1974 Johnson 135 HP Outboard Motors Service manual, Page 119Get this manual
'-7 CLEANING, INSPECTION AND REPAIR
aInspect the brushes for wear and chipped corners; replace brush holder assembly if brushes are one- hal! worn, damaged or cracked or if brush springs are weakSpring should not take set if complete ly collapsed The circuit breaker contact points can be leaned, but use care not to spring the bi-metal strip Use of an extra fine emery loth trip cut and rolded to polish both pOints will clean and smooth them for continued long lifeCheck armature shaft ball bearing lo smooth operation and wearbWipe all components lean and dry Avoid use of solvent since may soften insulation on armature and fieldClean commutator with grade 00 sandpaperIf commutator surface is worn unevenly or pitted, turn on latheUsing suitable tool, clean grooves between commutator segments to prevent shortingRemove any trace of 01 1cCheck the armature on growler for shOrted turnsCheck armature for grounding by using test light or meterVisually Inspect in sulation fOr indications of overheating Or damaged Remove any deposits of carbon or foreign matter which may contribute to later failure of the windingsdUSing test light, check field windings for continuity between field brush lead and the respective input lead for each of the two field windings