KPALAG MerCruiser Thermostat Kit for V6 & V8 4.3–8.2L (160°F) Brass/Stainless with Housing Sleeve & Gaskets

KPALAG's thermostat kit is a ready-to-install replacement for MerCruiser V6 and V8 engines (4.3L–8.2L, 1987–2016) that opens at 160°F and includes a brass/stainless thermostat, housing sleeve, and multiple gaskets.

This complete kit supplies the core cooling control component plus the sealing parts needed to service MerCruiser GM-based marine engines. Built from brass and stainless-steel materials for corrosion resistance and predictable operation, the thermostat begins to open at 160°F to help maintain engine operating temperature. The package also contains a housing sleeve and a set of three layered fiber gaskets designed for oil and heat resilience, so you can replace the whole assembly without sourcing separate seals.

How does this thermostat affect boat engine temperature control?

The thermostat regulates coolant flow between the engine and the heat exchanger by opening at a precise temperature. That controlled flow helps the engine warm up efficiently and prevents overcooling once operating temperature is reached. Using a replacement that matches OE specifications helps maintain factory-calibrated performance.

• 160°F opening temperature for consistent thermostat actuation
• Brass and stainless-steel construction resists corrosion in marine environments
• Matches replacement numbers like 807252Q5 and 806922 for compatibility

What parts are included and why are the gaskets important?

The kit comes with the thermostat, a housing sleeve, one housing gasket, and three additional thermostat gaskets. Gaskets provide reliable sealing between the thermostat housing and engine passages, preventing coolant or oil leaks that can compromise cooling efficiency. The fiberboard gaskets are layered and hardened to withstand heat and fluid exposure common in marine engines.

• One brass/stainless thermostat with a precision valve
• Housing sleeve to secure the thermostat in place during installation
• Four gaskets (one housing gasket plus three layered thermostat gaskets) rated for oil and heat resistance

Which MerCruiser engines and part numbers does this kit fit?

This kit is designed for GM-based MerCruiser V6 and V8 engines spanning 4.3L to 8.2L produced between 1987 and 2016. It is intended as a direct-fit replacement for multiple OE and aftermarket part numbers, simplifying cross-referencing when shopping or repairing. Always verify the engine model and year before purchasing to ensure fitment.

• Compatible with MerCruiser V6 & V8: 4.3L, 5.0L, 5.7L, 7.4L, 8.2L
• Service replacement numbers include 807252Q5, 807252T8, 806922, and related OEM codes
• Fits model years 1987 through 2016—check engine casting and housing shape for confirmation

How difficult is installation and what should I prepare?

Installation is straightforward for anyone familiar with basic marine engine maintenance. The thermostat drops into the housing, the sleeve holds it in place, and the gaskets seal mating surfaces. A torque wrench, gasket scraper, and fresh coolant are typical tools and supplies required to complete the job cleanly.

• Simple placement: thermostat into housing, sleeve to secure it, then gaskets in proper sequence
• Follow torque specs and surface-cleaning steps to avoid leaks
• Refer to the included instructions for gasket orientation and tightening sequence

Who is this for: This KPALAG thermostat kit is aimed at boat owners, marine mechanics, and DIY enthusiasts who service GM-based MerCruiser V6 and V8 engines from 1987–2016. It's suitable for anyone needing a full replacement thermostat assembly with matching gaskets and a housing sleeve—especially when cross-referencing OEM numbers like 807252Q5 or 806922 is important for fit. Choose this kit if you want corrosion-resistant materials, a 160°F opening point, and a bundled gasket set to simplify a one-stop repair.