807252Q5 Thermostat Kit Sierra part no 18-3647

Sierra 18-3647 Thermostat Kit for Mercury MerCruiser Outboards (71°C)

Ensure optimal engine temperature regulation and prevent overheating with the Sierra 18-3647 Thermostat Kit, designed as a direct replacement for Mercury MerCruiser outboard engines. This high-quality marine thermostat kit includes all necessary gaskets and seals for an efficient and long-lasting installation.

Key Features:

✔ Premium Marine-Grade Quality – Designed for durability and reliability in harsh marine environments.
✔ Maintains Optimal Engine Temperature – 160°F (71.1°C) thermostat ensures proper cooling for enhanced performance and longevity.
✔ OEM Replacement – Direct replacement for Mercury/MerCruiser 807252Q5, 807252T5, Sierra 18-3647D, Mallory 9-43157.
✔ Complete Kit – Includes thermostat, O-ring, and all necessary gaskets for an easy installation.
✔ Wide Compatibility – Suitable for a variety of MerCruiser 3.0L, 4.3L, 5.0L, 5.7L, 7.4L, and 8.2L engines.

Thermostat Kit Contents:

🔹 18-3649 – 160°F (71.1°C) Thermostat (Replaces Mercury 807252-2)
🔹 18-2844 – Thermostat Cover Gasket (Replaces Mercury 27-48818-1)
🔹 18-2552 – Thermostat Cover Gasket (Replaces Mercury 27-33179-2)
🔹 18-2553 – Thermostat Cover Gasket (Replaces Mercury 27-47510)
🔹 18-7173 – O-Ring (Replaces Mercury 25-30224)
🔹 18-2917 – Thermostat Housing Gasket (Replaces Mercury 27-53045-1 & 27-33918)

Compatibility:

This thermostat kit is suitable for various MerCruiser inboard and sterndrive engines, including:

MerCruiser Models:

✅ 3.0L TKS L4
✅ 4.3L / 4.3LX / 4.3LH EFI (Alpha, Bravo)
✅ 5.0L EFI (Alpha, Bravo)
✅ 5.7L / 5.7L EFI / 5.7L MIE
✅ 350 Mag / 350 Mag MPI / 350 Mag EFI Ski
✅ 7.4L / 7.4L MPI / 7.4L MIE
✅ 8.2L / 8.2L MPI / 8.2L MIE
✅ 502 EFI / 502 Mag MPI
✅ Scorpion Ski
✅ 454 Mag MCM / Ski

(For detailed serial number ranges, refer to the full compatibility list above.)

Why Choose Sierra 18-3647 Thermostat Kit?

🔹 Reliable Engine Protection – Prevents engine overheating, ensuring smooth operation.
🔹 Easy Installation – Includes all necessary gaskets and seals for a hassle-free setup.
🔹 Meets or Exceeds OEM Standards – Direct replacement for Mercury and MerCruiser thermostats.
🔹 Marine-Grade Materials – Built for long-lasting durability in marine environments.

🛒 Order now and keep your MerCruiser outboard engine running at peak performance with this high-quality thermostat kit!