We interrupt this program to go back to the original topic for a moment...

Another useful trick for getting the low speed needle close to correct can be done with the glow driver. Start the engine, leave the glow driver connected and run the engine up to full speed for 10-15 seconds. Then idle back. After about 15 seconds, remove the glow driver. If the engine slows a small amount, the low speed needle is about right. If the engine slows considerably, the low speed needle is set too rich.