1990 Johnson Evinrude "ES" Cross V 88 thru 115, 150 thru 175, P/N 507874, Page 286Get this manual
Cleaning and Inspection 1Inspect the brushes; replace if one-half worn, damaged, or cracked Replace brush springs, if weak
2Clean commutator with 300 grade emery cloth If commutator surface is unevenly worn or pitted, turn on latheRemove any trace of oil or metal dust from commutator 3Check the armature on growler for shorted turns Check armature for grounding by using test light or meterInspect armature insulation for indications of overheating or damaged windings Clean off any deposits of carbon or foreign matter which may contribute to later failure of the windings
4 Check permanent magnets Magnets should strongly attract any steel or iron object held inside the frame Weak magnets will cause excessive rpm on No load Current Draw, Electric Starter test