2-Cycle Engines and the Gas Crisis

This is bad 2-Cycle Gas. Notice the water at the bottom of the jar? That was pulled out of the air by the ethanol in the gas. Make sure your containers are airtight! 

We written blogs, we’ve made videos but the number of 2 cycle trimmers and chainsaws coming into to our shop with bad gas is still increasing. Close to 2/3 of the issues that have come to our shop this year have been gas or fuel related. In this post, we’re going to outline the symptoms of a gas related problems the causes and some preventative measures you can take to keep your 2 cycle trimmers, chainsaws and blowers safe in the middle of a “gas crisis”.

Common Symptoms of Bad Gas:

  • The engine won’t start.
  • The primer bulb isn’t working.
  • There is a bad smell in the gas tank.
  • The engine isn’t revving up all the way.
  • There is excessive smoke, especially white smoke from the exhaust.

Common Causes of Bad Gas Problems:

Ethanol debris in the carburetor: This is white stuff left after ethanol dissolves out of the fuel that is sitting in your carburetor. This is caused by leaving your gas sitting in your Chainsaw or Trimmer for too long.

Fuel line and/or Primer Bulb are brittle: This is caused by the ethanol extracting the moisture from the rubber fuel line and primer bulb found in most 2 cycle chainsaws or trimmers. This is also a result of excessive exposure to high ethanol gas. 

Gas isn’t igniting/burning correctly: A lot of times gas can still reach the plug but if the mixture of fuel isn’t correct, it wont light. Meaning your machine won’t start. Or if the gas is igniting but not burning correctly you’ll have a lot of smoke, limited power and possibly a bad smell coming out of your exhaust. This can be caused by water in your fuel or the incorrect fuel in your machine.

The Fix for bad gas in your 2-cycle machine:

Often times all of these issues can be fixed by replacing your carburetor and fuel line, draining your fuel and replacing your bad gas with ethanol free 2cycle mixed gas. These repairs can cost around $40-$60 with labor, which is no small fee, however, many times this time of year 2 cycle engine repair shops can be backed up meaning you can be without your trimmer or chainsaw for weeks. Preventative measures can save you time and trouble!

Preventative Measures for 2-Cycle bad gas problems:

Purchase Ethanol Free Gas: fuel pumps can be hard to find, but if you find one, try to purchase all your 2-Cycle Mix gas ethanol free.

Have different Gas cans for your fuel: These can be differentiated by size or color but make sure that everyone who might be using the machine knows which can is filled with 2 cycle mixed gas and that your chainsaw or trimmer should only be filled from that can.

Make sure your Gas containers are secure: Make sure that the gas caps on your trimmers, chainsaws, and other 2-cycle equipment are airtight without leaks. Furthermore make sure that the gas caps on your gasoline storage containers are airtight. Ethanol will also draw water from the air, which will settle in your can or in your tank. This is why it is so important to make sure your can is airtight and your vent is closed.

Drain your gas tanks: If you’re leaving for a couple weeks or simply not using your machine. It’s a good idea to drain your fuel. It’s also a good idea to keep some Stihl Moto Mix alcohol free gas mixture around to run through your fuel system to make sure you have all the bad gas out.

Use Stihl Moto Mix: If you’re not using your equipment very much we recommend using Stihl’s pre mixed 2-cycle gas. While this run about $7.99 a quart, it can last in your tank without causing problems for up to 2 years. This stuff is the real deal but they ask a real price for it. For many of you who only use a couple quarts a year, the money you spend on Stihl Moto Mix will be well worth the cost of repair or not having your chainsaw or trimmer.

At the end of the day the gas that you put into your machine is going to effect its performance and its life, it doesn’t matter which make or model you have. More importantly, it’s going to effect your wallet a lot more to make repairs or replace trimmers and chainsaws than to take these steps to prevent bad fuel damage.