Stihl 170 Manual

The Stihl 170 is a lightweight, easy-to-handle chainsaw designed for homeowners and occasional users. It features a powerful gasoline engine with STIHL anti-vibration system, QuickStop® inertia chain brake, Ematic™ lubrication system, and side-access chain tensioner. Below are key sections for safety, features, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Engine, guide bar, saw chain, chain brake, throttle trigger, master control lever, fuel tank, oil tank.

Feature	Description
Engine	STIHL 2-stroke engine with electronic ignition
Anti-Vibration System	Reduces vibration for user comfort
QuickStop® Inertia Chain Brake	Stops chain in kickback situations
Ematic™ Lubrication System	Efficient chain oil delivery
Side-Access Chain Tensioner	Easy chain adjustment without tools
Master Control Lever	Combines choke, throttle lock, stop switch
Fuel Tank Capacity	Approx. 0.5 US pt (0.24 L)
Oil Tank Capacity	Approx. 0.26 US pt (0.125 L)
Guide Bar Length Options	14" or 16" (35 cm or 40 cm)
Weight (without cutting attachment)	Approx. 9.9 lbs (4.5 kg)

Safety Information

Read all instructions before operation. Wear protective gear.

1. Personal Protective Equipment: Wear safety glasses, hearing protection, gloves, chainsaw chaps, and sturdy boots.
2. Work Area Safety: Clear area of obstacles; ensure secure footing; keep bystanders away.
3. Kickback Prevention: Hold saw firmly; do not cut with tip; maintain chain sharpness.
4. Chain Brake: Test before each use; understand activation method.

WARNING! Chainsaws are dangerous; improper use can cause serious injury or death. Never operate when fatigued or under influence.

Assembly & Preparation

Unpack and inspect contents. Assemble guide bar and chain.

1. Attach guide bar: Place bar on studs, align chain, fit sprocket cover, tighten nuts.
2. Tension chain: Use side-access wheel; chain should snap back when pulled from bar.
3. Fill fuel: Use STIHL MotoMix® or mix 50:1 with 89+ octane gasoline and STIHL HP Ultra oil.
4. Fill chain oil: Use STIHL chain oil or equivalent; check for leaks.

CAUTION! Fuel is flammable; fill in well-ventilated area away from ignition sources.

Specifications

• Engine Displacement: 30.1 cc.
• Power Output: 1.5 kW (2.0 bhp).
• Fuel/Oil Ratio: 50:1 (STIHL HP Ultra).
• Idle Speed: 2,800 rpm.
• Max Engine Speed: 13,000 rpm.
• Sound Pressure Level: 103 dB(A).
• Vibration Level (front/rear handle): 4.5/3.5 m/s².
• Chain Pitch: 3/8" PMM3.
• Chain Gauge: 0.050" (1.3 mm).
• Drive Links: Varies by bar length.

Controls and Components

Right Side: Throttle trigger, throttle lockout, master control lever (choke/run/stop), rear handle. Left Side: Chain brake lever, hand guard, side-access chain tensioner. Front: Muffler, guide bar, chain catcher. Rear: Fuel cap, oil cap.

Master Control Lever Positions: STOP (0) – engine off; RUN (I) – normal operation; START (II) – choke for cold start.

Chain Brake: Engage manually by pushing hand guard forward; disengage by pulling back toward rear handle.

Starting & Stopping

Starting (Cold Engine):

1. Press decompression valve (if equipped).
2. Set master control to START (II).
3. Pump primer bulb 5+ times (if equipped).
4. Place on ground, hold rear handle with right foot, pull starter handle until engine fires.
5. Move master control to RUN (I), pull starter to start.
6. Blip throttle to disengage fast idle.

Starting (Warm Engine): Master control in RUN (I); no choke.

Stopping: Release throttle; move master control to STOP (0).

Operation Guidelines

Basic Cutting:

1. Hold saw firmly: Left hand on front handle, right on rear handle.
2. Start cut at full throttle; let chain do the work.
3. For felling: Plan escape path; use notch and backcut techniques.
4. For limbing/bucking: Support log; avoid contact with ground.

Tip: Maintain sharp chain; check chain tension frequently during first tank.

Maintenance Schedule

Daily/Before Use: Check chain tension, sharpness, brake function, fuel/oil levels. Weekly: Clean air filter, check spark plug, clean saw exterior. Monthly: Clean spark arrestor screen, check bar for wear, clean oil tank breather. As Needed: Replace fuel filter, clean carburetor, replace worn parts.

WARNING! Disconnect spark plug wire before performing maintenance.

Chain Sharpening

Use round file matching chain pitch (typically 5/32" or 4.0 mm).

1. Secure bar; identify cutters.
2. File at 30° angle; maintain file level.
3. File each cutter equally; check depth gauges with gauge tool.
4. File depth gauges to 0.025" (0.65 mm) below cutter top.

CAUTION! Wear gloves; file in direction away from body.

Storage

Long-term storage (over 30 days):

1. Drain fuel tank and run engine until it stops.
2. Remove chain, clean, and soak in oil.
3. Clean entire saw; store in dry place.
4. Cover bar and chain to prevent rust.

CAUTION! Never store with fuel in tank; fuel can degrade and damage engine.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	No spark/fuel/flooded	Check spark plug; fresh fuel; move master control to RUN and pull with throttle open.
Engine runs poorly	Dirty air filter/clogged fuel filter	Clean/replace air filter; replace fuel filter.
Chain doesn't turn	Brake engaged/loose chain/clutch	Disengage brake; tension chain; check clutch springs.
Chain throws oil	Over-oiling/incorrect oil	Check oiler setting; use correct viscosity oil.
Excessive vibration	Loose parts/damaged chain	Tighten mounting nuts; inspect chain for damage.

Service: For repairs, contact authorized STIHL servicing dealer.

Support: 1-800-467-8445; www.stihlusa.com