1991 Johnson/Evinrude EI Outboards 2.3 thru 8 Service Manual, Page 138Get this manual
Engine Temperature CheckAll Models The Markal Thermomelt Stik is heat-sensitive marker that melts on contact with surface of specific temperatureOne source for Thermomelt Stiks is Stevens Instrument CompanyThe Thermomelt Stik mark will appear dull and chalky when the surface marked is below the Stik's rated temperatureWhen the surface exceeds the Stik's rated temperature, the mark will appear liquid and glossyr.jl To achieve accurate and consistent readings, engine temperature must be checked on the lower port cylinder head screw for 2.3, 3.3 and on the cylinder water jacket for thru 8
r:::-=J For the following engine operating temperatures and RPM
figures to be correct, the inlet water temperature must be 700 100 (21 30 C)Thermomelt Stik Procedure
i lers to avoid accidental starting of engine
"'" Twist and remove spark plug leads before changing propel-
1Install correct test propeller and place engine in test tank