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Thermostat Housing Assembly Kit for MAG MerCruiser 4.3 6.3L MPI 350 863457A2
$659.99
Sale price
$659.99
Regular price
Available to Order
This Thermostat Housing Assembly Kit is a replacement thermostat housing compatible with MAG MerCruiser 4.3-6.3L MPI 350 engines and matches OEM Part# 863457A.
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I needed a forklift part and wasn’t sure which one fit. They asked for the model and serial number, got back to me quickly, and made sure I ordered the right one. Really helpful.
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Product Overview
This Thermostat Housing Assembly Kit is a direct replacement for MAG MerCruiser 4.3L to 6.3L MPI 350 engines. It controls engine coolant flow to maintain optimal operating temperature. Designed for marine mechanics and boat owners, this kit includes the housing and necessary components for a complete repair.
Key Features & Performance
- Precision-machined housing for leak-free seal
- Includes gasket and fasteners for easy installation
- Compatible with MerCruiser 4.3L, 5.0L, 5.7L, 6.2L, and 6.3L MPI 350 engines
- OEM replacement part number 863457A ensures fitment
- Durable construction withstands marine engine conditions
- Restores proper thermostat operation for efficient cooling
Fitment & Compatibility
- MAG MerCruiser 4.3L MPI 350
- MAG MerCruiser 5.0L MPI 350
- MAG MerCruiser 5.7L MPI 350
- MAG MerCruiser 6.2L MPI 350
- MAG MerCruiser 6.3L MPI 350
Common Uses
- Replacing failed thermostat housings on MerCruiser marine engines
- Overheating repairs on inboard and sterndrive boats
- Routine maintenance of cooling system components
- Upgrading to OEM-spec housing for reliability
Technical Specifications
- Part Number(s): 863457A
- Compatible Engines: MerCruiser 4.3-6.3L MPI 350
Frequently Asked Questions
Q: Is this housing kit compatible with MerCruiser 4.3L Alpha One? A: Yes, it fits MerCruiser 4.3L MPI 350 engines, including Alpha One and Bravo drives.
Q: Does the kit include a thermostat? A: This is a thermostat housing assembly kit; it includes the housing and gasket but the thermostat itself may be sold separately.
Product appearance and specifications may vary slightly by batch. Compatibility may vary by serial number. Verify fitment before purchase.