Yamaha WaveBlaster Service & Repair Manual 1993–1996 (P/N LIT-18616-01–54, LIT-18616-WB-00, LIT-18616-00-96)

• Factory model coverage: Yamaha WB700A (R-U) compilation, with explicit service data for WB700R/WB700S and the WB700AU supplement, including GA7/62E and GR7/64U identification-number groups.
• Power-unit repair: Covers reed-valve, cylinder-head, cylinder, piston, crankshaft, flywheel-magneto, engine-removal, intermediate-shaft, mounting-shim, and coupling-alignment procedures.
• Fuel and oil-injection service: Details the base single-carburetor system and WB700AU dual-carburetor update, including fuel-line and tank service, carburetor disassembly, diaphragm and needle-valve inspection, throttle/choke synchronization, oil-pump removal, hose routing, and air bleeding.
• Jet-pump and hull work: Provides jet-pump removal, impeller and drive-shaft disassembly, bearing and oil-seal installation, bilge-system service, steering/cable repair, exhaust-system work, hood/deck/seat removal, and hull-repair sections.
• Electrical diagnosis and diagrams: Includes the Electric Wiring Diagram, Pipe Routing Diagram, Oil Injection System Diagram, Cooling System Diagram, exploded assembly views, coil and starter-motor test data, plus engine-start and running-fault troubleshooting charts.
• 203-page PDF set: 1-page compilation cover (LIT-18616-WB-00), 31-page WB700AU Supplementary Service Manual (LIT-18616-01-54, First Edition, April 1996), and 171-page WB700R/WB700S Service Manual (P/N LIT-18616-00-96, First Edition, March 1993).

Factory Coverage and Variant Differences

Yamaha’s preface states that the WB700AU supplement must be used with the WB700R/WB700S service manual. Both publications are present in this file, so the WB700AU-specific changes can be read alongside the full base repair procedures instead of in isolation. The base book uses GA7 starting primary I.D. 900101, with 62E engine serials beginning 000101 and pump serials beginning 500101. The supplement changes the identifiers to GR7/64U: GR7 starts at 900101 for USA/CAN, 910101 for FRA, and 930101 for GAM/AUS, while the 64U engine and pump starts are 000101 and 500101.

The base manual already covers the 701cc engine and its single floatless carburetor. The supplement adds the WB700AU twin-carburetor layout and WB700AU-specific specifications rather than replacing the overhaul chapters. Its focused sections cover fuel and oil-injection systems, reed valves and piston-ring inspection, engine removal and coupling alignment, impeller/drive-shaft service, and revised charge- and lighting-coil checks. The base publication supplies the remaining repair depth—periodic maintenance, complete power-unit teardown and reassembly, flywheel magneto and crankshaft work, electrical-box service, starter-motor overhaul, hull and hood service, and troubleshooting.

Engine, Fuel, and Oil-Injection Repair

Fuel-system coverage goes well beyond adjustment data. The base manual documents fuel-tank removal and installation, then covers the fuel cock, filter, water separator, hoses, check valve, and carburetor with the relevant inspection and assembly procedures. The WB700AU supplement adds separate front/rear high-speed adjustments, throttle-valve and choke-valve synchronization, a fuel-pump exploded view, and oil-injection pump air bleeding. Check-valve direction, hose identification, cable-guide position, and oil-line routing are shown so the correct variant can be reassembled without relying on memory.

Inside the power unit, the factory procedures cover reed-valve inspection, cylinder-head and cylinder checks, piston and ring inspection, piston-pin and bearing work, engine removal, intermediate-shaft and housing service, flywheel-magneto removal, crankcase separation, crankshaft measurement, and final assembly. Related tables provide component-specific torques, wear limits, clearances, ignition data, and electrical test specifications.

Yamaha tool references are included for the dial gauge, compression gauge, cylinder gauge set, flywheel puller and holder, shaft holder, coupler wrench, slide hammer, driver rod, and bearing attachments. Representative numbers include YU-8036-A / 90890-06760, YB-6117 / 90890-06521, YW-38741 / 90890-06425, and YB-6156 / 90890-06634.

Jet Pump, Electrical, and Hull Sections

Jet-pump repair covers unit removal, left-hand-thread impeller removal, drive-shaft and bearing disassembly, runout and clearance inspection, oil-seal installation, bearing pressing, specified grease fills, reassembly, and bilge-system service. Steering-system inspection and adjustment continue into the hull chapter, along with steering, throttle, and choke cable replacement, exhaust water-lock work, gunwale and mat removal, engine-hood and deck service, seat disassembly, graphic replacement, insert-nut repair, and limited fiberglass hull repair. For punctured-hull details, the book refers to the separate Yamaha Water Vehicle FRP Repair Manual, an important scope limit.

Electrical diagnosis is organized around the wiring diagram and component tests. Coverage includes the starter/engine-stop switch, battery, spark plugs, thermo switch, fuse, starter relay, rectifier/regulator, ignition coil, CDI unit, pulser coil, charge coil, lighting coil, and starter motor. The starter-motor section covers removal, disassembly, brush and commutator inspection, continuity checks, reassembly, and installation. Troubleshooting charts isolate starter, fuel, ignition, compression, irregular-running, stalling, and shut-off faults.

Several repair traps are called out clearly. Steel wire must not be used to clean carburetor jets because it can enlarge the metering holes; the oil-system check-valve arrows, green-end orientation, and sub-tank “UP” mark must remain correct to protect oil delivery. Yamaha also identifies the engine-mount shim packs as coupling-alignment items and requires press installation and correct orientation for jet-pump bearings and seals, helping prevent alignment, seal, and bearing damage.

Fuel-system work involves gasoline vapors; power-unit and jet-pump service adds rotating-component hazards, and electrical work requires battery isolation. Follow the manual’s ventilation, support, and disconnection precautions, and verify unfamiliar marine power-unit repair work with a qualified Yamaha watercraft technician.