Husqvarna 50 / 50 Special / 51 / 55 Chainsaw Service Manual (P/N 531 03 00-76)

• Covers 1970s–1980s Husqvarna 50, 50 Special, 51, and 55 chainsaws, including detailed engine, fuel, and drivetrain configuration data
• Official publication part number 531 03 00-76
• Contains 58 pages of technical procedures including centrifugal clutch maintenance, ignition timing, and crankshaft seal replacement
• Provides the definitive assembly and identification data essential for accurately maintaining these vintage professional-grade saws

Document Coverage and Content

This factory publication breaks down the mechanical requirements for the classic Husqvarna 50, 50 Special, 51, and 55 series. You get a direct look at the ignition systems, recoil starters, and fuel delivery components specific to each variant. The chapters lay out exact inspection criteria rather than just general overviews. It zeroes in on crucial torque values for crankshaft and cylinder assemblies. Mechanics will find the exact internal wear limits for clutch shoes and brake bands, plus the required baseline settings for Walbro WA and WT carburetors.

Maintenance and Technical Data Preview

The reference material lists engine displacement ranges from 49 cc to 53 cc, paired with a standardized 2500 rpm idle speed. In the ignition section, flywheel retaining nut torque is specified at 25–30 Nm (18.4–22.1 ft.lbs.). It also covers intake manifold and carburetor linkage alignments, ensuring consistent fast-idle operation on the 51 and 55 models.

These specifications help you safely verify the 12500 rpm no-load free speed limit. Detailed wear limits for the 0.80 mm brake band are fully documented. Keep in mind that the specs discussed here serve as an informational overview. Proper shop safety protocol dictates relying directly on the complete OEM manual when turning wrenches on the bench.