Yamaha Grizzly 660 2005 Owner's Manual (P/N LIT-11626-18-03)

• 676 pages across two PDFs for the Yamaha Grizzly 660: a YFM660FAT Owner’s Manual plus the YFM660FP Service Manual and YFM660FR/FS supplements. Workshop coverage is FP, FR, and FS, with FAT covered by the owner’s manual.
• Engine repair coverage includes removal and installation, cylinder-head and valve work, piston and cylinder inspection, crankshaft replacement, and camshaft timing.
• V-belt drive and transmission service covers primary and secondary sheave disassembly, centrifugal clutch inspection, shift forks, the reverse-drive chain, and shift linkage adjustment.
• Shaft-drive procedures address CV joints, middle gears, and the rear final drive, with shim selection and gear-backlash measurement. Front differential coverage includes gear-motor checks and installation alignment.
• MIKUNI BSR42 carburetor service includes teardown, diaphragm and needle-valve inspection, and float-height and fuel-level adjustment. Cooling-system work covers radiator-cap pressure testing, thermostat checks, and water-pump repair.
• Hydraulic brake sections cover master cylinders, calipers, pad replacement, and bleeding. Chassis procedures extend to wheel bearings, steering knuckles, tie rods, suspension arms, and the rear stabilizer.
• Electrical fault tracing covers ignition, starting, charging, cooling-fan operation, and four-wheel-drive selection, supported by circuit diagrams, switch-continuity charts, and component tests.

Included Publications and Model Coverage

The 198-page YFM660FAT Owner’s Manual, P/N LIT-11626-18-03, is the March 2004 first edition. It covers vehicle operation, preventive maintenance, and minor repairs.

The separate 478-page service PDF combines the 407-page YFM660FP Service Manual, P/N LIT-11616-15-01 (May 2001), the 53-page YFM660FR supplement, P/N LIT-11616-16-34 (June 2002), and the 18-page YFM660FS supplement, P/N LIT-11616-17-14 (April 2003). These page counts include the covers and introductory material.

The supplements update the FP base manual rather than replace it. Yamaha specifies using the FS supplement with both earlier publications. For a FAT owner, the distinction matters: FAT operating and maintenance coverage is included; a FAT-specific workshop supplement is not.

Operational Content Overview

The owner’s manual outlines the foundational control functions of the YFM660FAT. It explains the On-Command four-wheel drive system, differential gear lock engagement, override switch, and auxiliary DC power access. Pre-operation checks address fluid levels, brake inspection criteria, throttle operation, and tire pressure management.

Riding sections cover climbing, descending, crossing slopes, and managing rider weight on uneven terrain. Front and rear carrier limits, trailer pulling load, tongue weight, and total vehicle loading are distinguished rather than treated as one interchangeable capacity.

For routine upkeep, the manual describes panel removal, engine-oil and filter replacement, gear-oil changes, coolant replacement, and air-filter and spark-arrester cleaning. It also covers the V-belt cooling duct check hose and case drain plug after water exposure. Valve-clearance and select-lever safety-cable adjustments are referred to Yamaha service personnel.

Ten warning and specification labels are keyed to their vehicle locations. Identification pages show the VIN and model-label locations, while the owner-level troubleshooting charts address starting problems, poor engine performance, and overheating.

FR and FS Service Updates

The FR supplement revises cable routing and service information for the starter clutch, middle driven shaft, front differential, and wheel-hub hardware. Its chassis pages cover steering-knuckle and rear-knuckle bearings, the stabilizer, and rear suspension removal.

The FS supplement addresses the differential-lock override switch, its speedometer display behavior, revised switch-continuity checks, and the signal-system circuit. Updated carburetor, suspension, and ignition specifications accompany these changes.

Diagrams, Specifications, and Repair Planning

The service reference includes Coolant Flow Diagrams and Oil Flow Diagrams for tracing fluid paths. The Electric Starting System Circuit Diagram supports starting-interlock diagnosis; the 2WD/4WD Selecting System Circuit Diagram supports relay, switch, and actuator testing. Complete YFM660FP and YFM660FS Wiring Diagrams identify circuit components and wire colors.

Exploded assembly views accompany removal and disassembly sections. Component-specific torque tables, wear limits, clearances, fuel-tank and fluid capacities, compression-test data, and electrical test specifications support the repair procedures. Special-tool references include the secondary-sheave spring compressor YM-04134 and the FR coupling gear holding tool YM-01486.

Repair Limits and Safety

Differential service does not authorize unrestricted teardown: Yamaha identifies the factory-assembled differential unit and gear motor as non-disassembly items.

The middle-driven-shaft instructions warn that direct hydraulic-press loading can damage the shaft-end threads. The drivetrain troubleshooting section also identifies insufficient gear backlash as destructive to the gear teeth.

Brake-system repair and drivetrain reassembly require a qualified technical background; incorrect work can compromise vehicle control.