STIHL Cover Washer - 4180 162 1000

Key Features

• Precision-cut to STIHL OEM dimensional tolerances for unmodified bolt-to-hub alignment
• Carbon steel substrate provides fatigue resistance under repeated shock-loading cycles
• Zinc-chloride conversion coating suppresses oxidation when exposed to sap, moisture, and debris
• Controlled spring-rate geometry maintains prescribed end-play across spindle and cover interfaces
• Meets ISO 7089 flatness standards to eliminate fastener preload loss

Product Details

The STIHL Cover Washer (OEM Reference 4180 162 1000) serves as a dedicated axial spacer and load spreader for motor mount brackets, sprocket housings, and chassis guard assemblies. Manufactured via cold-heading processes followed by hardness balancing, the component distributes clamping forces uniformly across mating surfaces to prevent warping of adjacent polymer or cast-aluminum structures. Surface treatments comply with commercial salt-spray testing benchmarks, ensuring longevity in abrasive forestry and landscaping applications. Installation requires removal of the retaining fastener, seating of the washer flush against the reference face, and reapplication of manufacturer-specified tightening torque. Routine inspection should occur every fifty operating hours; replacement is mandatory when inner diameters show elongation, edge chamfering exceeds tolerance limits, or plating degradation exposes base metal.

Compatibility

• CHAINS: MS 170, MS 180, MS 250, MS 270 (cross-match serial prefix 7xxxxxx through 9xxxxxx)
• BRUSHCUTTERS: FS 38, FS 48, FS 56, FS 89, FS 90
• BRANCH CUTTERS / POLE PRUNERS: HP 55, PK 10, PK 50, PK 70
• Always validate against the machine’s serial plate and official service diagram revision before procurement