2004–2005 Kymco Grand Dink 250 Service & Repair Manual OEM

• A 220-page OEM PDF set in 20 chapter files, issued by Kwang Yang Motor Co., Ltd., Overseas Sales Department / Overseas Service Section, for the KYMCO Grand Dink 250, factory model SH50DA, with its water-cooled 249 cc OHC four-stroke engine.
• Covers engine removal and installation, cylinder-head and valve disassembly, camshaft timing, cylinder and piston inspection, crankcase separation, and crankshaft checks.
• Details drive and driven pulley, centrifugal clutch, drive-belt, and final-reduction service, including internal inspection, bearing and oil-seal replacement, reassembly, and kick-starter assembly coverage.
• Provides cooling- and fuel-system testing for the radiator, thermostat, thermosensor, fan circuit, water pump, CVK carburetor, auto bystarter, air cut-off valve, and vacuum fuel pump.
• Documents steering, wheel, hydraulic disc-brake, fork, and shock-absorber repair, with master-cylinder and caliper disassembly, brake bleeding, bearing replacement, and rear spring-preload adjustment.
• Includes the main wiring diagram, heater wiring diagram, cable and harness routing views, and charging, ignition, and starting circuit layouts, backed by symptom-based fault charts and electrical test specifications.
• Supplies section-specific torque data, capacities and approved lubricants, standard dimensions, service limits, wear and runout checks, maintenance intervals, and factory special-tool references.

The writing is concise and procedure-driven rather than instructional at a beginner level, making this manual best suited to professional technicians and experienced DIY mechanics who already understand safe engine, brake, fuel, and electrical repair practices and have access to the specified pullers, compressors, drivers, pressure testers, and meters.

Component and System Documentation

The engine chapters go well beyond routine maintenance. They cover oil-pump removal and rotor inspection, engine removal from the chassis, cylinder-head teardown, valve and guide evaluation, camshaft and rocker-arm checks, piston-ring and cylinder-bore inspection, and crankshaft bearing and runout measurement. The cylinder head and cylinder can be serviced with the engine in the frame; crankcase separation and internal water-pump service require engine removal. This distinction matters when planning bench space, lifting support, and the actual depth of a repair.

Transmission coverage follows the scooter's automatic drive from the variator through the driven pulley and clutch to the final reduction. The manual describes belt and roller inspection, clutch-shoe and outer-drum checks, driven-face disassembly, pulley-bearing replacement, clutch reassembly under spring load, and final-drive shaft, gear, bearing, and seal service. Kick-starter parts appear in the transmission assembly coverage, while the starter clutch has its own removal and inspection procedures.

Fuel-system material covers how the carburetor jets and vacuum-operated fuel pump work before moving into diagnosis and component service. Procedures include carburetor removal, vacuum- and float-chamber disassembly, jet and passage inspection, auto-bystarter testing, air cut-off and accelerator-pump diaphragm checks, float-level inspection, fuel-pump output testing, and fuel-tank and strainer removal. Cooling-system pages add radiator-cap and system pressure testing, fan and thermostatic-switch checks, thermostat and thermosensor testing, coolant-mixture tables, water-pump bearing service, and mechanical-seal replacement.

The chassis chapters address body panels and exhaust access, steering-head races, front and rear wheels, wheel bearings, dual hydraulic disc brakes, front shock absorbers, the fork, rear fork, and twin rear shocks. Brake coverage includes master-cylinder and caliper disassembly, seal and piston inspection, pad and disc limits, refilling, and air bleeding. Fuel, hot coolant, brake fluid, and spring-loaded clutch work require proper support, ventilation, protective equipment, and the correct holding or compression tools.

Technical Reference and Specification Data

Electrical diagnosis is organized around the complete vehicle wiring diagram plus charging, CDI ignition, starting, and heater circuits. Test sections cover the battery and A.C. generator, regulator/rectifier, ignition coil, pulser and exciter coils, CDI unit, starter motor and relay, handlebar switches, horn, fuel sender and display, cooling-fan switch, temperature meter, instruments, lights, throttle-position sensor, and mirror controller. The symptom charts trace hard starting, low power, engine noise, drive or clutch faults, no-spark conditions, charging failures, gauge faults, steering pull, suspension problems, and poor brake performance.

Useful visual references include the lubrication-system diagram, fuel-pump construction view, cooling-system schematic, full wiring diagram, charging and ignition circuit layouts, and exploded assembly drawings for the engine, CVT, final drive, and chassis. Factory tool callouts include the E003 flywheel puller, E021 flywheel holder, E027 clutch tools, E014 mechanical-seal and bearing drivers, F004 rear-shock compressor, and F005 steering-head bearing remover.

Two assembly cautions are especially specific to this scooter. The water-pump impeller uses a left-hand thread, so treating it like a conventional fastener can damage the impeller or shaft. At the front wheel, incorrect alignment of the speedometer-drive retaining pawl can deform it when the axle is tightened.