Many problems with a John Deere riding mower can be quickly and easily repaired by cleaning or adjusting an engine part. A damaged engine part is another common cause of problems and can be corrected by replacing the part.
Some safety features of John Deere riding mowers will prevent the mower from starting. The safety switch, usually located under the seat, must be depressed, the mower blade has to be disengaged and the brake pedal has to be pressed for the mower to start. Loose or corroded electrical connections can make a riding mower difficult to start. Disconnected or loose spark plug wires can also prevent the mower from starting. Other causes of starting problems include a plugged fuel filter, an improperly adjusted choke cable and a dirty or improperly adjusted carburetor.
A common cause of poor engine performance is dirty or plugged engine parts. If the air cleaner or cooling fins are plugged the engine may run unevenly or overheat. Plugged cooling fins can also cause the engine to vapor lock. A dirty, damaged or improperly adjusted spark plug can cause the engine to idle unevenly, miss under a load, backfire or overheat. A loose electrical connection can cause the engine to run unevenly, as can a sticking choke or throttle cable.
A plugged fuel line or fuel filter can cause an engine to run unevenly, miss or vapor lock.
A loose hose connection from the fuel filter to the fuel pump or a plugged fuel tank vent can also cause vapor lock.
If the starter does not work or turn over the engine on a John Deere riding mower, the fusible link in the starting circuit or a fuse may be blown. A dead battery or corrosion on the battery terminals can cause the engine not to start. Corroded terminals or cables can also prevent the battery from charging properly. In addition, the battery will not charge if it is low on water or has a dead cell.
If the fuel is stale, dirty or the wrong type, a John Deere riding mower may be difficult to start, not start at all, or knock when running. Alcohol or ether can cause deposits of gum and varnish in fuel, especially if the mower has been stored for several weeks. Suppliers blend fuels differently, which may cause difficulty in starting the mower, and you may have to change suppliers.
An overloaded engine or low oil level can cause the engine to knock. Operating the mower at an idle or a slow speed for long periods may also cause knocking, as well as overheating. Mowing too fast for the conditions can cause the engine to lose power. If the engine stops or misses on a hill, the fuel tank may be less than half full or the operator may be rising from the seat.
If you have checked all the possible causes of a problem and the mower still does not operate correctly or if you have a problem that is not listed, contact a local John Deere dealer.