1990 Johnson Evinrude 120 thru 140, 185 thru 225, 300 HP, P/N 507875, Page 48Get this manual
Maximum Spark Advance Install all spark plugs and connect spark plug leadsRun the engine with the proper test propellerDo not run the engine with propeller or flushing adapter for this adjustment1Connect timing light to No.1 cylinder2Start the engine and allow it to reach normal operating tem peratu reo r;] 3Run the engine between 4500 and 5000 RPM Check timing
on flywheel gridThe timing pointer must align with correct mark on the flywheel gridSee chart below
Maximum Spark Advance 125WT 120, 140 V6 16 BTDC 18 BTDC 18 BTDC