AIPICO Marine Thermostat Kit for Mercury/Mariner 4-Stroke 8–90HP — 140°F (60°C) Thermostat with Gasket 27-824853

The AIPICO Marine Thermostat Kit (825212T02 / 855676A1) is a complete aftermarket replacement for Mercury Mariner 4-stroke outboards that stabilizes engine temperature at 140°F (60°C) and includes gasket 27-824853.

If your Mercury 4-stroke outboard has been running hot, producing irregular warm-up times, or shows signs of coolant flow issues, this tested AIPICO kit offers a direct-fit thermostat solution. Designed for manual mounting on most Mercury/Mariner 4-stroke engines from 8HP up to 90HP, the kit arrives pre-tested and ready to install. It restores consistent operating temperature control so the engine runs closer to its intended performance range without expensive OEM downtime.

How does this thermostat kit maintain proper engine temperature?

The thermostat opens and closes at a calibrated 140°F (60°C) to regulate coolant flow through the engine’s cooling passages. By closing during cold starts it promotes faster warm-up; by opening as temperature rises it permits coolant circulation to prevent overheating. The included gasket ensures a tight seal at the mounting surface to avoid leaks that reduce cooling efficiency.

• Calibrated to open at 140°F / 60°C for consistent regulation
• Manual-mount design fits common Mercury/Mariner housings
• Included 27-824853 gasket prevents coolant leaks at installation
• Factory testing before shipment verifies proper operation

Will this part fit my Mercury or Mariner outboard motor?

This AIPICO kit is engineered as a direct replacement for many Mercury Mariner 4-stroke models in the 8HP–90HP range that use part numbers 825212T02, 855676A1, 825212, 855676003, or 825212001. Compatibility depends on your specific engine year and housing design, so check part numbers or compare the old thermostat unit for a match. When in doubt, compare dimensions and mounting points prior to purchase.

• Replaces OEM numbers: 825212T02, 855676A1, 825212, 855676003, 825212001
• Recommended for Mercury/Mariner 4-stroke 8–90 HP models
• Compare your existing thermostat and gasket to confirm fit
• Technical compatibility check advised for non-standard engine years

What does the kit include and how reliable is it?

The package contains the thermostat assembly and gasket 27-824853 (also referenced as 27-8248531 in some lists). Each kit is inspected and tested before shipment to ensure the thermostat responds at the correct temperature and the gasket seals properly. Using a tested aftermarket kit can provide reliable performance when OEM parts are unavailable or more costly.

• Thermostat assembly matched to 140°F / 60°C activation
• Gasket 27-824853 included for proper sealing
• Pre-shipment testing to confirm operation and sealing
• Aftermarket alternative for budget-conscious repairs

How difficult is installation and what should I prepare?

Installation is a straightforward mechanical replacement typically done at the water pump or thermostat housing location. Basic hand tools, a clean mounting surface, and proper torque on fasteners are all that’s required. Replace the gasket and clean mating surfaces to ensure a leak-free seal, and follow manufacturer torque specs when tightening bolts.

• Basic tools: wrench set, gasket scraper, torque wrench recommended
• Clean mating surfaces thoroughly before installing new gasket
• Follow engine manual torque and reassembly sequence
• Inspect cooling passages and impeller while access is open

Who is this for: The AIPICO Marine Thermostat Kit is intended for boat owners, marine mechanics, and DIYers who operate Mercury/Mariner 4-stroke outboards (8–90HP) and need a reliable, tested replacement thermostat with gasket. It’s a practical solution for routine maintenance, mid-season repairs, or when restoring proper cooling function without sourcing OEM parts. If you value a direct-fit, pre-tested aftermarket part that helps maintain consistent engine temperature, this kit is a suitable and cost-effective option.