2002/2003 Johnson SN/ST 2 Stroke 3.5, 6 8 HP Outboards Service Manual, PN 5005466, Page 138Get this manual
POWERHEAD TEMPERATURE CHECKALL MODELS
TEMPERATURE CHECKAll Models
Measuring Temperature
Temperature Gun, PIN 772018, or digital pyrometer should be used to accurately determine the engine's operating temperatures
IMPORTANT: For the following engine operating temperatures and RPM figures to be correct, the inlet water temperature must be 70 10 (21 C)68 Model
1Top of cylinder block
IMPORTANT: If you get low or inaccurate readings during these tests, coat the probe location with liberal amount of Wakefield Heat Sink Compound, PIN 322170
Temperature Gun Pyrometer Test
Idle Temperature
Digital
Install correct test propeller and place outboard in test tankTemperature Gun, PIN 772018