Troubleshooting Chart; Clutch, Chain Drive; Chain Brake; Chain Tensioner - Stihl MS 290 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
Chain does not stop immediately
when brake is activated
MS 290, MS 310, MS 390
Cause
Clutch shoes badly worn
Clutch drum badly worn
Brake band stuck
Engine idle speed too high
Clutch springs stretched or fatigued Replace the clutch springs, or
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
Insufficient chain lubrication
Chain sprocket worn
Brake spring stretched or broken
Brake band stretched / worn /
broken
Clutch drum worn
Remedy
Install new clutch
Install new clutch drum
Check freedom of movement
and function of brake band
Readjust with idle speed screw
(LA) (counterclockwise)
clutch if necessary
Replace the clutch springs
Fit new needle cage
Fit new retainer
Install new clutch
Tension chain as specified
Fit chain of correct pitch
Check chain lubrication
Install new chain sprocket
Fit new brake spring
Fit new brake band
Install new clutch drum
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