Thermostat Kit – Fits Mercury/Mariner V6 Outboards 135-200HP (Replaces 75692Q2)

$46.99

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Product Details

This Thermostat Kit – Fits Mercury/Mariner V6 Outboards 135-200HP (Replaces 75692Q2) is designed for a range of Mercury and Mariner V6 outboard engines. It is compatible with 135-150HP models with serial number A9046446 and higher, 175HP models with serial number C100861 and higher, and 200HP models with serial number 6435503 and higher.

This kit serves as a direct replacement for Mercury/Quicksilver part numbers 75692Q2, 75692, and 75692Q03.

Engineered for direct replacement, simplifying installation.
Kit includes two 143°F thermostats and two matching rubber gaskets.
Designed for marine V6 outboard engine applications.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand	Part Number	Notes
Mercury/Quicksilver	75692Q2	Primary Replacement
Mercury/Quicksilver	75692	Interchangeable
Mercury/Quicksilver	75692Q03	143°F Version

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury/Mariner engines, verify your model and check that your engine's serial number falls within the specified range.

Brand	Model	Rated HP	Stroke	OEM Part No.	Notes
Mercury/Mariner	V6	135	2-Stroke	75692Q2	S/N A9046446 and higher
Mercury/Mariner	V6	150	2-Stroke	75692Q2	S/N A9046446 and higher
Mercury/Mariner	V6	175	2-Stroke	75692Q2	S/N C100861 and higher
Mercury/Mariner	V6	200	2-Stroke	75692Q2	S/N 6435503 and higher

Technical Specs

Product Type: Thermostat Kit
Installation: Direct replacement; see owner's manual for instructions
Temperature Rating: 143°F (61.7°C)
Quantity in Kit: 2 thermostats + 2 rubber gaskets
Dimensions: Height: 2.5 in; Width: 10.0 in; Length: 15.5 in
Weight: 0.06 kg (0.13 lb)
Application: Marine V6 Outboard Engines
OEM Part Number: Mercury/Quicksilver 75692Q2
Other Technical Attributes: Kit includes two thermostats and two rubber gaskets (one for each thermostat)

What’s in the Box

2 x Thermostat (Replaces 75692Q2)
2 x Rubber Gasket

Installation Notes

Ensure the engine is completely cool and disconnect the battery.
Locate the thermostat housings on the engine block.
Place a drain pan below and carefully remove the housing covers to drain coolant.
Remove the old thermostats and rubber gaskets. Note their orientation.
Clean the mating surfaces of the housing and cover, removing any old gasket material or corrosion.
Install the new thermostats and gaskets in the correct orientation.
Reinstall the housing covers and tighten the bolts to the manufacturer's specified torque.
Reconnect all hoses and refill the cooling system with the recommended coolant.
Start the engine and check for leaks around the housings as it warms up.

Troubleshooting & FAQ

How do I know if my outboard needs a new thermostat?

Common signs of a failing thermostat include engine overheating at idle or low speeds, or the engine running too cold and not reaching its optimal operating temperature. You may also notice erratic temperature gauge readings.

What's the difference between the 143°F and 147°F thermostats?

The temperature rating indicates when the thermostat begins to open. The 143°F version in this kit is specified for most listed models. A higher rating like 147°F may be used in colder climates to help the engine warm up faster, but it's critical to use the temperature specified by your engine's manufacturer to ensure proper performance.

Will this kit fit an engine outside the listed serial number range?

We can only guarantee fitment for the serial number ranges provided. Using this kit on other models is not recommended, as internal engine components can vary significantly even on models with the same horsepower rating.

How often should outboard thermostats be replaced?

For preventative maintenance, it is advisable to inspect and consider replacing thermostats every 2-3 years or 200-300 hours of use, especially if operating in saltwater. Always refer to your owner's manual for specific service intervals.

Why is it sold as a kit of two?

V6 outboard engines like the compatible Mercury/Mariner models use two thermostats—one for each cylinder bank. It is critical to replace both at the same time to ensure balanced engine cooling and performance.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
This is an aftermarket replacement, not an OEM component.
Professional installation is recommended for safety and performance.

About Sea Sierra

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