husqvarna lawn mower parts manual yth 18542

The Husqvarna YTH 18542 is a riding lawn mower featuring a 18.5 HP Briggs & Stratton engine, 42-inch cutting deck, hydrostatic transmission, and a durable steel frame. This parts manual provides detailed diagrams, part numbers, and ordering information for maintenance, repair, and replacement of components. Below are key sections covering safety, identification, engine parts, deck assembly, drive system, controls, and troubleshooting.

1. Features at a Glance 2. Model Identification 3. Safety Parts & Labels 4. Engine Components 5. Cutting Deck Assembly 6. Drive & Transmission 7. Controls & Electrical 8. Frame & Body 9. Maintenance Schedule 10. Parts Ordering 11. Troubleshooting

Features at a Glance

Key components: 18.5 HP Briggs & Stratton engine, 42-inch stamped steel cutting deck, Hydrostatic transmission, 6-speed forward/1-reverse gear drive, Electric PTO clutch, Mulching/ bagging/ side-discharge capability.

Feature	Description
Engine	18.5 HP Briggs & Stratton, single-cylinder, OHV
Cutting Width	42 inches (106 cm)
Transmission	Hydrostatic, infinite forward/reverse speeds
Deck Material	Stamped steel, anti-scalp rollers
Blades	3 high-lift blades, standard mulching
Fuel Capacity	2.5 gallons (9.5 liters)
Seat	High-back, adjustable
Drive System	Rear-wheel drive, differential lock
Battery	12V, 280 CCA
Weight	Approx. 500 lbs (227 kg)

Model Identification

Locate model and serial number plate on frame under seat or on rear fender.

Model: YTH 18542 (example: 96043012300).
Serial Number: 13-digit code indicating manufacture date.
Engine Model: Briggs & Stratton code on engine shroud.

NOTE: Always provide model and serial numbers when ordering parts.

Safety Parts & Labels

Safety components and warning labels must be intact and legible.

Blade Control System (PTO): Ensures blades stop when operator leaves seat.
Seat Safety Switch: Stops engine if operator rises without disengaging PTO.
Brake/Clutch Interlock: Prevents starting unless brake is engaged.
Warning Labels: On deck, engine, and frame indicating crush, burn, and cut hazards.

WARNING! Never operate mower with missing or damaged safety parts.

Engine Components

Engine Model: Briggs & Stratton 40N877 (example).
Air Filter: Dual-element, part # 492932S.
Spark Plug: Champion RC12YC, gap 0.030".
Oil Filter: Briggs & Stratton 492932S (if equipped).
Fuel Filter: In-line, part # 532139995.
Carburetor: Nikki or Walbro, adjustable jets.
Starter: Electric, 12V solenoid.
Muffler: Spark-arrestor type.

Cutting Deck Assembly

42-inch deck parts: blades, spindles, belts, pulleys, deck shell.

Blades: Part # 532404726 (standard), 532404727 (mulching). Replace when worn or damaged.

Spindles: Greaseable bearings, part # 532139894. Belts: Deck drive belt # 9540466, PTO belt # 9540467. Pulleys: Idler pulleys # 532141275. Deck Shell: Stamped steel, part # 532141276 (complete).

Drive & Transmission

Hydrostatic transmission (Tuff Torq K46), drive belt, axle, tires.

Transmission: Tuff Torq K46, fluid capacity 4.2 pts (2L).
Drive Belt: Part # 9540468 (main), 9540469 (secondary).
Axle: 1-inch diameter, sealed bearings.
Tires: Front 15x6.00-6, Rear 20x10.00-8.

Tip: Check belt tension and tire pressure regularly.

Controls & Electrical

Includes ignition switch, PTO switch, hour meter, wiring harness, fuses.

Ignition Switch: 3-position (Off/Run/Start).
PTO Switch: Electric engagement.
Hour Meter: Tracks engine hours.
Fuses: 20A blade fuse for electrical system.
Wiring Harness: Part # 532141277.
Battery: 12V, group U1, 280 CCA.

WARNING! Disconnect battery before servicing electrical parts.

Frame & Body

Steel frame, fenders, seat, steering wheel.

Frame: Welded steel, part # 532141278. Fenders: Steel, part # 532141279. Seat: High-back with suspension, part # 532141280. Steering Wheel: 12-inch diameter, part # 532141281.

Maintenance Schedule

Refer to operator's manual for full schedule. Key parts replacement intervals:

Part	Interval	Part #
Engine Oil	Every 50 hours	SAE 30/10W-30
Oil Filter	Every 100 hours	492932S
Air Filter	Every 25 hours	492932S
Spark Plug	Every 100 hours	Champion RC12YC
Blades	Every 25 hours (sharpen)	532404726
Deck Belt	Every 300 hours	9540466
Transmission Fluid	Every 500 hours	Tuff Torq fluid

Parts Ordering

Order genuine Husqvarna parts through authorized dealers or online.

Use part numbers from this manual.
Provide model and serial number.
Check availability online at www.husqvarna.com.
Contact dealer for technical support.

CAUTION! Non-genuine parts may void warranty and cause safety issues.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	Dead battery, bad spark plug, clogged fuel filter	Charge battery; replace spark plug; replace fuel filter.
Poor cutting performance	Dull blades, low deck height, worn belt	Sharpen/replace blades; adjust deck height; replace belt.
Transmission slips	Low fluid, worn belt, internal wear	Check fluid level; replace drive belt; service transmission.
Excessive vibration	Unbalanced blade, loose spindle, debris	Balance blade; tighten spindle bolts; clean deck.
PTO won't engage	Blown fuse, faulty switch, bad clutch	Replace fuse; test switch; replace PTO clutch.

Service: 1-800-487-5952; www.husqvarna.com