (Default)
- Finish – (Black) Cerakote or E-coating
- Cut-In RPM – 1,061 Alternator RPM
- Maximum Alt RPM – 19,000
- Battery Post – M8 Thread Post, Side Mount
- Standard Pulley – 49K6 (6-groove, 49mm)
- Pulley Mount – 17mm diameter shaft, 25mm long, threaded M17 x 1.5
- Pulley Hardware – M17 x 1.5 x 24mm nut, w/ 18mm ID x 29mm OD washer (Included)
- Diodes – 6 positive, 6 negative, 50A Rated, Avalanche
- Max Output (Cold, 9,000 RPM) – 311 Amps
- Sustained Cruising Output (Hot, 6,000 RPM) – 227 Amps
- Sustained Idle Output (Hot, 3,000 RPM) – 198 Amps
- Max Continuous Operating Temperature – 110°C / 230°F
Mounting Application:
- Replaces Mando-type alternators using Vortec/GM pad mounting feet. (Found on many Mercruiser and Volvo Penta 3.0GLM, 3.0GLP, 4.3GXi, 5.7GiL, 5.7GXiL Marine Engines.) (GM Blocks)
Quick Guide (pdf)

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