1998 Johnson Evinrude "EC" 90, 115 SPL Service Manual, P/N 520209, Page 130Get this manual
Thermomelt Stik Procedure 1Install correct test propeller and place engine in test tank&
To avoid accidental starting of engine while servicing, twist and remove all spark plug leads2Start engine and run at 3000 RPM for at least five minutes
rn 3Reduceboth cylinder headsrun engine at (52 C) andfor 163 engine speed and 900 RPM five minutesMark with 125 a
F (73 C) Thermomelt Stik4At 900 RPM, the 1250 (52 C) marks should remain liquid and glossyThe 1630 (73 C) marks should remain dull and chalky If the 1250 (52 C) marks do not remain liquid and glossy, troubleshoot the cooling system for causes of overcooling If the 1630 (73 C) marks become liquid and glossy, troubleshoot the cooling system for causes of overheating