Glow plugs

[MartinH]

I think ive had about 2-3 glow plugs now and all seem to go just when i'm starting the heli, why is this and do they fail mid air. Ive had the odd one go after a lean run.

[rapidgaz]

never had 1 fail in flight, but when you say the go at the start, what glow plug driver are you using

[MartinH]

Sorry for the lack of info. I use the align 2-1 and they havent gone all at once but over a peroid of time, as I said usualy for me after a accidental lean run.
I think I read people see glows as consumables in that there one thing your expected to change often.

I havent a problem it was a general question thats all

[sacko]

Depends how many you have gone through, I am now on my second one in about 6 months or so.

Check you arent running lean or there isnt a bit of dirt from the muffler knocking out the glow plug.

[Geek]

Check engine bearing
Yes they do go in flight but not much
also engine flooding makes plugs die. (hydraulic lock etc)

[rapidgaz]

some of my plugs seem to last foe ages, all depends on the tune of engine. lean runs def kill the plugs. i have nticed on the 2-1 reg that if the plug has gone the 2 lights come on but the 1 goes out very quick. try disconnecting the red lead from the plug and press the button

[MartinH]

some of my plugs seem to last foe ages, all depends on the tune of engine. lean runs def kill the plugs. i have nticed on the 2-1 reg that if the plug has gone the 2 lights come on but the 1 goes out very quick. try disconnecting the red lead from the plug and press the button

Yes I have noticed that and its very helpful.
You press the ignite button but the second (earthed) light doesnt come on until the last few seconds and then both go out.
The first time they came on I was a little cluless but upon checking the plug I knew it was something handy to look out for.

Check engine bearing

Bearings are fine, there pretty new and I check them atleast once every 2 weeks through general engine maintenance etc.

also engine flooding makes plugs die. (hydraulic lock etc)

Dont seem to get any locking now for some reason .


A better explanation of the question becuase its early and I cant explain myself properly sometimes lol :/.

why do plugs seem to fail after a lean run.

[rapidgaz]

prob due to to much heat, but not sure

[Andy from Sandy]

why do plugs seem to fail after a lean run.

Because the combustion chamber has overheated. The element then usually looks a frosty white colour.

The reason a plug doesn't normally fail in flight is because it is kept glowing by the chemical reaction between the platinum and the alcohol.

The plug fails during starting the engine because it is being stressed by passing a current through it like a bulb element.