Briggs & Stratton (B&S) 691564/693469/808106 12V 15-tooth steel-tooth V-Twin twin-cylinder engine permanent magnet direct-drive starter motor

12V permanent-magnet direct-drive starter motor engineered for 16-24 HP V-twin lawn and grounds equipment. The hardened 15-tooth steel gear and heavy-duty Bendix handle the compression shock of large-displacement twins, while sealed construction keeps dust and moisture out of the motor.

OEM and Search References

• Primary reference: Briggs & Stratton 691564 / 693469 / 808106
• Substitute reference: Briggs & Stratton 843258 / 844717 / 846451 / 592407; John Deere M143512; Arrowhead SBS0044 / 410-22060; J&N 410-22060; Lester 5776 / 5777 / 5776N
• Equipment reference: Briggs & Stratton Vanguard and Intek 16-24 HP V-twin engines on John Deere LT166 / LT170 / LTR166 / SST16 / SST18, Cub Cadet GT2521 / LT2180, Arctic Cat SBS 1000, and Toro Greensmaster / Sand Pro / Infield Pro grounds machines
• Buyer search terms: Briggs & Stratton 691564 starter motor, 693469 starter, 808106 starter, Vanguard V-twin starter, 15 tooth steel gear starter, John Deere LT166 starter, Toro Greensmaster 3150 starter

Reference Specifications

• System voltage: 12V, permanent-magnet direct-drive (PMDD) design
• Pinion: 15 teeth, hardened alloy steel, for steel or cast-iron ring gears
• Power: 0.7-1.0 kW; overall length approximately 185 mm; housing approximately 97 mm
• Mounting: 2-bolt side mount, centres approximately 68-70 mm; single M6 / M8 power stud
• Rotation: counter-clockwise (CCW), viewed from the pinion end
• Important identification note: steel 15-tooth gear and side-mount flange identify this unit. It does not interchange with the 16-tooth nylon-gear starters used on single-cylinder engines (490420 / 497595), and it is not a solenoid-shift design - the Bendix is inertia-driven.

Fitment and Purchase Checks

Catalog-listed equipment: Vanguard / Intek 16-24 HP V-twin engines and the mowers, grounds machines and utility vehicles listed above. Confirm engine model and type code, existing starter number, voltage, pinion tooth count (15 teeth), gear material, rotation, mounting centres (68-70 mm), terminal type and physical dimensions before purchase. Check the ring gear material too: this steel gear suits steel or cast iron, and must not be paired with a ring gear worn to a sharp profile. Exact fitment on unlisted models has not been verified and is omitted.

For Agricultural Buyers and Distributors

This listing is organized for outdoor power equipment and grounds-care procurement teams, repair shops and parts distributors searching by engine model and OEM reference. It covers the 16-24 HP V-twin range used on commercial grounds machines and large garden tractors, where starter failure takes a machine out of a maintenance schedule rather than a weekend. For quotation, specify the engine model, old-part number, required quantity and destination. Confirm price, stock, package quantity and delivery terms with the seller before placing a purchase order.

Product Positioning

Briggs & Stratton Vanguard and Intek V-twins (16-24 HP) drive large garden tractors, grounds machines and utility vehicles that work to a schedule - a Toro Greensmaster that will not start holds up an entire green, and a Deere LT166 that will not start blocks a homeowner's season. Twin-cylinder starters fail faster than single-cylinder units because every start fights higher compression, so the gear and Bendix take repeated impact. This starter reproduces the original 15-tooth steel gear, side-mount flange at 68-70 mm centres and single power stud exactly, so a workshop replaces the unit as a whole. For distributors, one SKU serves the commercial grounds market and the large-tractor market at once, cross-listed to John Deere M143512 and Arrowhead SBS0044.

How It Works: Power and Engagement

The unit is a permanent-magnet direct-drive (PMDD) design with an inertia Bendix: a copper-wound armature spins inside high-temperature permanent magnets, and the 15-tooth steel gear rides on a helical sleeve on the armature shaft. When the key applies voltage to the main stud, the armature accelerates, inertia throws the gear forward into mesh with the ring gear, and the engine is cranked; once it fires, the gear retracts. There is no external solenoid to burn out - a single stud carries the current and the housing provides earth. Rotation is counter-clockwise viewed from the pinion end, matching the Vanguard flywheel, and the 2-bolt side mount fixes the gear-to-ring-gear clearance as the factory did.

Materials and Durability

• Drive gear: 15-tooth hardened alloy steel, for steel and cast-iron ring gears and high-shock engagement.
• Bendix: heavy-duty helical drive sized for 16-24 HP compression, not the lighter single-cylinder mechanism.
• Magnets: high-temperature permanent magnets, stable under sustained heat soak after mowing.
• Windings: pure copper wire for low resistance and strong torque at low battery state of charge.
• Housing: sealed, corrosion-resistant 97 mm shell that keeps dust, moisture and clippings out of the brush area.

Problems It Solves

Twin-cylinder machines usually arrive with one of four complaints. First, a labored crank that barely turns the engine over, from weak magnets or a tired Bendix in the original. Second, a metallic grind on engagement when the gear no longer meshes fully with a worn ring gear. Third, a starter that spins freely without cranking - a stripped gear or sheared Bendix. Fourth, intermittent no-start from arced commutator surfaces after seasons of dust. Replacing the complete unit clears all four in one step. One caution before ordering: this 15-tooth steel unit will not fit single-cylinder engines that use 16-tooth nylon gears, and a steel gear should not be run against a ring gear already worn to sharp points.

Replacement Value for Shops and Distributors

For repair shops, one correctly matched starter returns a grounds machine or garden tractor to service the same day, with no drilling, tapping or wiring changes in between. For dealers and distributors, the numbers work: 50-unit minimum order, 7-30 day lead time, 12-month warranty, and unit pricing well below OEM supply channels, leaving room for margin at competitive shelf price. Production follows ISO 9001, IATF 16949 and CE practices, and consistent cross-references to Lester 5776, John Deere M143512 and Arrowhead 410-22060 keep ordering by catalog number straightforward and returns low.