tl;dr
- Put the choke in the off position.
- Pull the start the engine.
- If the engine doesn’t start after two pulls, put the choke in the on position and pull to try to start the engine again
Normally
- when the engine has been off for a long time, e.g. after storage, you need to choke the engine by turning the choke to the on position and then pulling the rope to turn the engine on.
- when the engine has been running and you temporarily turn it off for, say, 15 minutes, then the engine is still warm and you don’t need the choke to be on to restart the engine. if you restart a warmed-up engine with the choke on, the engine won’t start because there will be too much fuel going into the engine.
More Details
- A choke control is a fuel and air mixture control system found on many carburetedengines. Engines with fuel-injection systems do not have carburetors, so they won’t have choke controls.
- Manually operated choke control systems are commonly found on outdoor power equipment.
- The manual choke control system allows the small engine equipment operator to temporarily adjust the fuel to air mixture and makes starting an engine that has not been used for a considerable length of time easier.
- The expression; “choke the engine ” refers to placing the carburetor manual choke control into the engaged (starting) position. When an engine carburetor is “choked”, the fuel to air mixture ratio becomes richer (more fuel & less air) than normal, for easier cold starting and to assist in getting the fuel flowing through the system. This control will then need to be returned to normal operating (run) position soon after the engine starts, warms up, and the fuel flows normally.
- The choke control is NOT to be used for re-starting after the engine has warmed to normal operating temperature. Choking and attempting to re-start an already warmed engine will result in too much fuel and will prevent a warm engine from re-starting. If it is suspected that the engine may still be warm enough to re-start after a short break, such as less than 15 minutes or so, try re-starting it with the choke off. A warm engine should start easily with the choke off.
- It’s recommended to first try starting an engine twice (2X) without using the choke, as it is not always necessary to restrict the air flow, and too much fuel and not enough air could actually prevent starting.
As the engine operating temperature warms and normal fuel flow is established, the choke control will need to be SLOWLY moved back to the normal operating position, as not to cause the engine to stall from too much fuel. The speed at which this control is moved back into the normal operating position will vary. On very warm days, the choke will need only to be on a few seconds. On extremely cold days, it may require more time for the engine to be sufficiently warmed before the choke can be returned to the normal operating position.
LISTEN TO THE ENGINE – As the newly started engine warms up with the CHOKE ON, it will begin to starve for air and sound like it wants to stall. This is the signal to start slowly releasing the choke. During periods of extremely cold outside temperatures, it may require a slightly more time before the choke control can be slowly moved back into the normal operating position. The rate that the engine warms up, the temperature outside, and the distance the fuel needs to be drawn from the fuel tank to the carburetor, are all factors in this relationship.