Winterizing Your Chainsaw: Fuel System Edition (Explained)

Winter can be a difficult time for chainsaw maintenance. Cold temperatures, snow, ice, and reduced usage can wreak havoc on your equipment if you aren’t diligent about proper storage and care. A well winterized saw will be ready to work hard when spring logging or storm cleanup rolls around. Follow this guide to keep your chainsaw’s fuel system in peak operating condition throughout the winter months.

Why Winterize Your Chainsaw?

Cold weather poses unique challenges for small engine fuel systems. As gasoline sits unused, fuel stabilizers break down over time. This allows varnishes and gums to clog passages and stick valves. Stale fuel can also separate into layers which disrupt engine performance. Then there’s the issue of ethanol attracting moisture, potentially leading to corrosion issues.

Proper winterization mitigates these problems by stabilizing fuel, removing stale gas, and preventing ice blockages. A well-preserved fuel system eliminates difficult startups, uneven running, loss of power, and other cold weather issues. Investing a small amount of time now saves hours of frustration and costly repairs later. Don’t wait until your chainsaw won’t start in the spring – winterize it today!

Step 1: Add Fuel Stabilizer

Fuel stabilizer is a must for winter chainsaw storage. This chemical additive prevents phase separation and preserves fuel integrity.

Follow fuel stabilizer directions carefully. Most recommend adding to fresh gas before the saw’s last use of the season. Run the engine for 5-10 minutes after adding stabilizer to circulate it through.

Stabilizers with antioxidants and corrosion inhibitors further protect the fuel system. Choose a reputable brand designed specifically for 2-stroke engines.

Avoid typical automotive gas additives like Heet. These absorb water but allow fuel degradation. Heet also leaves combustible deposits which can clog passages in small engines.

Step 2: Drain Old Gas

Any untreated gasoline left from summer should not be stored for winter use. Over time, untreated gas oxidizes and creates sticky resins. These damaging deposits build up in the carburetor and fuel filter. Moisture also creeps in through condensation as temperatures fluctuate.

To avoid spring startup issues, drain old gas before it deteriorates further. Use an approved fuel container to capture drained fuel. Safely dispose of old gas according to local environmental regulations.

With the fuel tank empty, now is a great time to inspect filter screens and pickup lines. Clean or replace any filters clogged with debris. Check fuel lines and primer bulbs for cracks which could leak air into the system.

Step 3: Fog the Engine

Fogging introduces a protective oil mist into the engine to prevent moisture corrosion. It coats cylinder walls and seals intake passages against condensation and rust over winter storage.

Use only fogging oils designed for 2-stroke engines. They contain anti-rust additives safe for catalytic mufflers. Read directions to determine the proper amount of oil for your engine size.

With the choke engaged, slowly pull the starter rope to draw oil into the cylinder. Rotate the engine several revolutions to spread the oil film evenly. A little fogging oil also helps lubricate the carburetor and fuel pump diaphragms.

Caution: Excessive fogging oil can cause hydraulic lock. This prevents the engine from turning over. Wipe any large drips from the spark plug and muffler outlet before storing.

Step 4: Seal Air Intakes

Sealing the air filter and carburetor air intakes prevents snow and ice from entering the engine. Use weatherproof tape designed for cold weather use. Avoid regular duct tape which can leave sticky residues.

Before applying tape, inspect intake components for any lingering dirt, sap, or debris. Carefully clean surfaces to ensure tape adheres properly.

Check the manufacturer’s manuals for guidance on taping methods. Typically, 2-3 light overlapping layers provide a good seal. Avoid excessive wrapping which makes removal difficult.

Store the chainsaw indoors where temperatures remain above freezing. This further reduces condensation risks. Frequently check seals over winter for any loosening or gaps.

Step 5: Store Properly

Proper storage positioning reduces leakage from carburetor float bowls and fuel lines. Keep the saw upright with the bar and chain facing forward. Never store tilted, upside down, or on its side.

Avoid setting the chainsaw directly on concrete. The cold mass will promote condensation inside the engine. Use a wooden platform or pallet to provide insulation against the floor.

Before storage, wipe down the saw to remove all dirt, sap, and debris. Accumulations can trap moisture against the metal. A clean machine is easier to inspect for leaks too. Apply a rust preventative spray to any nicks or dings in the paint.

Keep the saw in a dry, unheated shed or garage. Avoid temperature extremes which can accelerate fuel system degradation. Frequently check lines, filters, and seals during winter.

Common Cold Weather Fuel System Issues

Even well-winterized saws can experience problems as spring approaches. Here are solutions to some typical fuel-related starting troubles:

Issue: Chainsaw Won’t Start or Runs Rough

Check for gas varnish deposits clogging the fuel filter and carburetor jets. Soak parts in carburetor cleaner. Use compressed air to blow out passages.
The carburetor adjustments may be off after sitting. Adjust idling speed and mixture screws to factory specs.
Inspect fuel lines for cracks or holes sucking air into the system. Replace any degraded hoses.
Make sure the ignition, spark plug, and piston are all in good repair to aid startup.

Issue: Chainsaw Starts Then Stalls

Frozen ice blockages in the fuel line can restrict gas flow. Thaw lines and filters before the next use.
Poor carburetor adjustments prevent consistent running. Reset the idle speed, air/fuel mixture, and throttle cable.
Contaminated old gas causes stalling. Drain and replace with fresh stabilized fuel.
Moisture may have reached the spark plug, interrupting ignition. Dry the plug and add a water displacement cap.

Issue: Chainsaw Runs Erratically

Separated stale gas creates uneven fuel mixtures and erratic running. Drain old gas and use fresh stabilized fuel.
A sticking fuel pump check valve sends an inconsistent gas supply to the carburetor. Clean or rebuild the fuel pump.
Degraded fuel lines allow air leaks into the system. Replace cracked, stiff, or swollen hoses.
Dirty carburetor passages prevent proper fuel metering. Clean jets and emulsion tubes with carburetor cleaner.

Issue: Chainsaw Loses Power

A partially clogged spark arrestor screen restricts exhaust flow. Remove and clean the spark arrestor.
Check the air filter and pre-filter – clogged elements reduce engine power. Replace or wash reusable foam filters.
Fuel filter screen could be partially blocked. Remove the fuel filter and clean thoroughly.
The chain brake may be partially engaged, reducing chain speed. Check the brake band and linkage for adjustments.

Step-by-Step Fuel System Winterization

Use this handy checklist to winterize your chainsaw fuel supply and intake system:

Add fuel stabilizer to fresh gas in the proper ratio.
Run the saw for 5-10 minutes to circulate stabilizer.
Drain old untreated gas from the fuel tank and supply containers.
Clean or replace fuel filters, lines, and primer bulbs if needed.
Fog the engine cylinder through the spark plug hole.
Seal air intake openings with approved tape products.
Wipe down the chainsaw body and bar to remove debris.
Store upright in a dry location away from temperature extremes.
Check seals periodically and restart the saw every 4-6 weeks.
In spring, replace fuel filters, inspect lines, and adjust carburetor.

Preventative Measures

The best defense is a good offense when battling winter fuel system problems. Here are proactive steps you can take:

Use fuel stabilizer at each fill-up for stored gas. This gives constant protection.
Install an in-line fuel filter to catch contaminants before they reach the carburetor.
Upgrade fuel lines to premium polymers resistant to ethanol and weathering.
Add a fuel cap vent to relieve pressure and prevent gas seepage past seals.
Use ethanol-free gasoline or canned pre-mix fuel to avoid phase separation.
Clean the air filter, spark plug, and muffler regularly to maintain engine efficiency.
Inspect the carburetor yearly and rebuild if needed to keep saws running smoothly.

Conclusion

With proper winterization and preventative care, your trusty chainsaw will be ready to work when you need it most. Store saws upright, protected from the elements in a cool, dry place. Stabilize the fuel, seal intakes, and fog the engine. Address any lingering fuel system issues now