Balmar Dual V Pulley 2.7" (69mm) x 1/2" (13mm) DeepV, 17mm Bore

High-Output Alternator Dual Deep-V Pulley for 6 & XT Series

High-amperage alternators place significant mechanical load on engine drive systems. When generating substantial electrical power for auxiliary battery banks, standard single-belt pulleys often suffer from belt slippage, premature wear, and frustrating belt squeal. This precision-machined Dual Deep-V Pulley is engineered to resolve these mechanical bottlenecks, providing a robust power transmission interface for heavy-duty charging systems.

Designed as the standard Dual Vee setup for 6 Series and XT Series alternators, this pulley distributes the rotational load across two parallel 1/2" (approx. 13mm) belts. By doubling the surface contact area, it maximises belt grip and ensures reliable torque transfer from the engine crankshaft to the alternator rotor, even under peak electrical demand.

Precision Engineering for Demanding Environments

Unlike standard cast pulleys that can suffer from balance issues and rapid groove wear, this component is machined from high-grade steel and finished with a protective gold-coloured zinc plating. The precision-machined 17mm centre bore ensures a concentric, vibration-free fit on standard 17mm alternator shafts, reducing radial load on the alternator's front bearings and extending the overall service life of your charging unit.

• Dual Deep-V Grooves: Twin 1/2" (approx. 13mm) deep-V channels sit the belts deeper into the pulley, increasing side-wall contact to minimise slippage under heavy electrical loads.
• Corrosion-Resistant Finish: Heavy-duty zinc plating protects the steel construction against rust, salt spray, and oxidation, making it well-suited for marine engine bays and off-road 4WD applications.
• Optimised Drive Ratio: The 2.7" (approx. 69mm) outer diameter is calculated to maintain efficient alternator rotor speeds across a wide RPM range, supporting strong output even at low engine idle.
• Direct Series Compatibility: Purpose-built as the standard Dual Vee configuration for 6 Series and XT Series high-output alternators.
• Balanced Steel Construction: Solid steel fabrication prevents flexing and warping under high tension and elevated engine bay temperatures.

Reducing the Risk of Drive System Failure

In remote off-grid touring, commercial transport, or marine vessels, a snapped or slipping alternator belt can quickly lead to depleted battery banks and immobilised equipment. Inferior pulleys with poor surface finishes or imprecise groove angles accelerate belt glazing and heat build-up. By upgrading to a dedicated deep-groove dual pulley, you reduce the required tension per belt while increasing total friction. This lowers the mechanical stress on both the water pump and alternator bearings while preventing sudden drive belt failure.

Ideal Applications

This 17mm bore dual pulley is essential for custom installations and direct replacements where high-output alternators are utilised:

• Marine propulsion and auxiliary generator engines requiring dual-belt redundancy
• 4WD touring vehicles and expedition trucks running high-capacity 12V or 24V lithium battery systems
• Commercial, agricultural, and industrial machinery fitted with 6 Series or XT Series alternators
• Custom engine conversions requiring reliable twin 1/2" (approx. 13mm) V-belt alignment

Upgrade Your Alternator Drive System

Ensure your charging system delivers consistent power without the risk of belt slip. Fit this heavy-duty Dual Deep-V Pulley to your 6 or XT Series alternator for dependable mechanical performance in harsh operating conditions.