Engineered Marine Products 75-08675 Vernatherm Thermal Actuator for Johnson Evinrude Outboards

The Engineered Marine Products 75-08675 Vernatherm is a precision thermal actuator designed for Johnson and Evinrude outboard engines. This component serves as the heart of the thermostat system, consisting of brass housing with an internal chamber containing a temperature-sensitive mixture that expands at a predetermined temperature. A piston fits into the chamber sealed with a rubber diaphragm, and as the waxy mixture expands from water heating up, it pushes upward on the piston to actuate the thermostat valve.

Key Features:

• Fits Johnson/Evinrude 2-cylinder 9.9-15 HP, 3-cylinder 60-70 HP, 4-cylinder 120-140 HP, 6-cylinder 185-225 HP, and V8 275-300 HP outboard engines
• Replaces OEM part numbers: Johnson/Evinrude/OMC/BRP 394411, GLM 13190, and Sierra 18-1506
• Compatible with models from 1985-1995
• Brass construction for durability and corrosion resistance
• Precision-calibrated temperature activation

The vernatherm maintains accurate engine temperature by controlling the thermostat valve, which floats slightly open at steady speeds to increase or decrease cooling water flow as needed. This critical component ensures optimal engine performance, fuel efficiency, and prevents overheating in your Johnson or Evinrude outboard motor.