2005–2006 Yamaha F250TR/LF250TR Outboard Service Manual (P/N LIT-18616-02-97)

This Yamaha service manual, publication LIT-18616-02-97, is the May 2006 revised edition for the 2005–2006 F250/LF250 outboard line, covering F250TR and LF250TR. It details maintenance, mechanical repair, and fuel-system and electrical diagnosis.

• Periodic service: Maintenance interval charts, engine oil service, thermostat and cooling-water checks, control-cable adjustment, and lubrication points.

• Powerhead repair: Power-unit removal and installation, cylinder-head and crankcase disassembly, piston and bearing inspection, and oil-pump service.

• Timing and valve train: Valve-clearance inspection and shim adjustment, timing-belt replacement, camshaft and sprocket installation, and Variable Camshaft Timing (VCT) procedures.

• Fuel system: Fuel-pressure and regulator testing, low-pressure pump checks, vapor-separator service, fuel-injector installation, and throttle-position sensor checks.

• Lower unit: Separate regular- and counter-rotation repair sections covering water pumps, propeller-shaft housings, drive shafts, gear shimming, and backlash measurement.

• Bracket and PTT: Steering and mounting-bracket service, Power Trim and Tilt gear-pump and cylinder overhaul, hydraulic-pressure testing, and bleeding procedures.

• Electrical diagnosis: Yamaha Diagnostic System (YDIS) troubleshooting, ECM and electronic-throttle circuit tests, ignition, starting and charging checks, and wiring diagrams.

Yamaha prepared this manual primarily for its dealers and trained mechanics, assuming an understanding of the mechanical and electrical principles involved.

Powerhead Inspection, Timing and VCT

Internal engine work: Cylinder-head coverage includes valve-guide replacement, valve-seat refacing, and head inspection. The cylinder-block section adds piston and cylinder measurements, crankpin and journal oil-clearance checks, bearing selection, and reassembly. Exploded views and component-specific torque specifications accompany the work, including staged cylinder-head tightening requirements.

Timing precautions: The timing-belt inspection cautions identify reverse flywheel rotation as a water-pump impeller damage risk. The VCT section distinguishes cap-removal and bolt-removal holding methods because using the wrong holding point can damage the timing assembly.

Fuel Delivery and Vapor-Separator Service

Pressure-regulator checks are paired with separate fuel-pressure references for key-on and warmed-up idle conditions. Vapor-separator exploded views identify the pump, float, filter, and regulator components, while fuel, vapor-gas, and cooling-water hose-routing views document their connections.

The fuel-pressure procedure specifies gauge YB-06766 and adapter B YB-06942. Canister and check-valve inspections extend the coverage beyond the fuel pumps and injectors.

Gearcase Setup, Mounting and Power Trim

Rotation-specific setup: Separate factory shimming equations and backlash specifications help technicians match reassembly checks to the correct gearcase. The regular- and counter-rotation sections distinguish bearing arrangements and pinion, forward-gear, reverse-gear, and propeller-shaft shim selection.

Bracket and PTT work: Steering-arm and swivel-bracket coverage extends to drive-shaft bushing and oil-pan service. PTT motor, relay, switch, and trim-sensor checks support fault isolation alongside the hydraulic procedures. Exterior and clamp-bracket dimension drawings provide mounting references.

Fuel-system and PTT service involve pressurized fluid, and bracket work requires secure motor support; follow the precautions accompanying the relevant factory procedures.

ECM Circuits and YDIS Troubleshooting

Serial-specific diagrams: ECM circuit diagrams and coupler layouts distinguish the serial groups listed above. Together with the full color wiring diagrams and connector views, they help match electrical test points to the correct harness.

System descriptions explain how ECM inputs control fuel injection, ignition timing, camshaft timing, and electronic throttle operation. Starter-motor disassembly includes armature, brush, and magnet-switch checks.

Fault isolation: Trouble-code and symptom tables connect running problems to component tests, including faults without a stored code. YDIS coverage explains Engine Monitor, Stationary Test, and ECM record-data graphs.

The diagnostic test lead alone is insufficient for complete electronic-throttle diagnosis. Those checks require the separate YDIS system and connection hardware; detailed screen and graph operation is referenced to the separate YDIS instruction manual.

A Sample of Lubrication, Clearance and Pressure Data

These references are a small selection of the service specifications provided for both covered models.

Engine oil quantity is 5.6 L without oil-filter replacement and 5.8 L with filter replacement. Cold intake valve clearance is 0.20 ± 0.03 mm, and thermostat opening temperature is 58–62 °C (136–144 °F).

The fuel-pressure reference at idle after a five-minute warm-up is 260 kPa (37.7 psi). Separate key-on references in the same procedure distinguish that running value from the initial pressure checks.

Searchable PDF, Bookmarks and Wiring Detail

Text search and diagram detail: The PDF has searchable text and embedded chapter and section bookmarks, including links to the index and wiring diagrams. Small pin numbers, connector numbers, and wire-color labels in the large wiring diagrams require zooming for comfortable reading.

The download is one printable, English-language, 386-page PDF. That total includes the original front cover, two introductory pages, four wiring-diagram and legend pages, and the rear publication page.