Balmar 12V 120A 60 Series Alternator, 3.15in Saddle Mount, Isolated Ground (No Pulley)

High-Output 60 Series 12V 120A Isolated Ground Alternator

Upgrade your marine or off-grid mobile power generation with the 60 Series 12V 120A Alternator. This high-output alternator delivers reliable, high-amperage charging to keep your auxiliary battery banks topped up. Featuring a 3.15in (Approx. 80mm) Hitachi-style dual-foot saddle mount, it is a high-performance upgrade for engines with this mounting style, typical for Yanmar, Westerbeke, Lehman and Perkins-Sabre engines.

Why Choose an Isolated Ground Alternator?

Standard automotive alternators use the engine block and chassis as the electrical return path. In marine vessels and specialised composite-body vehicles, this can lead to severe galvanic corrosion, stray current issues, and interference with sensitive onboard electronics. This 60 Series unit features a dedicated Isolated Ground (IsoGrd) terminal. By isolating the negative return path from the alternator case and engine block, it significantly reduces the risk of stray current corrosion on hulls, propellers, and underwater metal fittings, whilst providing a cleaner, more stable electrical circuit for your charging system.

Key Features and Benefits

• High-Output 120A Charging: Provides substantial current at 12V to rapidly replenish deep-cycle house batteries, supporting high-draw appliances such as inverters, refrigeration, and navigation systems.
• Isolated Ground Architecture: Protects marine vessels and specialised vehicles from galvanic corrosion and stray electrical currents.
• 3.15in (Approx. 80mm) Saddle Mount: Hitachi-style dual-foot mount, typical for Yanmar, Westerbeke, Lehman and Perkins-Sabre engines.
• Customisable Drive Setup (No Pulley Included): Supplied bare to allow precise matching with your engine's existing belt profile, preventing belt slip and premature wear.
• Dual Fan Cooling: Compact, small-case 6-Series design with dual fan cooling and a high airflow frame.

Customise Your Belt Drive: Compatible Pulley Options

Please note that this alternator is supplied without a pulley. High-output alternators place increased mechanical load on engine drive belts. By selecting the exact pulley required for your engine setup, you ensure optimal belt wrap, correct drive ratios, and reduced slippage. This unit accepts the following 17mm bore pulleys:

• B-61-0020: Pulley, Dual V 2.7in (Approx. 68.6mm) x 1/2in (Approx. 12.7mm) DeepV, 17mm Bore
• B-61-0070: Pulley, K-6 2.45in (Approx. 62.2mm) (Serpentine 6-Rib), 17mm Bore
• B-1310: Pulley, K-8 2.4in (Approx. 61mm) (Serpentine 8-Rib), 17mm Bore, Short (STD)

Designed for Recreational Applications

When cruising off-grid or operating in remote locations, engine run-time efficiency is critical. Standard factory alternators quickly derate as engine bay temperatures rise, resulting in slow charge times. Balmar designs its 6-Series alternators for recreational applications and describes them as ideal for modest charging upgrades. Its Smart Ready internal regulator may be sufficient where battery loads are relatively small and the engine runs frequently. For larger deep-cycle battery banks, or where the engine runs less often (as on most sailing vessels), pair it with a Balmar ARS-5 or Max Charge multi-stage regulator.

Ready to Upgrade Your Charging System?

Configure your ideal marine or mobile charging solution today. Pair this 60 Series 12V 120A Alternator with your required 17mm bore pulley and enjoy dependable, isolated-ground power generation on your next voyage.