STIHL BG 56, BG 56 C, BG 66, BG 66 C, BG 86, BG 86 C OEM Service Manual

• Covers 2008 STIHL BG 56, BG 66, BG 66 C, BG 86, BG 86 C, SH 56, and SH 86 leaf blower and vacuum units including engine, ignition, and fuel system diagnostics.
• Official STIHL service publication (2008–01 revision, P/N 0455 296 0123) providing the standardized reference for these specific engine and blower housing configurations.
• Contains detailed exploded-view assembly diagrams, precise bolt torque specifications, and electrical troubleshooting flow charts.
• Integrates highly detailed OEM spare parts lists, precise carburetor breakdowns, and exact part numbers.
• Details the ErgoStart mechanism, anti-vibration system, rewind starter, tank vent, and ignition module.

Engine and Fuel System Documentation

When diagnosing a two-stroke blower or vacuum, having the exact factory specs saves hours on the bench. This service manual provides specialized documentation for removal and installation procedures covering the engine assembly, piston, cylinder, and crankshaft. To avoid an expensive trip to the repair shop, DIYers and mechanics get step-by-step instructions for advanced maintenance tasks like replacing crankshaft oil seals without splitting the engine block, servicing a fatigued rewind spring, and performing a complete carburetor rebuild. Technicians get access to the factory-specified leakage test procedures—requiring a 0.5 bar vacuum or pressure setting—to confidently verify seal and gasket integrity. The fuel system section breaks down carburetor service, detailing the metering diaphragm replacement, inlet needle inspection, and tank vent testing. Fault isolation is further supported by specific visual aids, including carburetor basic setting views, special servicing tool drawings, component routing views, and tightening torque tables alongside the standard assembly diagrams.

Technical Specification Preview

Fastener torque is critical on these units. The manual lists specific tightening values for all plastic and metal components, including the 3.5 Nm torque requirement for M5 screws used on the filter housing and carburetor flange. It also catalogs engine power ratings across the series, from the 0.60 kW BG 66 up to the 0.8 kW BG 86, along with the precise 0.5 mm spark plug electrode gap and 0.15–0.30 mm ignition module air gap.

When executing a repair on these specific models, a common pitfall is failing to align the piston ring gap perfectly with the fixing pin in the piston groove before sliding the cylinder over it, which instantly snaps the new ring. Another frequent trap involves the Plastoform (polymer) screws securing the casings; turning them counterclockwise by hand until they drop into their original threads before tightening is absolutely necessary to prevent cutting a new thread path and permanently stripping the plastic housing.

Working on power equipment involves inherent physical risks. Always follow basic workshop safety protocols and verify your tools are properly calibrated before applying these specifications, or rely on a certified technician if you lack the necessary experience. Delivered as a 178-page PDF, this complete reference gives you the exact factory data to handle full rebuilds directly at your workbench, preventing unnecessary parts-swapping and streamlining your workflow.