1998 Yamaha E48T / C55T Outboard Motor Factory Service Manual (P/N 696-28197-Z4-11)

• Official Yamaha E48T/C55T factory service manual — 321-page PDF, P/N 696-28197-Z4-11, cover literature code LIT-18616-01-28, first edition September 1994.
• Exact model coverage identifies E48C/E48MH, E55C, 55BM, 55BE/C55ER, 55BEM, and 55BET/C55TR, with starting serial blocks and configuration tables.
• Engine and fuel sections cover scheduled checks, carburetor and fuel-pump service, power-unit removal, internal inspection and reassembly, plus recoil-starter repair for manual-start versions.
• Lower-unit repair includes water-pump and gear-train disassembly, bearing and seal work, shim selection, backlash checks, leakage testing, and installation.
• Bracket coverage distinguishes mechanical tilt, hydro tilt, and 55BET/C55TR power trim and tilt, including hydraulic filling, bleeding, pressure testing, and motor service.
• Electrical diagnosis is supported by model-specific wiring diagrams, 703-7P/703-10P remote-control schematics, CDI, charging, starting, and PTT tests, plus symptom-based troubleshooting flowcharts.

Match the Manual to the Outboard

The cover identifies the publication as E48T/C55T, while Yamaha’s internal model tables break the coverage down into E48C, E55C, 55BM, 55BE, 55BEM, and 55BET. For USA and Canada, the manual also identifies E48MH, C55ER, and C55TR. E48C, E55C, and 55BM are manual-start models; 55BE, 55BEM, and 55BET use electric starting. Control arrangements split between tiller-handle and remote-control versions.

Tilt equipment is also model-specific: mechanical tilt on E48C, hydro tilt on E55C, 55BM, 55BE, and 55BEM, and power trim and tilt on 55BET. These are premix, two-stroke inline twins with dual carburetors, reed-valve induction, CDI ignition, and mechanical timing advance.

Fitment is keyed to the approved model number and starting serial block. E48C/E48MH is listed under model code 670 with S 010831-up and L 377728-up. Model code 663 covers E55C S 272904-up; 55BM S 252001-up; 55BE/C55ER S 004803-up and L 329002-up; 55BEM L 502490-up; and 55BET/C55TR L 721947-up. Match the identification plate, model code, S/L designation, and starting serial before selecting repair procedures.

Engine, Fuel, and Scheduled Service

The periodic inspection chapter includes predelivery inspection, control operation, fuel-line and gear-oil checks, cooling-water inspection, compression testing, idle-speed adjustment, ignition-timing checks, neutral-opening control adjustment, propeller and reverse-lock inspection, and trim-system checks where fitted.

Fuel-system coverage follows the tank, primer, filter, pump, and carburetors through removal, inspection, reassembly, and installation. Carburetor work addresses the float and needle, main and pilot circuits, air jets, pilot screw, choke parts, and the electric choke solenoid used on applicable 55BE and 55BET versions.

Power-unit repair includes removal from the boat and service of the intake and magneto components, cylinder head and thermostat, exhaust cover, crankcase, crankshaft, pistons, connecting rods, bearings, reed valves, and cooling-control components. Inspection limits, assembly data, timing checks, and final adjustments are placed alongside the related procedures. Manual-start versions receive a separate recoil-starter teardown, inspection, reassembly, and installation section.

Lower Unit, Bracket, and Trim Systems

The lower-unit chapter covers the propeller, water pump, drive shaft and pinion, forward and reverse gears, clutch dog, shift cam, propeller shaft, and bearing housing. It includes separate shim-selection charts, bearing and seal references, forward and reverse backlash measurement, shift checks, leakage testing, and installation.

Bracket-unit repair extends through the upper casing, bottom cowling, mount dampers, exhaust guide, water tube, steering and swivel hardware, reverse lock, clamp bracket, trim sender, hydro-tilt parts, and steering handle. The 55BET/C55TR section adds a construction diagram and repair coverage for the power trim and tilt valves, pistons, cylinders, motor, reservoir, hydraulic filling and bleeding, and pressure testing.

Electrical Diagrams, Fault Finding, and Factory Tools

Electrical content is arranged by model rather than reduced to one generic circuit. The manual provides electrical-component layouts; separate E48C/E55C, 55BM, 55BE, 55BEM, and 55BET wiring diagrams; a 703-7P remote-control box schematic for 55BE/C55ER; a 703-10P schematic for 55BET/C55TR; a starter-motor exploded view; and a 55BET power trim and tilt construction diagram. Troubleshooting flowcharts isolate no-start, stalling, rough-idle, power-loss, misfire, gear-shifting, and no-charge complaints.

Test coverage addresses spark and CDI operation, ignition and charge coils, stop and neutral switches, rectifier, choke solenoid, starter circuits, PTT circuits, trim sender, switches, and harness continuity. The specification chapters supply torque tables, dimension drawings, capacities, lubrication data, clearances, wear limits, electrical test values, shim and backlash data, and hydraulic test specifications.

Representative Yamaha tool listings include compression gauge YU-33223/90890-06751, flywheel magneto holder YB-6139/90890-06522, flywheel magneto puller YB-6117/90890-06521, backlash indicator gauge YB-06265/90890-06706, and CDI tester YU-91022-B.

Workshop Notes and Safety

The repair notes flag model-specific traps. During power-unit removal, using a steel or hard bar as a lever can damage the bottom cowling. In the 55BET/C55TR trim section, the gear-pump unit is identified as factory-adjusted and not intended for disassembly; replacement is handled as a complete unit.

Fuel-system, ignition, starter, lower-unit, and power-trim repair can involve gasoline, ignition voltage, battery current, rotating components, suspended engine weight, and hydraulic pressure. Follow Yamaha’s safety procedures and use trained marine service support for work beyond your experience.