STIHL 026 Service Manual PDF

The STIHL 026 is a professional-grade chainsaw known for its reliability and performance. This service manual provides comprehensive information for maintenance, troubleshooting, and repair of the STIHL 026 chainsaw. It covers engine specifications, fuel system, ignition system, cutting equipment, safety procedures, and detailed step-by-step repair instructions. Below are key sections for safety, specifications, maintenance, troubleshooting, and parts information.

Safety Information

Essential safety precautions for operating and servicing the STIHL 026 chainsaw.

Symbol	Meaning	Precaution
⚠️	Warning	Risk of injury - read manual before operation
🔥	Fire Hazard	Keep away from flammable materials
⚡	Electrical Hazard	Disconnect spark plug before service
👷	Personal Protection	Wear safety glasses, gloves, hearing protection
🛑	Stop Immediately	If unusual vibration or noise occurs

WARNING! Always use genuine STIHL parts. Never operate chainsaw without proper bar and chain oil.

Specifications

• Engine Type: Single cylinder, two-stroke, air-cooled
• Displacement: 48.7 cc (2.97 cu. in.)
• Power Output: 2.4 kW (3.3 hp)
• Fuel Tank Capacity: 0.55 L (18.6 fl. oz.)
• Oil Tank Capacity: 0.26 L (8.8 fl. oz.)
• Guide Bar Lengths: 40 cm (16") to 50 cm (20")
• Chain Pitch: 3/8" PMM or .325"
• Weight (Powerhead): 5.2 kg (11.5 lbs)
• Ignition System: Electronic, breakerless
• Carburetor: Zama C1Q-S series

Maintenance Schedule

Regular maintenance intervals for optimal performance.

1. Daily: Clean air filter, check chain tension, inspect guide bar
2. Weekly: Clean cooling fins, check spark plug, clean fuel filter
3. Monthly: Clean carburetor, check fuel lines, inspect anti-vibration elements
4. Every 3 Months: Replace spark plug, clean exhaust port, check clutch
5. Every 6 Months: Replace fuel filter, clean cylinder fins, check ignition timing
6. Annually: Replace air filter, check piston rings, inspect crankshaft seals

NOTE: Service intervals may vary based on usage conditions.

Engine System

Detailed engine components and service procedures.

Component	Specification	Service Procedure
Cylinder	Aluminum with Nikasil coating	Inspect for scoring every 100 hours
Piston	Forged aluminum	Measure ring end gap: 0.25-0.35 mm
Crankshaft	Two-piece construction	Check runout: max 0.05 mm
Connecting Rod	Needle bearing	Check side clearance: 0.15-0.25 mm
Crankcase	Magnesium alloy	Seal with ThreeBond 1194

Torque Specifications: Cylinder bolts: 10 Nm, Crankcase screws: 8 Nm

Fuel System

Carburetor adjustment and fuel line maintenance.

1. Fuel Mix: 50:1 (2% oil) with STIHL HP Ultra or equivalent
2. Carburetor Adjustment: Initial settings: LA=1 turn, H=1 turn, L=1 turn
3. Fuel Filter: Replace every 50 operating hours
4. Fuel Lines: Inspect for cracks; replace if hardened
5. Fuel Tank Vent: Clean with compressed air

WARNING! Use fresh fuel mixture. Stale fuel can cause engine damage.

Ignition System

Electronic ignition components and testing.

• Spark Plug: NGK BPMR7A, gap: 0.5 mm (0.020")
• Ignition Module: Electronic, non-adjustable
• Air Gap: 0.3 mm between flywheel and coil
• Kill Switch: Test continuity: 0 ohms when pressed
• Spark Test: Should jump 6 mm gap minimum

NOTE: Always disconnect spark plug wire before servicing.

Cutting Equipment

Guide bar, chain, and sprocket maintenance.

1. Chain Sharpening: File size: 4.0 mm round file, angle: 30°
2. Guide Bar Maintenance: Clean groove weekly, flip monthly
3. Sprocket Inspection: Replace if teeth are hooked or worn
4. Chain Tension: Proper tension: chain snaps back when pulled
5. Bar Oil Flow: Adjust oiler for adequate lubrication

CAUTION! Always stop engine before adjusting chain tension.

Troubleshooting

Problem	Possible Cause	Solution
Engine won't start	No spark, flooded, fuel issue	Check spark, dry plug, clean carburetor
Engine runs poorly	Dirty air filter, carb adjustment	Clean filter, adjust H and L screws
Chain won't turn	Clutch worn, sprocket damaged	Inspect clutch springs, replace sprocket
Excessive vibration	AV mounts worn, unbalanced parts	Replace AV buffers, check crankshaft
Overheating	Dirty fins, lean mixture	Clean cooling fins, enrich mixture
Oil not flowing	Clogged oiler, bad pump	Clean oil passages, replace pump

Parts List & Diagrams

Key replacement parts for STIHL 026 chainsaw.

Part Number	Description	Quantity
1125 141 1600	Cylinder Complete	1
1125 030 2001	Piston Assembly	1
1125 007 1000	Crankshaft Assembly	1
1125 141 1603	Carburetor Kit	1
1125 007 1040	Ignition Module	1
1125 640 3200	Clutch Assembly	1
1125 007 1801	Fuel Tank Assembly	1
1125 141 1605	Air Filter Kit	1

NOTE: Always verify part numbers with your local STIHL dealer.

Torque Specifications

Critical torque values for reassembly.

• Cylinder Nuts: 10 Nm (88 in-lbs)
• Crankcase Screws: 8 Nm (71 in-lbs)
• Clutch Nut: 40 Nm (30 ft-lbs)
• Flywheel Nut: 35 Nm (26 ft-lbs)
• Spark Plug: 25 Nm (18 ft-lbs)
• Guide Bar Nuts: 9 Nm (80 in-lbs)
• Muffler Screws: 8 Nm (71 in-lbs)
• Carburetor Screws: 2 Nm (18 in-lbs)

IMPORTANT: Use a calibrated torque wrench for accurate tightening.

Warranty & Support

STIHL 026 warranty information and technical support contacts.

Warranty Period: 12 months from date of purchase for commercial use, 24 months for private use.

Warranty Conditions: Covers defects in materials and workmanship. Does not cover normal wear, misuse, or improper maintenance.

Technical Support: Contact authorized STIHL dealers for service assistance.

Manual Updates: Check www.stihl.com for latest service information.

Safety Recalls: Register your product at STIHL website for recall notifications.

CAUTION: Unauthorized repairs may void warranty. Use only genuine STIHL parts.