1999 "EE" Evinrude 70HP 4-Stroke Service Manual, P/N 787023, Page 112Get this manual
Engine Temperature Check
An OMC Temperature Gun, PIN 772018, or digital pyrometer should be used to accurately determine the engine's operating temperaturesTo achieve accurate and consistent readings, engine temperature must be gauged at the top of the thermostat pocket
INote For the following engine operating temperatures and RPM
figures to be correct, the inlet water temperature must be 70 10 (21 C)Iooo-'=-,J
Pyrometer Procedure
INote If you
get low or inaccurate readings during these tests, coat the probe location with liberal amount of Wakefield Heat Sink Compound, OMC PI 322170&
Twist and remove spark plug leads before changing propellers to avoid accidental starting of engine1Install correct test propeller and place engine in test tank2Start engine and run at 3000 RPM for at least five minutes