The MS 290 Stihl Farm Boss is a professional-grade chainsaw known for its durability and power, ideal for demanding farm and ranch work. This repair manual covers comprehensive maintenance, troubleshooting, and repair procedures for the engine, fuel system, ignition, chain drive, and safety features. Below are key sections for safety, specifications, maintenance schedules, troubleshooting, and step-by-step repair instructions.
Key components: Powerful 56.5cc engine, STIHL Quickstop® inertia chain brake, Ematic™ lubrication system, side-access chain tensioner, and anti-vibration system.
| Feature | Description |
|---|---|
| Engine Displacement | 56.5 cc |
| Power Output | 3.4 bhp (2.5 kW) |
| Guide Bar Lengths | 16" to 20" (standard) |
| Fuel Tank Capacity | 16.9 fl. oz. (500 ml) |
| Oil Tank Capacity | 8.5 fl. oz. (250 ml) |
| Weight (powerhead) | 12.8 lbs (5.8 kg) |
| Ignition System | Electronic, capacitor discharge (CDI) |
| Chain Brake | STIHL Quickstop® inertia activated |
| Lubrication System | STIHL Ematic™ with adjustable flow |
| Anti-Vibration System | Standard |
Always wear proper PPE: safety glasses, hearing protection, gloves, chainsaw chaps, and sturdy boots.
WARNING! Failure to follow safety procedures can result in serious injury or death. Always refer to official STIHL safety manual.
Access components by removing appropriate covers and using STIHL special tools where specified.
Daily/Before Use: Check chain tension/sharpness, bar condition, fuel/oil levels, air filter, all nuts/bolts, chain brake function. Every 10 Hours: Clean air filter, check spark plug. Every 20 Hours: Clean spark arrestor screen (muffler). Every 50 Hours: Clean/replace fuel filter, check/replace spark plug. Every 100 Hours: Clean cylinder fins, check clutch/drum, replace air filter. Annually/As Needed: Replace fuel lines, impulse line, carburetor diaphragm kit.
| Symptom | Possible Cause | Corrective Action |
|---|---|---|
| Engine won't start | No spark, flooded, fuel issue | Check spark plug/wire; wait if flooded; check fuel lines/filter/carb. |
| Engine starts then dies | Clogged fuel filter, carb adjustment | Replace fuel filter; adjust L and H screws per manual. |
| Loss of power | Clogged air filter, muffler screen | Clean/replace air filter; clean spark arrestor screen. |
| Chain won't turn | Clutch worn, sprocket damaged | Inspect clutch shoes/springs; replace drive sprocket. |
| Excessive vibration | Loose components, AV mounts | Tighten all fasteners; inspect/replace anti-vibration mounts. |
| Oil not lubricating chain | Clogged oil passages, pump failure | Clean oil ports; check/replace oil pump. |
| Chain brake not engaging | Band worn, mechanism dirty | Inspect brake band; clean/lubricate linkage. |
Reset: For electronic issues, disconnect spark plug wire for 1 minute to reset ignition module.
Supports top-end rebuild, cylinder/piston inspection, crankshaft bearing replacement.
WARNING! Use a piston stop when removing flywheel nut. Do not damage crankshaft threads.
Carburetor rebuild, fuel line replacement, tank vent cleaning.
CAUTION! Use only STIHL or OEM carburetor kits. Aftermarket parts may cause poor performance.
Spark plug, ignition coil (module), flywheel key inspection.
Tip: Weak or intermittent spark often indicates a failing ignition module.
Sharpening, tensioning, bar flipping, sprocket replacement.
WARNING! Always stop engine and engage chain brake before servicing chain/bar.
Refer to official STIHL MS 290 IPL (Illustrated Parts List) for part numbers. Common replacement parts:
Ordering: Use part numbers from your specific serial number range. Visit www.stihlusa.com or authorized dealer.
STIHL Limited Warranty: 1 year for homeowner use, 90 days for commercial. Proof of purchase required. This manual is for reference; STIHL recommends repairs by authorized service dealers for complex procedures. For support, contact STIHL USA at 1-800-467-8445 or visit www.stihlusa.com. Always use genuine STIHL parts to maintain performance and warranty.