Stihl 064/066 Chainsaw 1992–1993 Service Manual (P/N 1122 064 0602)

• 191-page PDF set: 93-page English STIHL 064/066 Service Manual (copyright 1992), plus a 42-page July 2004 STIHL 064 spare-parts list and a 56-page July 2004 STIHL 066 spare-parts list.
• Model coverage: Workshop procedures apply to the 064 and 066; the parts catalogs identify 064, 064 W, 064 R, 064 RW, 066, 066 W, 066 M, 066 MR, 066 Arctic, and 066 BR configurations.
• Engine repair: Covers cylinder and piston removal and installation, piston-ring service, crankcase separation, crankshaft and bearing replacement, oil-seal replacement, and crankcase pressure and vacuum testing.
• Drive and oiling systems: Details clutch and sprocket service, chain-brake disassembly and assembly, chain-tensioner repair, bar-stud replacement, rewind-starter work, and oil-pump removal and servicing.
• Ignition and fuel diagnosis: Provides system-specific troubleshooting charts, analog and digital ignition service, carburetor leakage testing and overhaul, compensator operation, and separate carburetor-adjustment procedures for each ignition type.
• Electrical and parts support: Includes AV and Master Control repairs, heated-handle and generator test charts, a dedicated 066 wiring-harness catalog, 47 exploded-view parts plates, and a factory special-tool table.

This is dealer workshop material, not an operator's guide. STIHL states that its service manuals and technical information are intended exclusively for servicing dealers and staff, making this set best suited to experienced technicians who have the specified pullers, press tools, leak testers, and torque equipment.

Engine, ignition, and production changes

The engine chapter goes well beyond top-end repair. It shows how to expose the cylinder, match replacement pistons to cylinders, split and reseal the crankcase, remove and install the crankshaft with the dedicated service tools, fit the bearings and oil seals in the correct orientation, and verify the completed assembly for leakage. Component-specific tightening torques, engine and fuel specifications, ignition data, test pressures, and inspection dimensions are grouped in factory tables rather than scattered through the text.

The ignition material distinguishes early 064 analog magneto systems from the later governed digital system introduced at machine number X 18 761 250. It also covers the 066 digital module and its LED-assisted carburetor setting procedure. For 064 repairs, the service text marks the revised cylinder and muffler from X 18 760 750 and the later oil pump from X 20 361 348. It also separates the revised manifold hardware from X 20 742 548 and the updated clutch from X 22 377 760. The 066 catalog marks the broad component change at X 39 176 185 (01/1998), helping prevent earlier and later shrouds, tank housings, starter parts, and control components from being mixed.

Fuel, controls, and heated configurations

Fuel-system coverage includes diaphragm-pump operation, carburetor pressure testing, metering and pump diaphragm service, inlet-needle and control-lever inspection, throttle and choke shaft repair, tank venting, fuel pickup and hose work, and the clean-air compensator. The later parts data maps WJ-67 carburetors to the 066, 066 W, and 066 M, while the WJ-76 is listed for the 066 BR. Separate WJ-69 data covers USA/Canada 066 MR and 066 Arctic versions. Earlier WJ-65 installations and high-altitude jet options are identified as well.

The AV section identifies soft, normal, and hard buffer sets instead of treating every handle assembly as interchangeable. W and Arctic configurations receive their own generator, harness, switch, front-handle element, and rear-handle element coverage. The electrical chapter supplies a fault chart, connection views, and individual component test values, while the Master Control section explains the stop, run, warm-start, and choke functions before covering trigger, interlock, and switch-shaft repair.

Illustrations, tools, and repair cautions

The two parts catalogs pair exploded views with itemized part numbers for the crankcase, oil pump and clutch, ignition system and wiring harness, heated handlebar, WJ-series carburetors, and air-filter assemblies. The service-tool section identifies equipment such as carburetor/crankcase tester 1106 850 2905, vacuum pump 0000 850 3500, ignition air-gap gauge 1111 890 6400, and piston snap-ring installer 5910 890 2212.

The chain-brake section warns that driving the spring anchor pin out in the wrong direction can damage the locating bead and crankcase, impairing brake operation. In the heated-handle section, a rear element bonded with creases can interrupt heat transfer and overheat until it fails. Follow the manual's complete test setup before pressurizing the crankcase, and treat ignition checks as high-voltage work. Post-publication engineering updates are handled in separate STIHL Technical Information Bulletins, which are not included in this PDF.