Charon
|
When the engine is idling, cylinder pressures are at about the lowest they will ever be. That makes it easier for the spark to jump the plug gap. As the throttle is opened the cylinder pressures rise, and it becomes more difficult for the spark to jump the plug gap. In turn, that means the spark voltage rises. If there is a weak spot in the insulation of the plug wire, such as a chafed spot, the spark may find it easier to jump that spot instead of the plug gap. If the plug is incorrectly gapped (too wide) the spark might not make it across under high-pressures. I'd start by changing the plug, as being an easy troubleshooting job (besides, after going through the work to get at it, you are better off changing it than fooling with trying it again). While all the parts are off you have good access to look over all the other wiring. If it will idle, the valves and the other mechanicals can't be far wrong, and it is exceedingly unlikely the same problem exists with both carburetors.
|