Stihl 064/066 Chainsaw Service & Parts Manual Set, 1992–1993

The service manual provides the repair procedures; the illustrated parts lists show component positions and identify replacement parts. STIHL specifically recommends using illustrated parts lists during repair work.

Later carburetor and Arctic configurations appear in the parts catalogs as parts references, rather than additional variant-specific repair supplements. Post-publication engineering updates are addressed in separate STIHL Technical Information Bulletins, which are not included.

Searchable PDF and Chapter Bookmarks

Text search and electrical detail: Searchable text is available throughout the file. Embedded bookmarks cover the service chapters and link to the beginning of each parts catalog. Wiring-harness callouts and heated-handle connection labels are readable; zooming makes the smaller details easier to inspect.

One printable, 191-page PDF contains all three publications. Their contents pages and the two multilingual parts-symbol legends are included in the page counts above.

Engine Overhaul, Ignition Diagnosis, and Illustrated Parts

These selected content highlights outline the main workshop coverage. Other topics include tank-housing thread-insert repair and intake-air preheating parts.

• Engine repair: Cylinder and piston removal and installation, piston-ring service, crankcase separation, crankshaft and bearing replacement, oil seals, and pressure/vacuum testing.

• Clutch and chain brake: Clutch and sprocket service, brake disassembly and assembly, chain-tensioner repair, and bar-mounting stud replacement.

• Starter and chain lubrication: Rewind-starter repair, rope and spring replacement, oil-pump removal and servicing, pickup-body inspection, and hose replacement.

• Ignition and fuel diagnosis: Troubleshooting charts, analog and digital ignition service, carburetor leakage testing and overhaul, compensator operation, and ignition-specific adjustment procedures.

• Handles and controls: AV-buffer replacement, Master Control repair, heated-handle troubleshooting, generator service, connection views, and component test specifications.

• Parts and workshop references: Exploded assembly views, itemized part numbers, a dedicated 066 wiring-harness section, tightening-torque tables, and special-tool applications.

STIHL identifies this service material as intended exclusively for servicing dealers and staff; the procedures assume access to the specified pullers, press tools, leak testers, and torque equipment.

Engine Repair and Production Changes

Step-by-step instructions cover top-end and crankcase work, including matching replacement pistons to cylinders, installing crankshaft bearings and seals, and checking the assembled engine for leakage. Oil-seal replacement is also described without complete crankcase disassembly.

The pressure and vacuum tests address different leakage behavior: an oil seal can pass a pressure test yet leak under vacuum. This distinction supports diagnosis of air leaks associated with difficult idle adjustment and poor transition to higher throttle settings.

Ignition versions: Early 064 analog magneto systems are distinguished from governed digital ignition introduced at machine number X 18 761 250. The 066 material covers its digital module and LED-assisted carburetor adjustment.

The shared service text marks cylinder/muffler, manifold-hardware, and clutch changes. For the 064, it also identifies the revised oil pump and digital-only flywheel. The 066 catalog separates earlier components through X 39 176 185 from later arrangements, helping prevent incompatible shrouds, tank housings, starter parts, and controls from being mixed.

Carburetors, AV Buffers, and Heated Configurations

Fuel-system coverage extends to metering and pump diaphragms, inlet-needle and control-lever inspection, throttle and choke shafts, tank venting, fuel pickup, hoses, and the clean-air compensator.

Carburetor selection: The parts lists identify WJ-65 installations and later WJ-67 carburetors for the 066, 066 W, and 066 M. WJ-76 parts apply to the 066 BR; separate WJ-69 data covers USA/Canada 066 MR and 066 Arctic versions. High-altitude jet options are also listed.

The AV material distinguishes soft, normal, and hard buffer sets. The service instructions require matching buffer hardness within a replacement set.

Heating and controls: W and Arctic parts coverage distinguishes generators, harnesses, switches, and heated-handle components. The service chapter supplies a heating-system troubleshooting chart, test connections, and individual resistance values. It also explains that a failed front-handle heating element requires replacement of the handle.

Master Control coverage explains stop, run, warm-start, and choke functions before addressing the throttle trigger, interlock lever, and switch shaft.

Illustrations, Tools, and Repair Cautions

The catalogs contain 47 illustration pages across 34 lettered sections, including repeated plates beside continued parts lists. Examples include crankcase exploded views, oil-pump and clutch assemblies, the 066 wiring harness, heated handlebars, and WJ-series carburetors. The service manual adds ignition and heated-handle troubleshooting charts and carburetor-with-compensator diagrams.

The special-tool table identifies 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 incorrect spring-anchor pin removal can damage the locating bead and crankcase, impairing brake operation. A rear-handle heating element bonded with creases can interrupt heat transfer and fail from overheating.

Follow the manual’s complete test setup before pressurizing the crankcase, and treat ignition checks as high-voltage work.

Selected Ignition and Handle-Heating Test Data

For both models, the ignition specifications list a flywheel-to-module air gap of 0.2–0.3 mm and a spark-plug electrode gap of 0.5 mm.

The heated-handle test table specifies approximately 0.25 Ω across the isolated rear-handle element’s wire 3 and wire 4 connections. The generator reference is approximately 0.6 Ω between its wire 1 connection and ground, with the individual component connections disconnected for testing.