how would i no ????

[nitro_freak_123]

as the title says 'how would i no ' if I'm using the wrong glow plug wat are the symtoms of using the wrong plug

i usually us a os a3 plug but i thought ill buy a os a5 what a diffrence this has made hardly run it without the glowigniter attached.

it starts up ok but when i take off the glowigniter an try to pull off it justs stalls I've been researching on google about it and it said only use a os a5 plug in airplanes or .60 or bigger engines is this true ????

can some1 shed some light on this please thanks in advance


nf123

 

[Badfish]

What are you using it in?

http://osengines.com/accys/glowplugs.html

^ tells you pretty much what its good for ^

 

[olds97_lss]

A3 = hot
#8 = medium/hot
#5 = cold

According to my OS 21 RG manuals, the #5 is recommended for it. The 21 RG is a land engine. I use #8's in it with good success. Running #3's in it tends to give me high temps and detonation issues.

The temperature of the plug is the timing control that we have for these engines. Combined with nitro content and head shims. Plugs are the easiest way to adjust an engines timing. Some like the fuel to ignite early, others don't. Higher compression engines like it to fire later. When the fuel is under a higher compression, it's easier for it to ignite, so using a cooler plug keeps the timing where it should be.

Basically, you want the fuel to explode a few degrees before the piston is TDC so it burns the majority of the fuel/air mix in the cylinder before it pushes it down and blows it out the exhaust.

The compression, nitro content, head shims, amount of fuel/air in the cylinder judge what plug you want to run.

When you use to hot of a plug, the fuel/air detonates to early and it makes the piston want to push itself back down before it reaches TDC. To cool of a plug and it's firing to late after the engine has reached TDC, so you get a really rich "feel/sound" when running. A lot of the fuel gets expelled out of the pipe instead of being burned in the cylinder.

What engine/fuel are you using?

 

[nitro_freak_123]

bad shall i stop using this plug and get a new1 tomorrow would it damage my engine if i still used it


i got a pro.15bxs pullstart engine (thundertiger)

olds I'm using

http://www.modelsport.co.uk/?CallFunction=ShowSpecification&ItemID=23795 (fuel) at the moment but i usually use this

pro.15bxs pullstart engine

i got a thundertiger ssk

can some1 tell me the perfect plug i should use init please

thanks nf123

 

[Badfish]

I dont think that it would damage the engine. You may just need a new plug, that could be why it stalls when you take the igniter off

oh and do yourself a favor, next time you go to your LHS, pick of a few plugs instead of one.

 

[olds97_lss]

I would go with the #3 or #8. If your running less that 20% nitro, go with the #3. If your 20% or more, try the #8.

 

[nitro_freak_123]

olds

do u mean os 3 or 8

I'm DULL SEE

 

[Monkey Wrench]

 

[nitro_freak_123]

monkey what does that mean bro ?

i no what u mean olds just teasing thanks for all the help anyhow

nf123

 

[rocknbil]

LOL Monkey . . . that's going to leave a mark.

THERE IS NO PERFECT PLUG.

Re-read olds' first post. You start with the average "best guess" and work from there. Start with the OS 8 he suggested and have others on hand. The only way to find the "perfect" plug is to experiment.

A good starting point is to pair HOT plugs with low nitro content, 15% or less, COLD plugs with high nitro content, 30% or more. A MEDIUM plug will work well from 15% - 30%. The only info we can guess at from the link you posted is that that fuel is 16% nitro, it doesn't specify the nitro content in the sales pitch. Hence an OS 8 or a 3.

Long and short plugs - a long plug in a head designed for a short plug will NOT hit the piston, you will give up a tiny bit of compression, but not enough to drastically change the way the engine runs.