STIHL TS 400 Repair Manual PDF

The STIHL TS 400 is a professional-grade cut-off saw designed for demanding construction and demolition work. This repair manual provides comprehensive instructions for troubleshooting, maintenance, disassembly, and reassembly of the TS 400. It covers the engine, fuel system, ignition system, cutting system, and all major components. Below are key sections for safety, specifications, maintenance procedures, troubleshooting, and parts identification.

Safety Information & Warnings

Before attempting any repair, read and understand all safety instructions. The TS 400 is a powerful tool that can cause serious injury or death if mishandled.

Technical Specifications

• Model: STIHL TS 400 Cut-Off Saw
• Engine Type: 2-stroke, single cylinder, air-cooled
• Displacement: 64.1 cm³ (3.91 cu. in.)
• Power Output: 3.0 kW (4.0 hp)
• Fuel/Oil Mix: 50:1 (STIHL HP Ultra or equivalent)
• Idle Speed: 2,800 RPM
• Max. RPM (Cutting): 9,500 RPM
• Cutting Wheel Diameter: 300 mm (12") or 350 mm (14")
• Weight (Powerhead): Approx. 9.5 kg (20.9 lbs)
• Ignition System: Electronic, STIHL CDI
• Carburetor: STIHL Zama or equivalent diaphragm carb

Tools & Workshop Requirements

Required tools for most repairs include:

1. STIHL Special Tools: Piston Stop, Flywheel Puller, Clutch Holding Tool.
2. Standard Tools: Torx & Hex key sets, socket set, torque wrench, needle-nose pliers, circlip pliers.
3. Cleaning: Parts cleaning solvent, compressed air, shop towels.
4. Measurement: Feeler gauges, spark plug gap tool, multimeter.

WARNING! Use only STIHL-approved replacement parts to ensure safety and performance.

Routine Maintenance

Regular maintenance prevents major failures.

1. Daily: Check fuel for contamination, inspect cutting wheel for damage, clean air filter.
2. Weekly: Check spark plug condition and gap (0.5 mm / 0.020"), inspect fuel lines for cracks.
3. Monthly: Clean cooling fins, check carburetor adjustment, inspect anti-vibration elements.
4. Annually: Replace fuel filter, check cylinder compression, inspect clutch drum bearing.

CAUTION! Never operate with a damaged or missing safety guard.

Fuel System Repair

Common issues: Hard starting, poor idle, loss of power.

1. Fuel Tank/Vent: Remove tank, clean interior, inspect and replace tank vent if clogged.
2. Fuel Lines: Replace all lines (supply and return) if hardened or cracked.
3. Fuel Filter: Replace in-tank filter. Ensure pickup is not restricted.
4. Carburetor Rebuild: Disassemble, clean jets and passages with solvent, replace diaphragm, gaskets, and needle valve. Re-adjust H, L, and LA screws to factory settings.

Ignition System Repair

Components: Spark plug, ignition coil (CDI module), stop switch, wiring.

1. Testing Spark: Remove plug, reconnect boot, ground plug against cylinder. Pull starter – look for strong blue spark.
2. Coil Air Gap: Set between 0.2-0.4 mm (0.008-0.016") using feeler gauge.
3. Resistance Check: Use multimeter to test primary and secondary coil windings per manual specs.
4. Switch Test: Check stop switch for continuity when pressed.

Tip: Weak or no spark often indicates a faulty coil or broken wire.

Engine & Cylinder Repair

Major engine service procedures.

1. Cylinder & Piston Inspection: Remove muffler, inspect cylinder walls for scoring. Check piston rings for free movement.
2. Piston Replacement: Use piston stop to hold crankshaft. Remove circlips, piston pin, and install new piston with arrow facing exhaust port.
3. Crankshaft Seals: Leaking seals cause air leaks. Remove clutch and flywheel, pry out old seals, press in new ones flush.
4. Decompression Valve: If equipped, test for leakage. Replace valve assembly if engine is hard to start.

WARNING! Label all parts during disassembly. Use new gaskets upon reassembly.

Cutting Attachment & Gearbox

Maintaining the drive and cutting system.

1. Gearbox Oil: Drain and refill with STIHL gear oil (approx. 100 ml). Check for metal shavings indicating wear.
2. Clutch Inspection: Worn clutch shoes will not engage properly. Replace if worn thin or cracked.
3. Shaft & Bearings: Check for smooth rotation. Replace output shaft bearings if rough or noisy.
4. Cutting Wheel Mounting: Always use correct flange and nut. Tighten nut securely in direction opposite wheel rotation.

Troubleshooting Guide

Exploded Views & Parts List

Refer to the official STIHL parts catalog for the TS 400. Key assembly diagrams include:

• Cylinder / Piston / Crankshaft Assembly
• Carburetor / Air Filter / Fuel Tank Assembly
• Ignition / Flywheel / Starter Assembly
• Clutch / Gearbox / Output Shaft Assembly
• Handle / Control / Throttle Linkage Assembly

Note: Always use the part number from the diagram when ordering replacements.

Torque Specifications

Critical fasteners must be tightened to specified values.

Service Support: For genuine parts and technical assistance, contact an authorized STIHL dealer or visit www.stihlusa.com.