Stihl MS 661 User Manual

9MS 661, MS 661 C-M
3.2 Chain Drive, Chain Brake, Chain Tensioner
Condition Cause Remedy
Chain sprocket wears rapidly Chain not properly tensioned Tension chain as specified
Wrong chain pitch Fit chain of correct pitch
Insufficient chain lubrication Check chain lubrication
Saw chain stops under full load Brake band blocked Check freedom of movement and
operation of brake band
Saw chain does not stop
immediately when brake is
activated
Chain brake spring
stretched / broken
Fit new brake spring
Brake band
stretched / worn / broken
Fit new brake band
Clutch drum worn Install new clutch drum

Stihl MS 661 Specifications

General

Displacement	91.1 cc
Chain Pitch	3/8"
Engine Power	5.4 kW
Fuel Capacity	825 ml
Chain Oil Capacity	360 ml
Guide Bar Lengths	90 cm