1996 Johnson Evinrude "ED" 9.9 thru 30 2-Cylinder Service Manual, P/N 507122, Page 137Get this manual
Thermomelt Stik Procedure 1Install correct test propeller and place engine in test tank
i pellers, twist and remove all spark plug leads
"" To avoid accidental starting of engine while changing pro-
2Start engine and run at 3000 RPM for at least five minutesf4l 3Reduce engine speed to 900 RPM and mark the cylinder head with 1250 (52 e) and 1630 (73 e) Thermomelt Stik4At 900 RPMthe 1250 (52 e) mark should remain liquid and glossyThe 1630 (73 e) mark should remain dull and chalky If the 1250 (52 e) mark does not remain liquid and glossy, troubleshoot the cooling system for causes of overcooling If the 1630 (730 e) mark becomes liquid and glossy, troubleshoot the cooling system for causes of overheatingf4l 5When the engine speed is increased to 5000 RPM, the 1630 (73 e) mark should remain dull and chalky If the mark becomes liquid and glossy, troubleshoot the cooling system for causes of overheating