1993 Johnson Evinrude "ET" 90 degrees CV Service Manual, P/N 508285, Page 125Get this manual
Thermomelt Stik Procedure 1Install correct test propeller and place engine in test tank
i and remove all spark plug leads
"'" To avoid accidental starting of engine while servicing, twist
2Start engine and run at 3000 RPM for at least five minutes
r4J 3Reduce engine speed and run engine at 900 RPM for five
4At 900 RPM, the 1250 (52 C) marks should remain liquid and glossyThe 1630 (730 C) marks should remain dull and chalky
minutesMark both cylinder heads with 1250 (52 C) and 1630 (730 C) Thermomelt Stik