Chrysler 20 and 30 HP Outboard Motors Service Manual OB 3435, Page 108Get this manual
Testing ArmatureIf inspection does not reveal the cause of failuretest the armature for shortsgrounds and balance Follow the test equipment manufacturer's procedure or use the following: 1Armature Short Test jaws and turn power APlace armature in switch to GROWLER position BHold steel band parallel with and touching armature core Slow ly rotate armature in growler jawsIf steel blade vibrates at any area of the corearea is shorted and armature must be replaced Figure 8 BTouch one test lead to armature core, touch other lead to each commutator bar one at time Observe the test lightif it glows on any bar, the armature is grounded and must be replaced
Ground test can also be done with an ohmmeterAttach one lead to core on shaftother lead to commutator sectionsMeter should show infinity or very high resistance 3Armature Balance TestAPlace armature in growler jaws and turn power switch to GROWLER position Figure 10BPlace contact fi ngers of meter test cable across adjacent commutator bars at side of commutatorCAdjust voltage control until the needle is at highest reading on scaleDTest each commutator bar with the next bar until all bars have been checked zero reading indicates an open circuit in the particular pair of bars