Yamaha Rhino 660 YXR66FAV UTV 2004–2006 Service Manual (P/N LIT-11616-19-41)

• Covers Yamaha Rhino 660 YXR660FAS, YXR660FAT, and YXR66FAV models, including standard- and special-edition FAV specifications and wiring.
• SOHC single-cylinder engine repair procedures cover removal, cylinder-head and valve-train overhaul, piston and cylinder inspection, crankcase separation, and crankshaft installation.
• V-belt automatic transmission coverage includes primary and secondary sheave disassembly, centrifugal clutch inspection, and high/low/reverse sub-transmission service.
• Shaft-drive sections detail CV-joint and universal-joint service, middle-gear shim selection, differential gear-lash adjustment, and rear final-drive rebuilds.
• Hydraulic brake work includes master-cylinder and caliper overhaul, system bleeding, and service of the rear caliper’s self-adjusting parking-brake mechanism.
• Electrical troubleshooting covers CDI ignition, starting and charging faults, On-Command 2WD/4WD selection, differential-lock controls, and carburetor-heater testing.

Manual Set and Model-Specific Updates

The set contains 521 pages across three PDFs: the 421-page YXR660FAS Service Manual (LIT-11616-17-23, July 2003), the 42-page YXR660FAT Supplementary Service Manual (LIT-11616-18-46, August 2004), and the 58-page YXR66FAV Supplementary Service Manual (LIT-11616-19-41, first edition July 2005).

Yamaha specifies using the YXR66FAV supplement with the earlier supplement and base manual; all three are included. The later supplement is not a stand-alone repair manual.

For the 2006 FAV, U.S. model codes are 5UG9, 5UGB, and 5UGF.

The FAT supplement updates carburetor and CDI specifications, V-belt transmission data, intake-duct filtration, and parking-brake adjustment. The FAV supplement revises hub fastener specifications and chassis procedures. It distinguishes standard steel wheels and bulb indicators from special-edition cast-aluminum wheels and LED/LCD instrumentation.

Engine, Fuel and Chassis Repair

The base manual spans ten core chapters, starting with baseline specifications and periodic maintenance schedules. Maintenance procedures include valve-clearance adjustment, compression testing, and ignition-timing checks. Engine overhaul coverage extends to valve-guide replacement, valve-seat refacing, camshaft and decompression checks, oil-pump inspection, and balancer installation.

Mikuni BSR42 carburetor service includes diaphragm and coasting-enricher inspection, plus float-height and fuel-level adjustment. Fuel-pump testing is covered separately. Cooling-system work covers radiator-cap pressure testing, water-pump seal replacement, and oil-cooler removal. Named Oil Flow Diagrams and Coolant Flow Diagrams trace those circuits.

Rack-and-pinion steering service includes backlash adjustment and tie-rod inspection. The double-wishbone suspension sections cover arm and ball-joint replacement, rear-knuckle and stabilizer checks, and shock-absorber inspection. Toe-in and spring-preload adjustments are also documented.

Symptom-based troubleshooting separates hard starting and poor idle from clutch slip or shaft-drive noise. Dedicated fault lists also address overheating and unstable handling.

Repair Limits and Workshop Tooling

Front differential coverage stops short of internal teardown of the factory-assembled gear unit or gear motor. Their removal, testing, and installation are covered, along with case service and adjustment.

Shaft-drive cautions warn that insufficient gear lash can destroy gear teeth. Steering notes identify a separate risk: housing damage during pinion needle-bearing removal.

Factory tool references identify the YM-04134 sheave spring compressor, YM-01467 gear-lash measurement tool, and YU-90050 crankshaft installer set. Exploded assembly views and job charts identify parts, lubrication points, replacement requirements, and fastener torques.

Electrical Diagnostics and Technical Specs

Electrical diagnosis pairs battery checks and switch-continuity tests with circuit-specific voltage and resistance measurements. References include the Electric Starting System and 2WD/4WD Selecting System circuit diagrams, plus the Signaling System (for special edition models) diagram. The latter supports coolant-warning diagnosis at the multifunction meter, including thermo-switch and diode checks.

The FAV update also adds headlight-relay testing. Model-specific wiring diagrams and Cable Routing drawings identify connector locations and harness paths.

Factory reference data includes component-specific torque tables, pressure-test specifications, fluid capacities, wear limits, clearances, and electrical test values.

Brake work, loaded sheave springs, and raised chassis components require proper training and support equipment; consult a qualified technician before attempting repairs beyond your experience.