Dwell is the amount of time a spark plug’s points are closed, allowing current to flow through the coil and generate a spark. Dwell is measured in degrees of crankshaft rotation and is typically between 25 and 45 degrees. Checking dwell is important because it can help you identify problems with your ignition system, such as a weak coil or faulty points.
The importance of dwell cannot be overstated. A properly set dwell will ensure that your engine runs smoothly and efficiently. If the dwell is too short, the spark will be weak and the engine will misfire. If the dwell is too long, the coil will overheat and the points will burn out.
