1997 Johnson/Evinrude EU 25, 35 HP 3-Cylinder outboards Service Manual, Page 153Get this manual
3Tighten the thermostat housing and cover securely
rn onto new thermostat housing O-ring and cover Install O-ring the thermostat assemblyrn 5Install the thermostat assembly in the cylinder headTighten to 60-84 inIbs(7-9 Nm)