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Gaskets (Tohatsu)

Thermostat Cap Gasket 346-01032-0

Brand: Tohatsu

SKU: 346-01032-0

$6.00
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The Genuine Tohatsu 346-01032-0 Thermostat Cap Gasket is designed for selected Tohatsu 2-stroke and 4-stroke outboard motors. Installed between the thermostat housing and cover, this genuine OEM gasket helps maintain a watertight seal within the engine cooling system. Ideal for thermostat replacement, cooling system maintenance and repairing coolant leaks, it provides a factory-specified replacement to support reliable cooling-water circulation and engine temperature control.

Key benefits

Key Benefits

  • - Genuine Tohatsu OEM replacement gasket.
  • - Helps prevent cooling-water leakage around the thermostat cover.
  • - Suitable for selected 2-stroke and 4-stroke outboard motors.
  • - Designed to match compatible factory thermostat housing surfaces.
  • - Ideal for thermostat servicing and replacement.
  • - Helps maintain cooling-system sealing integrity.
  • - Replaces several earlier OEM gasket part numbers.
  • - Supplied individually for convenient servicing.

Specifications & Dimensions

  • - Manufacturer: Tohatsu
  • - OEM Part Number: 346-01032-0
  • - OEM Ordering Number: 346010320M
  • - OEM Description: Thermostat Cap Gasket
  • - Product Type: Thermostat housing cover gasket
  • - Installation Location: Between thermostat cap and engine mating surface
  • - Application: Outboard engine cooling system
  • - Engine Compatibility: Selected 2-stroke and 4-stroke models

Compatible Tohatsu Outboards

  • 2-Stroke – 9.9HP to 18HP
  • - M9.9D2 – 9.9HP
  • - M15D2 – 15HP
  • - M18E2 – 18HP
  • - MX18E2 – 18HP
  • 2-Stroke – 25HP to 40HP
  • - M25C3 – 25HP: Selected model configurations.
  • - M30A4 – 30HP: Listed in OEM parts records.
  • - M40C – 40HP: Later thermostat housing configuration only.
  • M40C serial-number restriction: Engines with serial numbers 94363 and below use a different gasket and cannot be assumed compatible. The parts supplier advises that the older gasket is unavailable and that conversion to the later configuration requires different housing components.
  • 4-Stroke – 8HP to 9.8HP
  • - MFS8A3 – 8HP
  • - MFS9.8A3 – 9.8HP
  • 4-Stroke – 9.9HP to 20HP
  • - MFS9.9C – 9.9HP
  • - MFS15C – 15HP
  • - MFS20C – 20HP
  • - MFS15E – 15HP
  • - MFS20E – 20HP
  • 4-Stroke – 25HP to 30HP
  • - MFS25D – 25HP
  • - MFS30D – 30HP

Compatible Mercury & Mariner Outboards

  • Mercury 4-Stroke
  • - 15HP – 2020–2021: Serial number 0R833820 onwards.
  • - 20HP – 2020–2021: Serial number 0R833820 onwards.
  • Mariner 4-Stroke
  • - 15HP – 2020–2021: Selected models within the supplier's stated serial-number range.
  • - 20HP – 2020–2021: Selected models within the supplier's stated serial-number range.
  • Mercury / Mariner 2-Stroke
  • - 25HP – 2006–2017: Selected international models with serial numbers beginning 0N0.
  • - 30HP – 2006–2017: Selected international models with serial numbers beginning 0N0.

Cross-Reference & Replacement Part Numbers

  • Genuine Tohatsu OEM
  • - 346-01032-0 – Current thermostat cap gasket.
  • - 346010320M – Current OEM ordering number.
  • - 350-02032-0 / 350020320M – Earlier OEM part, superseded by 346010320M.
  • - 3H6-01032-0 / 3H6010320M – Earlier OEM part, superseded by 346010320M.
  • Mercury / Mariner Cross-References
  • - 27-853702005 – Published Mercury/Mariner equivalent.
  • - 853702005 – Alternative reference without prefix.
  • - 18-60920 – Published aftermarket cross-reference.

Signs the Thermostat Cap Gasket Needs Replacing

  • - Cooling-water leakage around the thermostat housing.
  • - Visible deterioration or cracking.
  • - Torn or damaged gasket material.
  • - Gasket compressed or permanently deformed.
  • - Corrosion around the thermostat cover.
  • - Water escaping from the thermostat cap mating surface.
  • - Gasket damaged during thermostat removal.
  • - Thermostat housing being dismantled for servicing.

Important Fitment Information

  • - Confirm the exact engine model and serial number before ordering.
  • - This is a genuine Tohatsu OEM gasket, not an aftermarket replacement.
  • - Supersedes earlier OEM references 350-02032-0 and 3H6-01032-0.
  • - Check thermostat cap and housing compatibility.
  • - M40C engines with serial numbers 94363 and below require special attention because they use an earlier gasket configuration.
  • - Do not reuse a damaged or compressed thermostat gasket.
  • - Remove old gasket material carefully without damaging the mating surfaces.
  • - Inspect the thermostat cap for corrosion, distortion or cracking.
  • - Ensure mating surfaces are clean before installation.
  • - Tighten thermostat cap bolts according to the manufacturer's service manual.
  • - Do not assume compatibility with every engine of the same horsepower.

Shipping

Ships Australia-wide