Re: Coughing After Warming Up

Posted by TxGoat On 2024/6/22 8:00:20

The float level may be too low. When the engine is cold, the automatic choke should be engaged. That could mask a low float level condition. If that's the case, and as the engine warms up and the choke opens, it could get too lean, especially under load. If it only backfires and lurches at the moment you open the throttle, it could be a problem with the accelerator pump. I would also try removing the fuel filter and see if that helps. A number of fuel delivery issues can get worse as the engine warms up. Add on fuel filters can cause problems.
(The adjustment screws primarily affect engine idle, and if the engine runs OK at at idle, they are probably OK)
Under some conditions, carburetors can form condensation or even frost internally, and that can disrupt engine operation. That problem usually occurs in cool damp weather, and it usually disappears after the engine is fully warmed up.
An inoperative manifold heat valve can contribute to carburetor "icing".