Chainsaw Overheating

Black smoke, or white and blue smoke after 10 minutes suggests an engine problem behind the smoke. First, let your saw cool down, and check the air filter. The air filter feeds your carburetor with clean, ambient air. If your air filter is full of oil or sawdust, you can try spraying with compressed air or washing with soap and water. In the event your filter is too destroyed, replace the filter completely.

We know sawdust is flammable, so when it accumulates near the exhaust of the saw, it can combust and cause smoke. Clean off the cooling fins and remove wood from under the bar cover.

Running too rich over time can clog the metal screen in the exhaust. Remove and inspect the screen. Put the screen into a vise, and use a torch to heat and burn all of the carbon on the screen until it becomes ash. Use a wire brush to remove the ash, then replace.

When mixing the fuel and oil ratio, adding too much oil will result in white smoke from the exhaust. Adding more gasoline to your mixture should clear the smoke.

However, if you notice an overheating saw, try adding more oil to your fuel mix. Failure to add any oil to the fuel mix will cause destruction of the engine.

With use, the chain's teeth need to be resharpened. Dull teeth are evident in the dust produced from cutting instead of chips, and from a hot chain and bar. Grab a round file of appropriate diameter and sharpen the chain.

Overloading or running your saw continuously for too long is likely to overheat your saw's motor. Let it rest for 30 minutes, then continue.

Your carburetor needs period adjustment based on seasonal temperatures, or after so many hours of use. Smoking is an indication that your carburetor isn't getting enough fuel and too much air. This condition is dangerous for your engine because overheating can cause the piston rings to fail and self-destruct. Turn the H screw out counterclockwise while the saw is running at max throttle until the RPM drops, then turn back slightly. This will make the fuel mixture more rich.

When smoke is coming from the exhaust while the chainsaw is idling, the L screw needs adjusting. Turn the screw counterclockwise until you hear the RPM drop and smoke stop. Verify with factory specifications.

The oiler dispenses oil on the chain and bar and keeps the chain lubricated and cool. If the oil reservoir is empty, the bar and chain will become increasingly hot. Add oil, and allow the saw to cool down.

Sawdust, dirt, and other particulates can clog the filter to the oiler. Verify that the filter isn't clogged, and replace or clean if necessary.

Sawdust may also clog the oiler where it dispenses fluid. Remove the bar guide and clear any foreign materials away from the oiler orifice

It your saw is stored in a dirty place and exposed to dust and debris, the exhaust port may become clogged. This is more noticeable if you regular use the saw because the sound coming out of the exhaust will sound different.

After many cycles of sharpening and dulling, or hitting an object like a rock, it's possible the chain is too worn out to continue cutting. In this case, replace the chain. However, with normal use the chain teeth dull and rakers need adjusting.

When the raker, which alternates with teeth on a chain, is higher than the tooth tooth, it can be a source of inefficient cutting and heat buildup. To fix this, file the raker with raker gage or by eye to a lower level than the teeth.

A chain that's too tight can put undue stress on the motor and cause it to overwork. Loosen the chain slightly, and tighten the nuts.

A chain that is too loose may be slipping and cutting inefficiently, building up heat in the bar and chain. Increase the tension, and tighten the nuts.