ARCO Marine Zeus A275L 12V 311A Single Foot Alternator, 1"-2"

The ARCO Marine Zeus A275L is a high-output 12V alternator engineered for marine, RV, military, and commercial applications. Designed for rapid charging of large battery banks, it delivers a maximum cold output of 311 Amps and maintains 198 Amps of sustained output at idle. This unit features advanced thermal management, including dual cooling fans, a heat-shedding Cerakote and E-Coat finish, and an externally mounted rectifier to ensure cooler operation and consistent performance.

Key Features:

• Fits most domestic styles with a 1" or 2" single mounting foot, such as Motorola and Prestolite configurations
• Optimized for performance at low idle speeds
• Runs 8-20% cooler than standard alternators to support sustained high-amperage output
• Supports both internal and external regulation (adapter required for external)
• SAE J1171 certified and made in the U.S.A.
• Max operating temperature: 110°C (230°F)
• Includes M17 x 1.5 pulley hardware

Technical Specifications:

• Voltage: 12V
• Max Output: 311 Amps (Cold, 9,000 RPM)
• Sustained Output: 227 Amps (Hot, 6,000 RPM)
• Weight: 14.9 lbs
• Pulley: 49K6 (6-groove, 49mm)
• Shaft: 17mm diameter
• Battery Post: Side-mount M8 thread
• Manufacturer Part Number: 4029