failure mode

FM-08: FM-08 CHAIN IS LOOSE, SAGS, OR WILL NOT HOLD TENSION

FM-08 CHAIN IS LOOSE, SAGS, OR WILL NOT HOLD TENSION

Diagnostic overview

FM-08 CHAIN IS LOOSE, SAGS, OR WILL NOT HOLD TENSION

Likely Root Causes

  • New chain has stretched during break-in
  • Bar-adjust locking knob was not tightened
  • Chain tension was set incorrectly
  • Worn chain, bar groove, or tensioner parts
  • Chain was adjusted while hot

Quick Checks

  1. POST-REPAIR CHECK

Related symptoms

  • The chain hangs below the guide bar, can be pulled too far from the rail, or becomes loose again after adjustment.

    The chain hangs below the guide bar, can be pulled too 1. Remove the battery, let a hot chain cool, and check for no visible sag under the

Included in the full manual

  • root cause analysis
  • tools needed
  • step-by-step repair procedure
  • diagrams
  • exploded views
  • post-repair checks

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