All this time I thought my various glow drivers were fine. They all produced a reddish glow. This new one I bought and have just charged up practically makes the plug glow white! No problems starting the stubborn engines now!

You may shorten the glow plug life considerably, taking the risk of a death stick, remember that the platinum element of the glow plug acts as a catalitic element to help the fuel burn out once you take out the glow driver.

Best regards.

For as long as I have been flying I have used a single NiCad cell for heating my plugs... and it has always worked.

When freshly charged, they make a plug go almost "white"... after that, just yellow... to orange when the cell is almost dead.

Even orange (that's about 1 volt on that cell under load) is more than enough to start any engine.

Heating a plug until it's white hot does not necessarily mean shortening its life. You just have to watch out when running the engine up to full power when the glow driver is still connected. The combined heat of the driver and combustion heat MAY kill your plug.

"Stubborn" engines do not exist... or at least, they're not stubborn because the plug is not glowing white hot.... look elsewhere...

I tried the new glow driver on my little GP07 today. I hand started it with a few flicks. Usually this engine needs an electric starter to get it running. I think it's a case of getting a good ignition on the flick to produce a good force and turn the engine over, as opposed to a dim glow which may not ignite so well or so frequently, and hence it takes more effort to get the engine started.

I stopped using glow starters years ago, I use the glow driver on my power panel. I adjust the glow to a bright orange. I also do not use an electric starter, I always start by hand. The first start of the day usually requires a few "flicks". After that, the engines start with one or two flicks.