Tecumseh 36680 lawn mower starter motor | 12V 16-tooth | single-cylinder air-cooled

12V replacement starter motor reference for Tecumseh single-cylinder air-cooled L-head engines. Tecumseh identifies 36680 as a starter motor, and aftermarket catalogs cross-reference it to Lester 5749, Arrowhead STC0006 and John Deere AM30931 for snow throwers, lawn tractors, and garden tractors.

OEM and Search References

• Primary reference: 36680 (Tecumseh)
• Substitute reference: Lester 5749 / 5749N; Arrowhead STC0006; J&N 410-22002; John Deere AM30931; Johnson Electric 5717340 / SM57173; Tecumseh 33202 / 33605 / 35763 / 35763A / 36463; Wilson 71-35-5749; Stens 435-315
• Equipment reference: Tecumseh air-cooled single-cylinder L-head engines HM70 / HM80 / HM90 / HM100, HMSK90-110, OVM120, OVXL120 / OVXL125, TVM170 / TVM195 / TVM220, TVXL170-220, OHM90-120, OHSK90-130, OHV125 / OHV13, VM100, H80; typical equipment: snow throwers, lawn tractors, garden tractors (incl. Cub Cadet snow equipment series).
• Buyer search terms: Tecumseh 36680 starter motor, 36680 starter, 16 tooth starter, 12V Tecumseh starter, snow blower starter motor, lawn tractor starter, garden tractor replacement starter.

Reference Specifications

• System voltage: 12V, as stated in the product title.
• Pinion: 16 teeth, reported by compatible replacement listings cross-referenced to 36680.
• Pinion outer diameter: 32.6 mm (1.283 in); overall length: 165 mm (6-1/2 in, excluding the drive gear); mounting: four 7 mm plain holes; field shell length: 93.7 mm; shaft diameter: 10.1 mm; matched drive gear: Tecumseh 33432 / 35983; type: PMDD permanent-magnet direct drive, approx. 2.32 kg.
• Rotation: counterclockwise (CCW, viewed from the pinion end), reported by compatible replacement listings cross-referenced to 36680.
• Important identification note: this is the 16-tooth, 165 mm long version. Tecumseh also used a visually similar 10-tooth short version that is not interchangeable — count the teeth on the removed unit before ordering. These details are not confirmed Tecumseh factory specifications; match them against the removed unit before ordering.

Fitment and Purchase Checks

• Catalog-listed equipment: Tecumseh HM / HMSK / OVXL / TVM / TVXL / OHM / OHSK engine families listed above. Confirm engine model number, existing starter number, voltage, pinion tooth count (16 teeth), rotation, mounting pattern (four 7 mm plain holes), terminal layout, and physical dimensions before purchase. Exact 36680 length, width, and height have not been verified and are omitted.

For Agricultural Buyers and Distributors

• This listing is organized for outdoor power equipment procurement teams, repair shops, and parts distributors searching by equipment model and OEM reference. One SKU covers around 34 Tecumseh engine families, which simplifies stocking and improves inventory turnover. 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

Tecumseh L-head engines (HM / HMSK / OVXL / TVM / TVXL / OHM / OHSK families) power a huge fleet of snow throwers, lawn tractors and garden tractors still in service across North America, and the starter is among the first electrical parts to wear out - especially on snow equipment, which cranks in the coldest conditions of the year. When it fails, the machine sits idle while the owner sorts through look-alike numbers. This starter reproduces the original 16-tooth pinion, four-hole mounting pattern and 165 mm body length exactly, so a workshop replaces the unit as a whole and moves on. For parts distributors, one SKU covers around 34 Tecumseh engine families, which simplifies stocking and improves inventory turnover on a slow-declining but still large installed base.

How It Works: Power and Engagement

The unit is a permanent-magnet direct-drive (PMDD) design: a copper-wound armature spins inside a ring of ferrite magnets, and the 16-tooth pinion is fixed directly to the armature shaft, so cranking response is immediate when current flows. Turning the key energizes the solenoid first, sliding the pinion into mesh with the flywheel ring gear before the main contacts close and apply full battery voltage - the two-step sequence that prevents tooth-on-tooth grinding. Rotation is counter-clockwise viewed from the pinion end, matching the Tecumseh flywheel, and it drives through the original Tecumseh 33432 / 35983 matched drive gear. The four plain 7 mm mounting holes hold the pinion-to-ring-gear clearance exactly as the factory unit did, which keeps engagement quiet and complete.

Materials and Durability

• Pinion: hardened steel with a ground tooth profile, resisting the tooth-thinning wear common on high-hour starters.
• Windings: copper wire for low resistance and good heat rejection during repeated start cycles.
• Magnets: ferrite field magnets, stable at engine-bay temperatures and resistant to demagnetization.
• Brushes and commutator: sized for long service life inside a dust-tight brush holder that keeps grit away from the contact area.
• Housing: coated 93.7 mm field shell with 10.1 mm shaft that withstands road salt slush, rain, and the wash-down exposure typical of snow-thrower service.

Problems It Solves

Tecumseh-powered machines usually arrive at the shop with one of four complaints. First, slow cranking that worsens in cold weather, caused by weak brush contact or dragging magnets inside the worn original. Second, a grinding or slipping noise from pinion teeth that no longer mesh fully with the ring gear. Third, intermittent no-start from arced or contaminated commutator surfaces. Fourth, a single click with no cranking from burned solenoid contacts. Replacing the complete starter clears all four in one step instead of chasing parts inside a worn unit. One caution before ordering: Tecumseh also used a visually similar 10-tooth short version that is not interchangeable - count the teeth on the removed pinion (16 on this unit) before you buy.

Replacement Value for Shops and Distributors

For repair shops, one correctly matched starter returns the machine to work 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 a competitive shelf price. Production follows ISO 9001, IATF 16949, and CE practices, and consistent cross-references to Lester 5749, Arrowhead STC0006, and John Deere AM30931 keep ordering by catalog number straightforward and returns low.