Lawn Mower has Blue Smoke Coming From Exhaust

The infamous blue smoke coming from the exhaust is a sign of burning oil. You can also verify this by removing the spark plug. You will see a shiny black or gooey appearance on the electrode side.

Now you may have simply overfilled the engine with oil so that is the first place to start. Remove the dipstick, wipe it off and then re-insert. Pull it out and then check the level. On Asian brand engines, you do not need to screw the dipstick into the case, simply dip it in and put it back out.

If the oil level is fine, then something internal may be causing the problem. You could have a blown head gasket, a bad breather valve, your piston rings are worn or the oil seal for your intake valve is bad.

These are items that would be best diagnosed by a lawn mower engine mechanic as they have the proper tools and information to do these tests. You can find a lawn mower shop near you by visiting our Locations page. Let them know the symptoms of your lawn mower engine problems and give them as much information as you can to assist with the proper diagnosis.

What Kind of Gas Should I Put in My Lawn Mower?

Your lawn mower is usually has a 4-cycle engine on it. Some older models had a 2-cycle engine but there are not many of those left so we won’t worry about them.

A 4-cycle engine is designed to work on unleaded gasoline. There are normally 3 or 4 different octane levels of gasoline available. 85, 87, 90 and 93 are very common throughout the country. A lot of people are under the misconception that if they buy 93 octane, their engine will run better when actually the opposite will occur. A higher octane fuel is designed for a higher compression engine. Most lawn mower engines are on the lower scale of compression.

Find the lowest octane rating such as 85 and that will work fine. You could also use non-ethanol fuel to help prevent your carburetor from experiencing problems. Ethanol has been a terrible additive for gasoline engines and especially carburetor engines. Ethanol is alcohol and it attracts moisture and this adds water to your fuel. Water is never good to have in fuel.

Do not put E-85 in your lawn mower gas tank or any other alternative fuels. They will destroy your engine over time. So if you just stick with regular old pump gas, your lawn mower will run like it should.

My Lawn Mower Dies and Will Not Restart

This is a fairly common problem and it seems to get worse when it gets hot outside. After a while the lawn mower will restart and then you can mow for a while and then the same thing happens over again.

The most likely culprit here is that the ignition system is heating up and then breaking down inside. When it breaks down, it will cause the ignition coil to stop producing spark and thus the engine dies.

When your engine does die, test for spark by installing an inline spark tester and then cranking the engine. If you do not see any spark, you can assume that your ignition system is at fault. Further testing will need to be performed to narrow down the issue. You will need to know if it is the engine or the machine kill system. You can isolate this by disconnecting the kill system and then checking for spark.

If you need technical assistance with your lawn mower that dies, visit our Locations page to find a shop near you. Professional lawn mower repair companies are available to help.

My Lawn Mower Leaks Oil Out of the Exhaust

If your lawn mower suddenly developed a problem with oil leaking out of the exhaust, it could be a simple fix or a more complex one.

The simple fix could be that you simply overfilled it with oil. Check the oil level and see if that is the case. If the oil level is too full, drain some oil and check it again.

If the oil level is fine, then a component has failed in the engine. A series of tests will need to be completed to determine what the problem is. Many people do not have the tools to accomplish these invasive tests so it would be recommended that a lawn mower engine repair specialist perform them.

You can check our Locations page to see if there is a lawn mower shop near you.

If your lawn mower leaks oil out of the exhaust, it would be recommended that you do not use it until the problem has been corrected. Raw gasoline could be leaking out of the exhaust as well and it could potentially catch fire. This fire could total your lawn mower and catch other things on fire as well.