24V 4kW LTO, Isolated Ground, 49mm K6 Pulley Part# 4402

Unified Core Specifications
System Voltage: 24V Nominal
Technology Type: Low Turn-On (LTO)
Maximum Output: ~144 Amps
Grounding: Isolated Ground (prevents galvanic corrosion)
Included Pulley: 49mm K6 (6-Groove Serpentine)
Shaft Diameter: 17mm
Regulation Type: External Regulation Only
Protective Finish: Corrosion-resistant black E-coating.

Model 4402 Configuration
Part Number: 4402
Mounting Footprint: 3.15-inch Dual Foot (DF315)
Primary Compatibility: Yanmar engines and common marine propulsion systems
Max Nominal Power: 4.2 kW
Idle Performance: 1.4 kW (~51 Amps Hot at 3,000 alternator RPM)

Installation Instructions for 24V 4kW Marine AlternatorPhase
1: Pre-Installation & Safety
Disconnect Batteries: Turn off all battery switches. Disconnect the negative terminals of both starting and house banks.
Verify Alignment: Ensure the 49mm K6 pulley aligns with the engine crankshaft pulley to prevent premature belt wear.
Inspect Belts: Use a high-quality, heavy-duty K6 serpentine belt capable of handling a 4kW load.
Phase 2: Mechanical Mounting
Position Alternator: Place the alternator into the engine's dual-foot (DF315) mounting bracket.
Insert Pivot Bolt: Slide the main pivot bolt through the dual feet. Leave it finger-tight to allow movement.
Attach Tension Arm: Align the adjustment ear with the engine tensioner arm or brackets.
Torque Hardware: Once the belt is tensioned to specification, tighten the pivot bolt and adjustment bolt to engine manufacturer torque ratings.
Phase 3: Electrical Wiring
Positive Output (B+): Connect a heavy-gauge cable from the rear battery post directly to the positive distribution bus or battery switch.
Isolated Ground (B-): Run a matching heavy-gauge ground cable from the dedicated isolated ground terminal to the engine block ground or main negative bus. Do not rely on the chassis mount for grounding.
Field Control: Route the field wire from your external smart regulator to the field terminal on the alternator plug.
Stator/Tachometer: Connect the stator output wire to your engine tachometer input if required for RPM sensing.
Phase 4: System Integration & Testing
Connect Regulator: Plug the wiring harness into the external regulator. Ensure the temperature sensors are attached to both the alternator frame and the battery bank.
Reconnect Batteries: Reattach all negative battery terminals and turn on the main battery switches.
Program Regulator: Configure the external smart regulator with the correct charging profile for your specific battery chemistry.
Engine Test: Start the engine at idle. Verify that the alternator wakes up via the LTO function and check for smooth belt operation without vibration.