Stihl MS180C Service Manual

The Stihl MS180C is a lightweight, easy-to-handle chainsaw featuring a 2.0 HP engine, STIHL Quickstop® inertia chain brake, Ematic™ lubrication system, and STIHL Easy2Start™. This service manual provides essential information for maintenance, troubleshooting, and repair. Below are key sections covering safety, specifications, maintenance procedures, fuel system, ignition system, cutting equipment, and troubleshooting.

1. Features at a Glance 2. Safety Information 3. Specifications 4. Maintenance Schedule 5. Fuel System Service 6. Ignition System 7. Cutting Equipment 8. Carburetor Adjustment 9. Troubleshooting 10. Parts Diagram 11. Warranty & Support

Features at a Glance

Key components: Engine, Fuel Tank, Oil Tank, Chain Brake Handle, Throttle Trigger, Master Control Lever, Decompression Valve, Muffler, Chain Sprocket, Guide Bar.

Feature	Description
Engine Power	2.0 HP (1.5 kW) gasoline engine
Engine Displacement	31.8 cc
Fuel Tank Capacity	250 ml (8.5 fl. oz.)
Oil Tank Capacity	145 ml (4.9 fl. oz.)
Guide Bar Lengths	12" to 16" (30 cm to 40 cm)
Chain Pitch	3/8" PMM3
Ignition System	Electronic, breakerless
Starting System	STIHL Easy2Start™
Chain Brake	STIHL Quickstop® inertia activated
Lubrication System	STIHL Ematic™

Safety Information

Always wear protective equipment: safety glasses, hearing protection, gloves, chainsaw chaps, and sturdy boots.

Read the operator's manual before use.
Inspect the chainsaw before each use for damage or loose parts.
Ensure the chain brake is functioning correctly.
Use the correct fuel mixture (50:1 STIHL MotoMix® or gasoline with STIHL HP Ultra oil).
Operate in a well-ventilated area.

WARNING! Risk of kickback. Always hold the saw firmly with both hands. Do not operate with one hand.

Specifications

Model: STIHL MS 180 C
Powerhead Weight: 3.9 kg (8.6 lbs)
Engine Type: Single-cylinder, two-stroke
Idle Speed: 2,800 RPM
Maximum Power Speed: 12,500 RPM
Spark Plug: Bosch WSR 6 F or equivalent
Fuel/Oil Ratio: 50:1 (High-quality two-stroke oil)
Sound Pressure Level: 104 dB(A)
Vibration Level: 4.5 m/s² (front/handle)

Maintenance Schedule

Access components by removing appropriate covers and screws. Always disconnect the spark plug boot before servicing.

Daily/Before Use: Check chain tension, sharpness, and lubrication. Inspect for loose nuts/bolts. Clean air intake and cooling fins.

Every 10 Hours: Clean spark arrestor screen in muffler. Check fuel filter.

Every 20 Hours: Clean or replace air filter. Check spark plug gap (0.5 mm / 0.020").

Every 50 Hours: Clean carburetor. Replace fuel filter. Check anti-vibration elements.

Fuel System Service

Fuel Tank, Cap, Filter, and Lines.

Empty fuel tank before storage or service.
Replace fuel filter: Remove tank cap and filter using a hooked wire.
Inspect fuel lines for cracks or leaks; replace if necessary.
Ensure tank vent is clear.

Tip: Use only fresh, clean fuel. Stale fuel is a common cause of starting and running problems.

Ignition System

Spark Plug, Ignition Module, Stop Switch, and Wiring.

Spark Plug: Remove, clean, check gap (0.5 mm), and electrode condition. Replace if worn.
Ignition Module: Check for spark by grounding plug against cylinder. No spark indicates faulty module or wiring.
Stop Switch: Test continuity; switch should be open when off, closed when on.
Wiring: Inspect for breaks or poor connections, especially at the spark plug boot.

WARNING! Always disconnect the spark plug boot before performing any service to prevent accidental starting.

Cutting Equipment

Guide Bar, Saw Chain, Sprocket, and Chain Tensioner.

Guide Bar: Clean bar groove and oil holes. Check for wear, especially uneven rail wear. Flip bar regularly.
Saw Chain: Sharpen with correct file size (4.0 mm round file). Maintain correct depth gauge setting.
Sprocket: Inspect for wear (spur or rim). Replace if teeth are hooked or worn.
Chain Tension: Adjust so chain snaps back when pulled from the bar. It should not sag from the bottom rail.
Lubrication: Ensure oiler port is clear and oil flow is adequate.

CAUTION! A dull or damaged chain increases kickback risk and reduces efficiency. Always use proper personal protective equipment (PPE) when handling the chain.

Carburetor Adjustment

Factory settings are typically sufficient. Adjustment may be needed for altitude or temperature changes.

Adjustment Screws: L (Low Speed), H (High Speed), LA (Idle Speed).

Start and warm up engine for 5 minutes.
Set idle speed (LA) so chain does not move and engine runs smoothly.
Adjust L screw for best acceleration from idle without hesitation.
Adjust H screw for maximum RPM (do not exceed factory max of 12,500 RPM).
Re-check idle speed after H and L adjustments.

Note: Limit caps may be present on H and L screws. For major adjustments, consult a STIHL servicing dealer.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine will not start	No spark, stale fuel, flooded engine, clogged air filter	Check spark plug and ignition. Use fresh fuel. Clear flood. Clean/replace air filter.
Engine starts then dies	Clogged fuel filter, tank vent blocked, carburetor issues	Replace fuel filter. Clear tank vent. Clean carburetor.
Engine lacks power	Dirty air filter, clogged spark arrestor, improper carb adjustment	Clean air filter and spark arrestor. Check carburetor settings.
Chain does not turn	Clutch worn, sprocket damaged, chain brake engaged	Inspect clutch and sprocket. Disengage chain brake.
Excessive vibration	Loose parts, unbalanced cutting equipment, worn anti-vibration mounts	Tighten all fasteners. Balance/replace chain/bar. Check mounts.
Poor chain lubrication	Empty oil tank, clogged oiler, wrong oil viscosity	Fill tank. Clean oil passages. Use STIHL chain oil.

Reset: For electronic issues (Easy2Start™), disconnect battery/spark plug for 1 minute.

Parts Diagram

Refer to official STIHL MS180C parts catalog (Illustrated Parts List - IPL) for exploded views and part numbers. Common replacement parts include: Air Filter (1140 140 1605), Fuel Filter (1140 120 1000), Spark Plug (WSR 6 F), Saw Chain (63 PMM3-XX), Guide Bar (3003 000 3901 - 16").

Ordering: Always use genuine STIHL parts for optimal performance and safety.

Warranty & Support

STIHL Limited Warranty: Covers defects in materials and workmanship for a specified period from date of retail purchase. Proof of purchase required. This manual is for reference only. For complex repairs, contact an authorized STIHL servicing dealer.

Support: Visit www.stihlusa.com or contact STIHL customer service at 1-800-467-8445. For dealer locations, use the dealer locator on the website.