1998–2000 John Deere LT133 / LT155 / LT166 Lawn Tractor Technical Manual (P/N TM1695)

John Deere technical manual TM1695 (20Sep00) covers the 1998–2000 LT133, LT155, and LT166 lawn tractors, with separate sections for engine repair, electrical diagnosis, drivetrain service, and mower decks.

Text search and schematic navigation: The PDF has searchable text and bookmarks for sections and individual procedures. The LT166 four-position-key-switch schematic bookmark has no destination; the full diagram is on PDF page 163. Small wire codes and terminal labels on the large schematic sheets require zooming.

• Engine repair: Engine removal, cylinder-head and piston inspection, valve service, crankshaft and camshaft work, and component-specific wear limits.

• Fuel and lubrication: Carburetor disassembly and inspection, governor adjustments, fuel-flow checks, crankcase vacuum testing, and engine oil-pressure tests.

• Electrical diagnosis: Wiring diagrams, harness legends, connector views, starting-motor amperage tests, charging-system checks, and PTO/RIO interlock troubleshooting.

• Gear drive: Dana Spicer 4360 transaxle disassembly and assembly, differential inspection, shaft shimming, shift-linkage adjustment, and traction-belt service.

• Hydrostatic drive and chassis: Tuff Torq K51 diagnosis, neutral and travel-pedal adjustment, brake service, sector-and-pinion steering repair, and front-axle removal.

• Mower decks: Blade timing, timing-belt and spindle-bearing replacement, deck leveling, sheave-brake service, and cutting-quality diagnostics.

John Deere wrote this manual for experienced technicians using the specified diagnostic instruments and workshop tools.

Kohler and Vanguard Engine Repair

The LT133 uses the Kohler Command LT CV13S-21525; the LT155 uses the Command 15 QT CV15S-41562. Their hydraulic lifters require no valve-clearance adjustment. The manual covers lifter inspection and bleed-down, along with automatic compression release (ACR) and cylinder-leak testing.

LT166 coverage addresses the Briggs & Stratton Vanguard V-Twin 303777, including valve-clearance adjustment and cylinder-balance testing. Internal repair procedures extend to cylinder-bore honing, connecting-rod inspection, and crankshaft and cam-gear removal.

Engine reference data includes cylinder-head flatness limits, valve and guide dimensions, piston-ring end gaps, bearing clearances, oil capacities, and torque specifications. The Kohler tool list identifies the JDG705 valve-guide reaming tool and JT035029 cylinder leak tester.

Electrical Variants and Fault Tracing

LT133/LT155 coverage distinguishes 3-amp and 15-amp charging systems, including model- and deck-specific serial breaks for the 15-amp installation. Separate drawings address three- and four-position key switches and the Reverse Implement Option (RIO).

Cranking Circuit, Ignition & Shutoff Circuit, Charging & Shunt Circuit, and PTO with RIO Circuit schematics accompany the diagnostic charts. Numbered test-point illustrations connect each check to its normal reading and follow-up test, helping isolate switch, relay, or wiring faults before replacing components.

Gear, Hydrostatic Drive, and Chassis Service

Separate drivetrain sections detail operating principles and lubrication requirements. The gear-transaxle chapter's Transaxle Components exploded view identifies the shaft, gear, differential, and shim arrangements used during reassembly.

K51 scope: Hydrostatic diagnostics address creeping in neutral, lost drive, and noisy operation. The manual covers external adjustments, fluid-level checks, and transaxle removal/installation; it does not include a complete internal K51 overhaul procedure.

The transport section warns that operating the free-wheel valve with the engine running can damage the hydrostatic transmission. Steering and brake coverage includes front-axle service and separate procedures for the LT133 and LT155/LT166 brake assemblies.

Mower Decks and Serial Breaks

Coverage includes the 38-inch deck, 42-inch mulching deck, 46-inch deck, and 48C deck. The Mower Deck Lift Linkage drawing distinguishes older and newer linkage arrangements.

For the 42-inch deck, separate procedures address deck S/N –125000 and 125001–, including blade timing, timing-belt tensioning/replacement, and spindle-bearing work. These distinctions help match the belt hardware and spindle arrangement to the correct procedure.

The timing-belt instructions explain how excessive tension can damage the belt and incorrect guide clearance can damage the belt or blades. Cutting-quality charts also address belt slip, vibration, and uneven cutting or striping.

Follow the manual's safety precautions for rotating blades, raised equipment, and loaded belt-tension springs.

PDF Contents and Included Diagram Views

The file includes an LT166 four-position-key-switch schematic dated April 25, 2001. This 396-page, printable English PDF contains 20 additional split-page views of ten full electrical sheets, one cover page, one tractor illustration page, eight notes pages, and two otherwise blank pages—all already included in the total.