There are a few things you expect to smoke: campfires, grills, and stressed-out people. You do not expect your tractor to smoke, so when billowing clouds of white or gray start emerging from its engine, it's normal to be alarmed. The first thing you should do is turn the tractor off and back away. Let it rest for a few hours to cool off completely. Then, you can get to work on figuring out why your tractor is smoking. Here's a look at some of the most common explanations.
The engine is being broken in.
If the tractor is brand new, there's a chance the smoke may just be the result of the engine being broken in. On some makes and models of tractors, the piston rings are coated with a special oil when they are manufactured. This oil needs to burn off when the tractor is first started. Typically, the kind of smoke emitted in such a case is white or bluish, and it has a chemical scent. The smoke should dissipate after you use the tractor two or three times; you don't need to be worried or do anything about it.
The air filter is dirty.
If the engine air filter is too clogged with dirt and debris, then not enough air may be reaching the combustion chamber. Thus, too much gas is reaching the chamber, and when it is burned, smoke is released. Typically, the smoke released in this situation is black and smelly. It may have an oil-like scent. If you replace the air filter, the problem should go away. You can purchase new air filters at most garden stores, though if you have a larger, less common tractor, you may need to buy from an online tractor parts retailer.
The carburetor is not adjusted or needs to be cleaned.
The carburetor is designed to spray gasoline into the combustion chamber. The amount it sprays is dependent on the choke setting. However, if the carburetor is dirty or clogged, or if it is not adjusted properly, the proper amount of fuel may not be reaching the chamber. This can lead to smoke which is often gray or black in color. (If you change the air filter and the tractor is still smoking, the carburetor is likely to blame.) Follow your owner's manual's instructions for cleaning the carburetor. If this does not work, then some of the components may need to be replaced by your local repair shop.
If you find out you need new parts, contact a business like Bub's Tractor Parts.