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Description
The Sierra Mercruiser Thermostat Kit 18-3668D is designed for reliable cooling system performance on 1983 and newer GM V-6 and V-8 marine engines. With a 142°F temperature rating, it helps maintain optimal operating temperature for efficient engine operation. This kit replaces common Mercruiser and aftermarket thermostats for a dependable, direct-fit upgrade.
Sierra Mercruiser Thermostat Kit - 18-3668D Item # 1780968
Description
Features:
- Fits: 1983 & newer GM V-6 & V-8 engines with standard cooling
Specifications:
- Temperature Rating: 142°F
Replaces:
- GLM:
- 13390
- Mallory:
- 9-43150
- Mercruiser Stern Drive:
- 807252Q4
- 807252T4