Johnson V4 Normal operating Temp

[bang2568]

Just Curioius. What should the normal operating temperature be at idle and WOT for a Johnson 110 v4. I will be measuring Cylendar head temp.

[cousy]

At idle should be around 60 to 70 deg C and at wot should be a bit cooler.
thermostats control idle temp, at wot thermostats should be pushed of there seats by water pressure, there is no min temp for wot.

[EMDSAPMGR]

On a 140 crossflow, the thermostats open at 143. You will find that the engine will idle between 143 and 150. When on plane at WOT, the pressure relief valves open and water inflow becomes unregulated, so the temps will probably go down.