Chain Brake - Stihl MS 270 User Manual

4 Troubleshooting Chart
4.1 Clutch, Chain Drive, Chain Brake, Chain Tensioner
Condition
Saw chain stops under load at full
throttle
Saw chain rotates at idle speed
Loud noises
Chain sprocket wears rapidly
8
Cause
Clutch shoes badly worn
Clutch drum badly worn
Brake band stuck
QuickStop Super brake cable
broken (option)
Engine idle speed too high
Clutch springs stretched or fatigued Replace the clutch springs
Clutch spring hooks broken
Clutch springs stretched or fatigued Replace all clutch springs
Needle cage damaged
Clutch shoe retainer broken
Clutch shoes and carrier worn
Chain not properly tensioned
Wrong chain pitch
Remedy
Replace clutch shoes or install new
clutch
Install new clutch drum
Check freedom of movement
and function of brake band. If
necessary, adjust brake cable of
QuickStop Super (option)
Replace the brake cable
Readjust with idle speed screw
(counterclockwise)
Replace the clutch springs
Fit new needle cage
Fit new retainer
Install new clutch
Tension chain as specified
Fit chain of correct pitch
MS 270, MS 280