Loose Electrical Connections; Turning The Commutator - Mercury MerCruiser MCM 454 Mag MPI Service Manual

SERVICE MANUAL NUMBER 23
TEST FOR GROUND
IMPORTANT: Be sure that positive brushes and leads do not contact field frame
assembly during test, or false reading will result.
1. With continuity meter, place one lead on field connector bar and other lead on grounded
2. If meter hand moves, field coils are grounded and must be replaced.

Loose Electrical Connections

If open soldered connection of armature to commutator leads is found during inspection,
resolder with resin flux.
IMPORTANT: Never use acid flux on electrical connections.

Turning the Commutator

When inspection shows commutator roughness, clean as follows:
1. Turn down commutator in a lathe until thoroughly cleaned.
2. Recheck armature for shorts as outlined.
Index
90-861326--1 MARCH 1999
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STARTING SYSTEM
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