An engine misses in both the right and left positions of the magneto switch. The quickest method for locating the trouble is to...

When an engine misses in both the right and left positions of the magneto switch, it suggests that the issue is not confined to the ignition system operated by either magneto, but instead indicates a problem affecting all cylinders. The quickest and most effective way to diagnose this failure is to check for one or more cold cylinders.

Cold cylinders are indicative of a situation where one or more cylinders are not firing properly. This can happen for various reasons, such as fuel delivery issues, improper ignition timing, or other mechanical failures. By identifying cold cylinders—where the spark plugs are not firing or not receiving adequate fuel—you can quickly pinpoint whether the problem lies in the fuel system or another area impacting multiple cylinders.

This systematic approach allows for a more rapid diagnosis since checking spark plugs, inspecting magneto cables, or testing battery voltage can be time-consuming and may not directly address the root cause of the miss when multiple cylinders are involved. Thus, assessing the warmth of the cylinders is an efficient way to narrow down the issue and determine the necessary corrective action.