Need To Know Why Lawn Mower Smokes?

Usually, many homeowners consider their lawn mower smoking a red indicator. Somewhat, this should be the case. However, if this happens, there could be more than meets the eye. Subsequently, you should ask yourself the basic question: why is my lawn mower smoking?

Generally, the type of smoke should be another good pointer to help you to understand what is going on. Though a smoking lawn mower might not be a good sign, there is not much to worry about. It is only that some minor hitches should be fixed appropriately.

The possible lawn mower smoke types:

  • Blue smoke
  • White smoke.
  • Black smoke

These two types of smoke may indicate that oil is being consumed or burnt along with the fuel. Sometimes the oil may get into the crankcase or engine due to some simple reasons.

In case you have just replaced the oil in your lawn mower but the engine keeps emitting blue or white smoke, then there is one possibility- there is a spillage on the engine. Likewise, you might have caused the spillage on the engine by using the machine in a sloppy ground that is greater than 15 degrees. Furthermore, there could be another possibility that you tipped your machine on its side.

Managing the problem

Although the smoke might seem disconcerting, the good news is that it is normally harmless. The problem can be solved by applying the following approaches.

❖ Restart the mower.

❖ Give the oil spillage time to burn off.

❖ In case you like tipping your mower for maintenance or cleaning, review your manufacturer's manual. This will help to identify ways to handle the dangers of oil leaks.

An overfull oil reservoir

Overfilling the lawn mower could be another cause of the blue or white smoke. By using the dipstick found in the reservoir, you can ensure check the oil level. To do this:

i. Take the dipstick cap and clean the stick using a rag then put it back into the reservoir.

ii. Once again, remove the dipstick to and check the oil level. You should base the level on the prescribed "fill" line drawn on the stick.

iii. Should the oil level be extremely high, pour it (your manual should be your principal guide in this regard) and proceed to refill the reservoir with it.

iv. After adding about 75% of the amount prescribed in the manual, see the oil level.

v. Keep adding small amounts of oil to the level marked as the "fill" line.

Black smoke

With black smoke, your lawn mower could be having excessive fuel and insufficient air.

Generally, lawn mower has a carburetor that controls the ratio of air to gasoline mixture. Should the carburetor get insufficient air, the gasoline in the mixture will be higher thus creating a black exhaust smoke. Again, there could be a possibility that a clogged air filter or dirty is hindering a clear flow of air in the carburetor.

How then should you handle this?

• Replace the air filter then run the lawn mower about 5- 10 minutes.

• Check to find out if there is any change. If the black smoke persists, adjust the carburetor to increase the airflow.

If you are not new to this equipment, you may use the directions in the manual. However, you can seek services from a professional as well.

What can I do if my lawn mower smoke even after the above procedures?

Well, if the above recommendations fail to eliminate the white or blue smoke then you need to consider other approaches. First, it would be prudent to imagine that there is an air leak in your machine's crankshaft (the cast aluminum or cast iron case that shields the revolving parts of the engine).

Persisting white or blue smoke could also mean that some of the parts of the seal or the engine are wasted. If that is the case then you need to replace it as soon as possible to avoid more problems.

Likewise, if the black smoking still continues after replacing the air filter and adjusting the carburetor, there could a more severe mechanical problem. Needless to say, such problems need the aid of an expert.

If the warranty period for your lawn mower has not elapsed, things could be better. In this case, you will need to confirm with the manufacturer about the location of the most proximate servicing dealer.  

In fact, issues related to poor workmanship or factory defect may attract free repairs. If your lawn mower is not included under warranty, a legitimate repair shop should be done well to handle the problem too.

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