2001–2005 Honda GL1800/GL1800A Gold Wing Factory Service Manual

This Honda Gold Wing service manual covers the 2001–2005 GL1800 and GL1800A, including standard and ABS-equipped versions. The publication page carries an August 2002 issue date.

• Engine repair: Engine removal and installation, cylinder-head and valve service, cam-chain timing, piston inspection, and crankshaft bearing selection.

• Clutch and drivetrain: Hydraulic clutch service, transmission disassembly, reverse shift mechanism inspection, and final-drive overhaul.

• PGM-FI diagnosis: MIL code retrieval, sensor and injector tests, fuel-pressure checks, and EVAP and PAIR system inspection.

• Cooling and lubrication: Radiator pressure testing, coolant bleeding, thermostat inspection, oil-pressure checks, and oil-pump disassembly.

• Suspension and steering: Separate fork-leg procedures, steering-bearing replacement, swingarm service, and electric rear spring-preload diagnosis.

• Brakes and ABS: Linked Brake System bleeding, caliper and master-cylinder service, ABS fault-code diagnosis, and modulator replacement.

• Electrical and touring systems: Starter/reverse motor tests, charging and ignition diagnosis, cruise control, audio troubleshooting, and color wiring diagrams.

Written for qualified professional technicians, the manual assumes shop safety training and access to the specified tools and test equipment.

Engine, clutch, and final-drive repair

The engine sections cover compression testing, valve-seat refacing, shim-under-bucket valve adjustment, and camshaft oil-clearance inspection. Camshaft, cylinder-head, and valve service can be performed with the engine in the frame; crankcase separation and bearing-selection tables support internal engine repair.

Clutch coverage includes master- and slave-cylinder service, disc and plate inspection, and the hydraulically assisted clutch’s operating principles. Transmission work covers gearshift linkage, mainshaft and countershaft inspection, and bearing replacement. Special-tool references include shaft holder 07JMB-MN50200 for mainshaft-bearing service.

Final-drive procedures include shim selection and gear tooth contact pattern charts. The final drive gear lock nut and starter clutch bolt have left-hand threads; the manual identifies these fasteners to help prevent thread damage from turning them the wrong way.

PGM-FI and emission-system diagnosis

PGM-FI troubleshooting connects MIL indications with sensor, injector, and ECM circuit checks. Fuel-flow testing and pressure-regulator replacement sit alongside EVAP purge-control and PAIR check-valve inspection, with vacuum-hose routing information for hose identification.

Throttle-body service is limited to the documented disassembly. Disturbing its factory-set, white-painted fasteners can upset throttle and idle-valve synchronization.

Cooling and oil-system service

Radiator and fan removal, water-pump mechanical-seal inspection, and thermostat testing are covered. The Lubrication System Diagram accompanies oil-pressure testing, relief-valve service, and oil-pump inspection, with fluid-capacity tables for service reference.

Linked brakes, ABS, and chassis

The standard brake chapter details the separate lever and pedal circuits of the Linked Brake System. GL1800A ABS coverage adds a symptom-to-system chart, code retrieval and erasure, and wheel-speed sensor checks. Faulty ABS modulators are replaced as assemblies rather than internally rebuilt.

Chassis sections distinguish left- and right-fork construction and cover the anti-dive system, steering-head bearing preload, suspension linkage, tire specifications, and rear preload-actuator circuits.

Brake and suspension work affects roadworthiness; follow the manual’s assembly precautions and final operational checks.

Reverse, cruise control, and audio troubleshooting

Connector pinouts, sensor resistance tables, and alternator tests support electrical fault tracing. The Starter System Diagram and Reverse System Diagram accompany relay, regulator, actuator, and mechanical shift checks, helping distinguish circuit faults from motor or shift-mechanism problems. Reverse shift actuator inspection, replacement, and cable adjustment are documented.

Cruise-control diagnosis covers cancel switches and actuator-cable adjustment. Audio tests address missing sound, weak reception, and automatic volume control; lighting, gauges, and power trunk locks have separate checks. Harness-routing drawings support wire and connector identification.

Valve-clearance and final-drive specification preview

The valve-clearance section specifies 0.15 ± 0.03 mm for the intake valves and 0.22 ± 0.03 mm for the exhaust valves, measured with the engine cold below 35°C. Shim-selection information accompanies these inspection values.

Final-drive backlash inspection distinguishes a standard range of 0.05–0.15 mm from a 0.30 mm service limit. Gear-contact illustrations and shim references accompany the inspection procedure.

PDF text search, bookmarks, and diagram detail

Search and wiring labels: Most service text is searchable, with chapter bookmarks for navigation. The color wiring-diagram pages are not text-searchable, and small labels on dense diagrams require zooming.

One printable English PDF contains 759 pages total: 758 service-manual pages, including the cover and nine Notes pages, and one appended reference-links page.