1987–1993 Yamaha Wavejammer / Waverunner 500 / 650 LX Factory Service Manual (OEM)

• Covers 1987–1991 Yamaha Wavejammer 500, 1987–1993 Waverunner 500, and 1990–1993 Waverunner 650 LX service documentation.
• Engine repair includes removal, disassembly, cylinder-head inspection, piston and crankshaft measurements, reed-valve checks, and assembly procedures.
• Carburetor sections cover diaphragm and fuel-pump service, needle-valve inspection, mixture adjustments, and differences between the 500 and 650 assemblies.
• Jet pump service covers drive shaft and impeller removal, bearing and seal replacement, and impeller-clearance adjustment using shim-selection charts.
• Electrical diagnostics include CDI-unit testing, ignition and charging-coil checks, starter-relay inspection, and starter-motor disassembly and repair.
• Steering and hull sections document steering-column removal, cable adjustment, WJ500 steering-post service, and fiberglass hull repair.

This 584-page PDF combines four service-manual sections with storage and winterization material. The service procedures are written for mechanics and use workshop measuring equipment and Yamaha service tools.

Model Identification and Engine Differences

The 500 models use the 496 cc 6K8 engine; the 650 LX uses the 633 cc 6M6. Both are water-cooled, two-cylinder, two-stroke engines with premix lubrication and reed-valve induction.

Identification pages distinguish the EU0, EW3, and FK7 hull codes and list starting primary identification and engine serial numbers. Separate specifications address differences in carburetors, ignition components, and internal engine clearances.

The 1993 WR650 section identifies top-end components that can be serviced with the engine mounted. Crankcase and crankshaft work appears separately, with engine removal specified.

Electrical Tests and System Diagrams

Wiring diagrams distinguish the WR500/WJ500 and WR650 electrical layouts. The CDI circuit diagram accompanies tester connections and resistance tables. Starter inspection extends to the armature, field coil, brushes, and commutator, with wear limits for the applicable motor.

The Engine Does Not Start troubleshooting charts separate starter-operation faults from fuel, spark, and compression problems. Further charts address irregular running, stalling, and failure to shut off.

Fuel System Diagrams identify hose connections and routing. The 1993 material adds Cooling System and Ventilation System Diagrams showing the relationships between cooling water, exhaust, bilge drainage, and compartment airflow. Exploded assembly views support component identification during disassembly.

Pump Alignment, Hull Work, and Workshop References

Engine installation sections address coupling alignment and mounting-shim placement. Intermediate-shaft chapters cover the housing, bearings, seals, and coupling. The later material adds bilge-system disassembly and inspection, plus ride-plate angle adjustment for the WR650/MJ650T.

Hull coverage extends from light scratches to puncture repairs. Later sections also document insert-nut repairs, hood hardware, and deck components; detailed FRP work is referenced to a separate Water Vehicle FRP Repair Manual.

The WJ500 steering-post section warns that an incorrect tightening sequence can loosen mounting bolts and crack the post. Earlier carburetor chapters explain how unsuitable cleaning solvents or compressed air can damage rubber parts and diaphragms.

Workshop references include maintenance schedules, compression-test specifications, tightening-torque tables, wear limits, and electrical test data. Tool listings identify equipment such as flywheel puller YB-6117 and compression gauge YU-33223-1. The 1993 tool section distinguishes U.S./Canadian tool numbers from other-market numbers.

Storage material covers cooling-system flushing, engine preservation, fuel-system preparation, battery care, and cleaning. Follow the manual’s precautions for gasoline vapors and battery isolation during service.

Included Sections and Scan Limitations

Five storage pages and four inserted overview pages bring the file to 584 pages.

Five printed pages are missing from the scan: page 4-5 in the 1987–1989 section; pages 4-9 and 5-9 in the 1990–1991 section; and pages 5-48 and 5-49 in the 1993 section. These gaps affect carburetor inspection and engine removal or disassembly coverage.