Overview

Manufacturer: STIHL. Product type: Genuine replacement O-ring, part number 9646 945 0490, designed for 7x1.5 mm seals. This small rubber ring is used in STIHL handheld power equipment to seal tight housings and fittings, supporting reliable operation of carburetion, fuel, and lubrication circuits across compatible models. The part is manufactured to STIHL OEM specifications to ensure proper fit and sealing performance under vibration and varying temperatures.

Key takeaway: correct O-ring size (7x1.5 mm) and DIN3771 specification are matched to a broad range of STIHL tools, helping restore pressure seals and reduce leaks without altering performance.

Key Features

• Part Number: 9646 945 0490
• Size & Standard: 7 mm x 1.5 mm (DIN3771-S7X1.5)
• Type of machine: Suitable for STIHL chainsaws, brushcutters and cut-off saws; commonly used across models such as MS192C and MS075, with applicability to many STIHL handheld tools.
• Installation tips: Replace during routine service, inspect seating surfaces for damage, clean grooves, and seat evenly to ensure a proper seal; use a lubricant compatible with rubber and fuels to facilitate seating if recommended by service guidelines.
• Material / Durability: Rubber seal designed to resist typical fuels, oils and cutting lubricants used in outdoor power equipment, maintaining seal integrity under vibration.

Compatibility

• Suitable machine models: STIHL chainsaws, brushcutters, and cut-off saws; documented compatibility includes MS192C and MS075 among other STIHL handheld tools.
• Additional model references: Listed as a common OEM seal across multiple STIHL platforms; guided by STIHL part documentation and cross-referenced service lists (e.g., MS 231 C-BE, MS 382 family in related parts catalogs).
• Alternative part numbers: No official alternative STIHL part numbers published for this exact O-ring; some retailers and DIN references list the same size as DIN3771-S7X1.5, which aligns with the 9646 945 0490 specification.