Glow Plug Failing

[Aidi]

Howdie,

What would be a cause of a glow plug (.50 Hyper Engine) blowing when powering up for the first flight of the day?

My 600 seems to have developed a nasty habit of blowing the plug when i go to start it for the first time. Once i have changed it, heli starts and will do all day long. Leave it a couple of days and it will more than likely blow again.

Any ideas or suggestions on how to stop this from happening?

Rgds
Aidi

[Tim Procter]

I have had a batch of useless Enya No:3 plugs Aidi doing just the same.

Replaced them with OS No:8 and all is well again.

Enya No:3 has been fantastic in the past but the latest batch are utter crap.

[waveydavey]

Isn't that bizarre, I've been going through Enya 3's like theres no tomorrow when I've rarely had to change one before.

[David Drew]

I was persuaded to try an Enya 3. Longer lasting they said....yeh, like one tank

OS8s for me at present.

If left standing, could it be crud in the fuel? Settling out and then blowing through.

Rotten fuel lines causing silicone to wash through?

David

[bigbas]

have you checked the voltage for youre glow supply as the day progresses the voltage drops i know enya plugs are not very voltage tolerent as the os variant

[Aidi]

After a chat with Trex-Pedro, it could be my 2-1 Regulator causing the problem. Plugs seem to blow whenever i have put a freshly recharged battery. I'll try charging the battery slightly below full and see if the problem still exists.

Rgds
Aidi

[Andy from Sandy]

I was persuaded to try an Enya 3.

Obviously I don't know how much you know about model engines but do some searching and you will find simply changing a glow plug (especially through persuasion) will not always yield good results.

Engine capacity, compression and fuel blend all have a bearing on which plug you should use. In general when using high nitro content a cooler plug should be used.

If when you run your engine using an OS 8 plug if it idles nicely, spools up without hesitation, produces optimal power, runs smoothly and just sounds right then changing to a hotter plug is probably going to result in the engine not running as good.

The enya 3s may be short lived because the timing is too far advanced and the way the engine runs then damages the plug.

[SteveH39]

I knocked out 2 enya 3's recently, turned out to be a split in my tank clunk line drawing air and leaning the engine even though i run a header tank, swapped both clunk lines and been ok since, i do like the enya plugs though, chap at the field last night tried an os8 in his new hyper 50 and it ran like crap, swapped to an enya 3 and improved no end.

[waveydavey]

The enya 3s may be short lived because the timing is too far advanced and the way the engine runs then damages the plug.

If that were the case Andy and nothing has changed on my heli how can the above be correct. In fairness I have changed fuel, still 20% though could that be the reason?

[Heliblerk]

Could be debris in the engine. I had this problem a few years back where it blew 2 plugs in quick succession. I think it was a slowly disintegrating piston putting tiny bits on metal into the glowplug ( there was never any coil left in the glowplug ). Then the engine cr@pped out so I never got to the bottom of it.

Also, I find in hotter weather my hyper runs better on a cooler plug (OS 8) and a Enya 3 in winter using 30% magnum. Lost two Enya No.3s last week when the engine was overheating in the warmer weather.

Hope this helps

Andy

[Tom Burgess]

I had this too on a Hyper. Strangely, after changing the rear bearing, the problem was gone

[Andy from Sandy]

If that were the case Andy and nothing has changed on my heli how can the above be correct.

My comment was directed at David Drew. All circumstances are different as you know.

[richieclarkie]

In my experience the two most common reasons to do a plug are running lean and bearings.

If your rear bearing is on it's way then you are much more likely to start going through plugs.

[shaun.e]

I wish I had read this sooner - explains everything!! I have the same problem on my 600NSP and yes the rear bearing is on its way out and I need a new plug almost every session. New bearings for me then, thanks guys!

[rapidgaz]

this has been hapening to me also, my 50 hyper is only 2 month old, and have blown 4 plugs in 4 sessions. on another thread i read that using silicone for muffler can cause this, and this is what i was using