Blade-breaker

My Feedback: (4)

Hi,

I recieved a FIRE 40 with the tuned pipe and header about 3 weeks ago. After 2 tanks running on the ground the glow pulg failed. (no it was not lean). The recommended plugs are the K&B but I do not have access to those. I do have OS #8 and 4Stroke plugs. Would either of these work? If not could you please recommend a plug that I may be able to find in my area.

Thanks

bob27s

My Feedback: (19)

Hi Blade..

Thanks for writing...

Any good "hot" plug works well in the FIRE engines.

The OS #8 will work most of the time, but is more of a "warm" or medium glow plug. The engine will run well. If you find the midrange or transition struggling a bit, then you will have to move to a hotter plug.

Hangar 9 performance plugs #3 work well. http://www.horizonhobby.com/Products...ProdID=HAN3020

OSA3 works well too.

The OSFS plugs actaully work pretty well - they are by nature "hot" plugs. We use these sometimes on the piped FIRE90LX to keep the midrange clear on short pipe setups.

Others...

Enya #3
K&B 1L, HP
McCoy MC-59
Merlin HOT
Rossi (nova rossi) #2, #3

Consider the "temperature" of the glow plug as controlling the ignition timing. In general for most engines, colder fires later. If you get a wet fuel charge, the colder plug will tend to gocool (or go out), and you get a transition stumble or a midrange that just seems all over the place.

Let me know how things work out.

Oh........ what prop are you using on your FIRE40 for break-in ?

Bob

Blade-breaker

My Feedback: (4)

Thanks for your response! I do have a few different rossi plugs I can try or I will try the OS4stroke.

I have a 8.75x8 apc prop that I bought from Jett when I bought the engine. This is the one that he had marked as my break in prop. When I was ground running it I showed a peak rpm of about 18000 rpm before I richened it out a thousand rpm or so. Does that sound like the rpm I should be getting with that prop? Also I am running cool power 15% for fuel.

I will let you know what I find.

bob27s

My Feedback: (19)

Yeah, everything sounds good.

Id personally prefer to run Omega (with a tad of castor in it) but you should be ok.

For run-in on the bench, back it down only about 500-600 rpm from peak. For first flights, back down about 700-800 rpm.

Bob