Should I Buy A Used Chainsaw? Here’s why I wouldn’t…

A chainsaw is a great tool to have in the woodshed. They can be quite temperamental so choosing to buy a used one may not be the best choice.

Buying a used chainsaw is not advisable as they are hard to tune, especially if they have been dropped or cracked.

There are many different yard tools available, some will last forever if well maintained while others won’t. Chainsaws are like the diva in the woodshed. With lots of attention, they run like a dream but if not they will break your heart. 

What Are You Going To Use the Chainsaw For?

Picking the correct tool for the job is half the battle. There are many different types of chainsaws available, gas and oil (2-stroke), electric battery, electric corded. Selecting the correct chainsaw for you will depend on what job or chore you require it for.

Light cutting of timber with a light chainsaw will be sufficient but if you intend to fell trees then a larger two-stroke saw will be required.

Choosing the Correct Saw

Unlike many yard tools, a chainsaw used incorrectly can have fatal consequences. It is not a tool to be complacent about. Although there are safety features, you must be aware of your own physical capabilities. If you can’t hold a saw for any length of time then you must choose a lighter one.

Choosing a new vs a used saw has the benefits of a vendor showing you the correct procedure for use and all the safety features. That’s not to say a seller of a used saw won’t be as thorough, however, due to it being a used saw, the safety features may not work as well as they should or may be compromised altogether.

Cost of a Chainsaw

If we are considering buying a used chainsaw then the cost is going to be part of the discussion.

A new chainsaw cost will range from $100 – $600 depending on the size, brand, and power source. Gas is more expensive than electric or corded but gas-powered have more capabilities out in the field. 

The average medium/ heavy duty is going to set you back approximately $200. So why am I talking about new chainsaw prices when you’re asking should I buy a used one?

Problems with Used Chainsaws

The thing about buying a used chainsaw is ‘Why is the person selling the saw?’ As I said chainsaws are temperamental. Gas-powered saws are two-stroke engines. This means that they don’t have an internal oil reserve but the user must pre-mix the gas and oil.

The two-stroke refers to the number of strokes of the piston head – the piston moves once (first stroke) and moves the crankshaft halfway (air and fuel move down the cylinder) and then the second stroke completes the cycle (air and gas is compressed ready for combustion). So that’s all a bit technical but it’s important to understand the importance of what’s known as the Air Fuel Ratio (AFR) as if this is not correct, your chainsaw will run erratically. The ratio has to be 14.7 parts air to 1 part gas. This ratio is controlled by the carburetor. 

A chainsaw should be able to idle smoothly but if it has too much air your saw will surge (running lean) or too much gas (running rich or fat) it will splutter.

Surging Engine

A used chainsaw, being used will have some issues. AFR issues are common which in many cases, tedious carburetor tuning may fix them but very often there’s something else going on. Something that can’t be tuned out and in many cases this won’t be apparent until the saw gets up to working temperature.

The problem with a used chainsaw is, you never know the history. The nature of their work means they are outdoors and the biggest concern is – Has the saw has been dropped, or something heavy (a tree!) fallen on it. A chainsaw is a sealed unit, the outer casing is part of the engine, and it’s critical it’s airtight.

A heavily dropped saw may develop cracks in the body. So why does this make a difference? Back to our AFR. If the body (plastic) is cracked then air will be able to enter the engine. This will disrupt the AFR and you will never get your chainsaw to run sweet for you. 

Many chainsaws are sold for this reason. Watch out especially for saws with new carburetors, this indicates the seller tried to make the repair but found out the problem wasn’t the carburetor after all. A seller unfortunately may not tell you that the saw has been dropped.

Dirty Carburetor

With chainsaws, it’s all about the AFR. Dirt in the carburetor or gas filter is a common root cause of a ton of chainsaw poor performance or no-start issues. One of the most common problems is storing a chainsaw with gas in the tank. Chainsaws can’t be left with fuel in them for any length of time (more than one month), as it goes stale and causes gumming in the carburetor.

A gummed carburetor prevents proper fuel delivery and this means no matter how hard you try, you won’t get the saw to run properly by tuning the carburetor. The carb at best will need to be cleaned or at worst replaced.

But remember a used saw price must make sense, not much point in saving money on the purchase price only to make up the price of a new by adding new parts or a ton of time-wrenching.

Gumming can be avoided, by the way, using a gas stabilizer in the fuel system when storing. I covered it here in the video – “Mixing and adding gas stabilizer”.

The video shows it being added to a lawnmower but it works for all gas-powered engines but, you should know this is not a substitute for two-stroke oil and should be added last after you’ve mixed your two-stroke gas mix.

Low Compression

Gas saws as you know are two-stroke, meaning oil must be mixed with the gas. It’s this oil that prevents engine damage. It is critical therefore that the oil is at the correct ratio. Incorrect oil mix is common among light occasional saw users.

Getting the oil mix wrong can cause irreversible piston and cylinder damage. In the worst-case scenario, the engine seizes, meaning the internals fuse together.

You’ll know a seized saw as the pull starter won’t turn the engine.

But the damage can occur before the engine actually seizes. Scoring of the cylinder, rings, and piston wear results in low cylinder compression. The symptoms of same vary depending on how bad it is, typically it results in no or hard starting, idling issues, lack power, won’t idle or hold the throttle.

You’ll find the cost of repairing such a saw uneconomical.

Safety Features

The most important chainsaw safety feature is the Chain break. When a saw tip bites into the wood it can sometimes kick the saw tip upwards violently.

The chain brake is a handguard designed to make contact with the operator’s hand automatically in the event of a kickback. When the operator’s hand makes contact with the spring-loaded guard, it activates the chain brake which as its name suggests, stops the movement of the chain immediately.

Kickback is rare these days as chains and bars are designed to minimize them. That said incorrect saw use will produce kickback and you most definitely want your chain brake to work.

Chain & Bar Issues

The two most likely components to be damaged on a chainsaw are the chain and the chain bar. These are the business end of cutting and are obviously important. A lack of oil is a common root cause of a badly damaged bar and chain.

That said bar and chain are wearing items and can be easily replaced and are relatively inexpensive.

Chainsaw Oil Pump

The chain saw has an oil pump, not for the engine, it’s two-stroke. No, the oil pump is for the chain and bar. Oil is delivered to the bar and chain to help reduce friction, which in turn reduces heat and keeps bar and chain wear to a minimum. In addition, it helps maintain a sharp chain and a well-lubed chain reduces the chances of kickback.

Pumps do wear out and become clogged. Some operators use waste car engine oil in the bar oil reservoir which shortens the pump, chain, and bar life.

The problem is when the pump lets go and stops delivering oil to the bar, a few knock-on effects are common, some serious.

They are as follows:

• Increased chance of kickback
• Increased bar wear
• Increased chain wear
• Overworked engine
• Excessive heat transfer to saws plastic body
• Excessive vibration to saws body

Other Used Chainsaw Issues

Still think buying a used saw is a good idea? Here’s a collection of other issues you may need to deal with. Not all serious but all are defo a pain in the ass to repair.

• Sticking throttle
• Perished fuel lines
• Cracked carburetor intake mount
• Carburetor gasket vacuum leaks
• Worn out carburetor
• Pull cord and or pawl wear/broken
• Broken engine mounts

New is the Better Choice

A used chainsaw is not worth the cheaper price tag, unless you know and trust the seller, or are permitted to run and cut timber with the saw until hot, I’d pass on the deal. The time you will spend ‘fiddling’ with the carb to get it to run properly is just not worth it.

Unless you have a thing for bringing old yard tools back to life, I would steer clear of a used chainsaw. It will burn your time and may also be a serious safety hazard.

A used saw from a saw dealer is fine, presumably, it will be serviced, safety checked, and come with a warranty.

You may find the following posts helpful:

Chainsaw troubleshooting page

New saw won’t start

Saw won’t start after sitting

Do I need chainsaw insurance?