Which Glow Plug?
 

Hi guys,
I'm pretty sure this one has been asked a million times, however in my search i can't find where it's discusses on here.
I'm going to get my first glow engine (trying bigger than electric planes for a bit see if i like it) but I can't figure out which glow plug i need to get
the engine will be an OS LA40 or Tiger .46 what do i get? #8 long, short, cold medium heat or hot glow plugs? too many options I'm stuck
I live in the tropics and tempretures over here are around 27-32C (80.6-89.6F) most of the time sometimes slightly higher by one or two degrees anyone got any opins on this?
sorry if this has gone round here too many times to count but I'm in a bit of a rush to make an order and can't spend a couple days digging into the forums properly.

Thanks for any consideration guys.

RE: Which Glow Plug?
 

The basic OS 8 plug is just fine for that engine. I'm sure that there will be others with varied recommendations.

What plug came with yor OS 40 LA? I would duplicate that, most likely it's an OS-8.

RE: Which Glow Plug?
 

I'm gettting a freebe from a new friend, the OS-LA 40 i've not seen it yet and I don't know anything about nitro flying. I'm getting the thunder tiger .46 too just looking for stuff to add to my towerhobbies cart so i can make the order. I see the #8 as being the most widely used according to tower I figured I'd ask here first :) Thanks.

RE: Which Glow Plug?
 

Yup. That will work just fine. Now, if you are looking for a shopping list, you can always pick up a few spares, and one or two spare plugs in other heat ranges. See the below chart.

CGr.

RE: Which Glow Plug?
 

Short glow plugs are for smaller engines with less clearance between the cylinder and the head. I'm not sure where the cutoff for a long plug is, but it's smaller than a .40 so you want long plugs.

OS8 is a good standard. You can use a hotter plug for cold weather, for fuel with little to no nitro, or if you want to improve your transition and don't spend a lot of time at wide open throttle.

Colder plugs if you're using higher nitro content, if it's really hot or your engine is running hot, or for larger engines. My 1.20 comes with OS cold plugs. Large engines have more material to hold heat and thus do not need as hot of a plug.

RE: Which Glow Plug?
 

CGRetired suggestion is right on the money.

The LA loves the "8" plugs and will not benefit from a longer plug.

I run an "8" on mine and I have yet to have a single deadstick on the LA .46.

RE: Which Glow Plug?
 

Yeah, the "8" seems to be the standard for smaller engines. I keep a card of 6 in my flight box (as well as a few others but the 8 seems to be the one I use the most).

They last from a long time to a few minutes, depening on how you abuse them.

CGr.

RE: Which Glow Plug?
 

It took me over a year of hard use to burn out a Merlin plug. I prefer the Merlins over OS because they are a full length plug with a slightly longer filament . They leave no exposed threads in the combustion chamber and come in a wide variety of flavors. You can get free shipping on orders over $25 too. His plugs start at just $4.95.

RE: Which Glow Plug?
 

I have been running O.S. #7 Glow Plugs, in my OS 40LA. havent had a hickup yet.

RE: Which Glow Plug?
 

WOW WOW WOW! I never thought i'd learn so much from this one post! you guys are amazing!!!! THANKS A BUNDLE!!! I'm going shopping now hehe! weeeeeeeee :)

RE: Which Glow Plug?
 

I personally like the OS A3, i run 10% omega in all my engines and this plug works great in all of them including my TT GP.07, TT PRO.36, 2- TT PRO.46's, Magnum .15 XL and Magnum .15XLS, OS .40LA. I use a OS #8 in my OS .25FX because that's what came with it.

RE: Which Glow Plug?
 

Personally I like Fox RC Long.

Give this a read.

http://www.scootworks.com/rdrc/gloplugs.html

RE: Which Glow Plug?
 

How does an OS F plug fit into the mix? They claim it's for four strokes, but I found that many guys are using them on big two strokes; I tried it and my engine is running better. Is it longer and hotter than an 8?

RE: Which Glow Plug?
 

The #8 plug is about .17" and the F plug is about .25" counting the washer. Thats very rough measurements taken through the package.

RE: Which Glow Plug?
 

looks like there are very many recomendations.. i suppose i can try them all out at some point ! thanks again guys :) great help here GREAT help!

RE: Which Glow Plug?
 

Thanks Gary.

RE: Which Glow Plug?
 

It is not inherently hotter than the "8", but because of the slightly longer length ( more metal ) it does retain heat a bit better.

It also tends to keep the coil out of the fuel, especially in inverted engines. It also ever so slightly raises the compression too.

Many two stroke engines of .46 size and up now come with longer plugs very similiar to the "F" plug and do run better with them.

RE: Which Glow Plug?
 

Fox calls their "Miracle plugs" "MEDIUM" not hot. That site has several mistakes like this.

Two years ago I picked up three card's worth ( over 30 some plugs ) for about $1.75/ea. Now I wish I had purchased even more.
They have been great plugs in everything from four strokers through .40 2 stroke engines.

RE: Which Glow Plug?
 

http://www3.towerhobbies.com/cgi-bin...&I=LXCB28&P=ML
is this the F plug you guys are talking about? a little more than the cost of a regular #8 wonder if i should try it out hmm

RE: Which Glow Plug?
 

The F plug is useful in engines using low or no nitro also, the Merlin equivalent is called the hosenose it is a #2010 and I have been using the same one in 2 different engines for about 6 months. I find that it can really clean up the running of a low compression engine or when I choose FAI fuel.

RE: Which Glow Plug?
 

EH?????

RE: Which Glow Plug?
 

Low nitro fuel needs a hotter plug to run well most of the time. FAI fuel has no nitro.

RE: Which Glow Plug?
 

aaahhhh.. i c i c... i thought two stroke engines or glow fuel engines needed nitro but i suppose you meant other engines.

RE: Which Glow Plug?
 

Most 2 stroke glow engines will run fine on no nitro. 4 stroke glow not as well but it is possible.

RE: Which Glow Plug?
 

( ok head scratching moment... ) Really? and here i thought the nitro was what got it to go in the first place... man going from electric to glow is really something else....
so much to learn (all over again haha)

Thanks a billion!

RE: Which Glow Plug?
 

There must be some methanol in the fuel to run properly. I understand that fuel is ignited by a catalytic reaction of the glow element material and the methanol not just the heat.

RE: Which Glow Plug?
 

All glow engines will run quite well with just methanol and oil (gotta have the oil :D) but to make the most of just methanol you need quite a high compression. Nitro adds power to an engine but it doesn't like much compression so because nitro is cheap in America and everyone wanted to use it, the manufacturers had to make engines with a fairly low compression. I've only used nitro once in the last 50 odd years but that was in a racing event so I can forgive myself there :). So basically, nitro is just an additive to the most important part of the fuel which is methanol.

RE: Which Glow Plug?
 

well now thats an eye opener! thanks! once in 50 years!!!! huh? you been at this a while wow!