Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Armature Balance Test


1. Place armature in growler and turn power switch to GROWLER position.
2. Place contact fingers of meter test probe across adjacent commutator bars, then adjust voltage control until pointer indicates highest voltage on scale.
3. Test each commutator bar with adjacent bar. If any reading of zero volts is obtained, replace armature.