Glow plug failure!

[panosg]

So what lifespan I should expect from a glow plug guys?
I had 10 flights with a brand new glow plug and today on my 3rd flight the engine will only run with the glow start heating the plug. After the 20 second glow the engine will stall.
Borrowed a club mates glow plug of his 600 and engine was happy again.

So how long do they last. Or am I doing something wrong?

[debrooker]

What did the coil look like in the plug when you took it out.

For instance did it looked stretched and pulled to the side?

[michael_fly_more]

To be honest my glow plugs norm last all year
so should last much longer than the one you had

plug could of been faulty
have found before some times a real rich engine can mess a plug up
Os no 8 seem to be the best plug
just my thought

[panosg]

What did the coil look like in the plug when you took it out.

For instance did it looked stretched and pulled to the side?

Daz din,t take any notice of the coil mate. I just looked the color, and looked just little tanned.
I will have look at it tomorrow and let you know mate.

Thanks

[panosg]

Thanks Michael.

Hmmm dont think is running rich, but might be wrong.
Os no 8 was the one that failed!

[Si_B]

You can get bad plugs, but worth checking you are not running to lean. If I blow a plug, I aways drop the head off to make sure the element has not cause any damage. Sounds like yours is stil intact. What are you using to power the glow?

[panosg]

You can get bad plugs, but worth checking you are not running to lean. If I blow a plug, I aways drop the head off to make sure the element has not cause any damage. Sounds like yours is stil intact. What are you using to power the glow?

Hi Si.

Bottom plate temp is bang on after a flight. I may rich en it up a bit.

Also I ma using a PushGlow Onboard Glow Driver to start.

[GIXERMAN]

plugs can last five minutes or a year or more, also can be a sign of rear bearing going if you keep doing plugs. you can normally hear as bearing starts to go very harsh on idle, and vibes up in the higher revs.

[Si_B]

If you can get the head off without too much hassle, I would have a look. Debris can kill a plug, could just be a one off or a sign that something is not right. I would think you have just been unlucky with a bad plug.

[jimmyhorns]

Probably just a bad plug.

Ive had one similar to that, swapping out the plug made all the difference.

I tend to run OS8s in everything apart from my 4 stroke planks.

[panosg]

Did sound spot on after the plug change.
I may drop the engine tomorrow and have quick look. Don't take that long to do anyway!

[panosg]

So I had the engine stripped down after the glow plug failure and had a good look.piston , liner and bearing all look as it should.
I have attached few pictures of the failed glow plug in case someone can see anything wrong.

[waveydavey]

It looks like it's got very hot at some time and you're running a bit lean as the element is very dull in colour, also whats the brown deposits. I never have that in my engines?

What engine is it and what are the needle settings

[Sheldrake]

It looks like it's got very hot at some time and you're running a bit lean as the element is very dull in colour, also whats the brown deposits. I never have that in my engines?

What engine is it and what are the needle settings

+1 on that! Something not right there hope someone can sort you out soon.

[panosg]

It looks like it's got very hot at some time and you're running a bit lean as the element is very dull in colour, also whats the brown deposits. I never have that in my engines?

What engine is it and what are the needle settings

Thanks Dave.
Engine is a os50 Hyper.
Mixture control screw as per factory settings.
Needle valve 1 and a quarter ish out. Plenty of smoke, nice power but with out sounding too p$$ed off!
Those brown deposits are difficult to see. But taking the picture in macro mode looks horrible! They will scrape out. Makes me wonder if I was running it too rich and that's oil deposits?