McCulloch 1635 Chainsaw Manual

The McCulloch 1635 is a gas-powered chainsaw designed for general-purpose cutting, limbing, and pruning. It features a 35cc 2-stroke engine, automatic oiler, chain brake, anti-vibration system, and a 16-inch Oregon bar and chain. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

1. Features at a Glance 2. Safety Information 3. Assembly & First-Time Setup 4. Specifications 5. Controls and Components 6. Fuel & Oil Mixing 7. Starting & Operating Procedures 8. Chain Maintenance 9. Cleaning & Storage 10. Warranty Information 11. Troubleshooting

Features at a Glance

Key components: 35cc 2-stroke engine, 16-inch Oregon bar and chain, automatic chain oiler, inertia-activated chain brake, anti-vibration system, tool-free chain tensioning, and primer bulb.

Feature	Description
Engine Displacement	35cc 2-stroke air-cooled engine
Bar Length	16 inches (Oregon)
Chain Type	Oregon 91VXL (or equivalent)
Chain Brake	Inertia-activated for kickback protection
Automatic Oiler	Lubricates chain during operation
Anti-Vibration System	Reduces user fatigue
Fuel Tank Capacity	Approx. 10.1 fl oz (300 ml)
Oil Tank Capacity	Approx. 6.8 fl oz (200 ml)
Ignition System	Electronic ignition (CDI)
Weight (dry)	Approx. 10.1 lbs (4.6 kg)

Safety Information

Read all instructions before use. Always wear protective gear.

Personal Protective Equipment (PPE): Always wear safety glasses, hearing protection, gloves, chainsaw chaps, and steel-toed boots.
Kickback Zone: Avoid contact with the upper quarter of the bar tip.
Chain Brake: Test before each use by pulling forward on the hand guard.
Clear Work Area: Ensure no bystanders, pets, or obstacles within 15 feet.
Fuel Safety: Refuel outdoors, away from ignition sources. Allow engine to cool.

WARNING! Kickback can cause severe injury or death. Always grip saw firmly with both hands. Never operate above shoulder height or on a ladder.

Assembly & First-Time Setup

Unpack and inspect all parts. Assemble on a clean, flat surface.

Attach the Bar and Chain: Loosen bar nuts. Place chain over sprocket, aligning drive links with bar groove. Position bar onto studs. Ensure cutting edges face forward on top of bar. Tighten nuts finger-tight.
Tension the Chain: Use tool-free tensioning screw to adjust until chain snaps back when pulled from bar. Tighten bar nuts securely.
Fill Oil Tank: Use McCulloch chain oil or equivalent. Fill to marked level.
Fuel Mix: Prepare 50:1 gas/oil mixture (see Section 6). Fill fuel tank.
Final Check: Ensure all fasteners are tight. Chain moves freely. Brake functions.

CAUTION! Do not start the saw until assembly is complete and you have read the safety section.

Specifications

Model: McCulloch 1635
Engine Type: 2-stroke, single cylinder, air-cooled
Displacement: 35 cc
Power Output: 1.8 kW (2.4 hp)
Fuel/Oil Ratio: 50:1 (Unleaded gasoline to 2-stroke oil)
Bar Length: 16 inches (40 cm)
Chain Pitch/Gauge: 3/8" LP / .050"
Sound Power Level: 112 dB(A)
Vibration Level: Front Handle: 4.5 m/s², Rear Handle: 5.5 m/s²
Warranty: 2-year consumer warranty

Controls and Components

Familiarize yourself with all controls before starting.

Main Components: Front Handle with Chain Brake Hand Guard, Rear Handle with Throttle Trigger, Throttle Lockout, Stop Switch, Choke Control, Primer Bulb, Decompression Valve (if equipped), Chain Tensioning Screw, Side Access Panel.

Operation: Throttle Lockout must be depressed before throttle trigger can be squeezed. Stop switch stops engine. Choke enriches fuel mixture for cold starts. Primer bulb fills carburetor with fuel.

Fuel & Oil Mixing

Use fresh unleaded gasoline (min. 89 octane) and high-quality 2-stroke engine oil (ISO-L-EGD, JASO FD).

Mix Ratio: 50:1. For 1 US gallon of gas, add 2.6 fl oz of oil.
Mixing: Add oil to an approved fuel can, then add gasoline. Shake thoroughly.
Storage: Use fuel within 30 days. Do not mix more than you will use in that time.
Chain Oil: Use only dedicated chain oil for optimal bar and chain life.

WARNING! Never use automotive motor oil, dirty oil, or old gasoline. Never run engine on straight gasoline.

Starting & Operating Procedures

Cold Start:

Place saw on firm, flat ground. Clear area.
Engage chain brake by pushing hand guard forward.
Move choke lever to FULL CHOKE position.
Press primer bulb 5-6 times until fuel is visible.
Pull starter rope briskly 3-4 times until engine 'pops'.
Move choke lever to HALF CHOKE position.
Pull starter rope again until engine starts.
Allow to run for 10 seconds, then move choke to RUN. Squeeze throttle to disengage fast idle.
Disengage chain brake by pulling hand guard back toward you.

Warm Start: Use HALF CHOKE position only. Do not prime.

Cutting: Use full throttle when cutting. Let chain do the work; do not force. Plan your cut and escape path.

Chain Maintenance

A sharp, properly tensioned chain is critical for safety and performance.

Tensioning: Chain should be snug against bar but pull freely by hand. Re-tension when cold and after first few minutes of use.
Sharpening: Use a round file and guide matching chain pitch (5/32" for 3/8" LP). File each cutter at 30° angle. Maintain equal length on all cutters.
Depth Gauges: File down depth gauges (rakers) with a flat file and gauge to maintain proper height (0.025").
Lubrication: Check oil flow by running saw at speed near a light surface (like a stump). A line of oil should appear.

CAUTION! Always wear heavy gloves when handling the chain. Ensure saw is off and cool.

Cleaning & Storage

After Each Use: Clean saw of dirt, sawdust, and resin. Wipe down with a dry cloth. Check air filter.

Long-Term Storage:

Drain all fuel from tank and carburetor by running engine until it stops.
Remove spark plug, add 1 tsp of 2-stroke oil into cylinder. Pull starter rope slowly to coat interior. Reinstall plug.
Remove chain, clean in solvent, dry, and soak in oil. Store separately.
Clean entire saw. Store in a dry, cool place, covered.

CAUTION! Never store with fuel in the tank for more than 30 days. Fuel degrades and can damage carburetor.

Warranty Information

McCulloch Power Products provides a 2-year consumer warranty for the 1635 chainsaw from date of purchase against defects in material and workmanship under normal use. Proof of purchase is required. Warranty does not cover wear items (chain, bar, spark plug, air filter), damage from misuse, neglect, improper fuel, or unauthorized repair. For warranty service, contact an authorized McCulloch service center. For support, visit www.mcculloch.com or contact customer service at 1-800-521-6164.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine will not start	No fuel, flooded, spark plug faulty, choke position wrong	Check fuel. Wait if flooded. Check/replace spark plug. Follow correct starting procedure.
Engine starts then dies	Clogged fuel filter, dirty air filter, carburetor adjustment	Replace fuel filter. Clean air filter. May require carburetor service.
Chain does not turn	Chain brake engaged, clutch worn, sprocket damaged	Disengage brake. Inspect clutch and sprocket for wear. Replace if necessary.
Chain throws oil but does not cut	Dull chain, chain on backwards, depth gauges too high	Sharpen chain. Ensure chain direction is correct. File depth gauges.
Excessive vibration	Loose components, unbalanced chain, damaged anti-vibration mounts	Tighten all fasteners. Balance chain by sharpening evenly. Check mounts.
Chain comes off bar	Loose bar nuts, worn bar rails, improper tension	Tighten bar nuts. Inspect bar for wear ("rail hook"). Replace bar if worn. Properly tension chain.

Service: For repairs beyond basic maintenance, take your McCulloch 1635 to an authorized service dealer.

Support: 1-800-521-6164; www.mcculloch.com