abaser

Hey guys, another question. On my OSmax 40 I can fly all day long, but when I go to fly on another day, I have to change the glowplug becuase it has burn out. Any ideas on what would cause this? Usually when I fly I only have time for about maybe 5 flights and then I put it up but during those flights I have no problems except maybe 1 deadstick. Ive tuned and tuned the engine, but then again, being a self taught newbie, I dont know if Im even tuning it right. I feel like im doing something wrong due to the deadsticks. So any help is appreciated.

SMOKEFAN

Im thinking a hair lean on the bottom end. Im willing to be riching it will help. Try 5 degrees on the needle

stang

My Feedback: (1)

Glowplugs burn out. They burn out from contaminants in the fuel, too lean a run, plug voltage too high, vibration and sometimes I think just to annoy you. It's just a fact of life so carry a couple of spares.

cutaway

If 5 flights are trashing a plug, you're running too lean and/or using too much nitro.

abaser

In that case Im gonna need the warehouse. Out of the past 5 days of flying, Ive put in 5 plugs. Each before the first flight. Im thinking that its got to be something with my fuel mixture or something. But then again, thats why Im asking. I dont really know.

abaser

What % should I beusing I wonder? Im usung 15% at the moment. Thats what the guy at the HS recommended.

rcdude7

My Feedback: (264)

Are you sure you are not using too much voltage to light your plug?

SMOKEFAN

Im tellen ya richen that bottom end. Start it and warm it up. Then hold the model nose up at full throttle and see how it sounds on top. You may need to go a click or 2 rich on top also.

What engine and what glow plug are you using?

abaser

Not sure. thats why Im asking. looking for any ideas. I am using a tower rechargable plug ignitor so I would think it shouldnt be too much, but I will try to check it.

abaser

Its an OS 40 max and to be honest, Im not sure about the plug . Im gonna have to check and get back to you. Im just using what the guy give me when he give me the plane. guess I should've paid attentionto them. My last one is in the plane in the shed. Ill look after while and let ya know.

SMOKEFAN

should be a hot like an A3. Your igniter isnt the issue if your using a proper unit. Its either your settings or the plug itself.

abaser

Thanx for the info onthe plug. I had no idea what it should be. By the way, I think you are right on the money about the fuel. Im used to working on fourwheeler motos and being lean will do about the same thiing the spark plugs. Just not that familiar with the glow concept.

da Rock

If your exhaust isn't visible at wide open throttle land and adjust the highspeed needle. A couple of clicks richer is what you want.

The glowplugs you got with the plane came in individual packages, unopened, right? If they were used, all bets are off.

Try a new OS#8 and a good highspeed needle set.

How to adjust the HS needle on the ground:
With a warmed up engine at WOT, slowly richen until you're absolutely positive the engine is running too rich. It's easy to tell. It was screaming and richening slowed it down.
Now slowly lean the needle.
It will speed up (or you were wrong about it running too rich).
It will continue to speed up as you lean it out.
After awhile it will start to slow down. You've just found out where the "way too lean" setting is.
Quickly turn it back out richer 3 or 4 or 5 clicks.
If you can see the exhaust has a touch of smoke, fly it and look for exhaust in the air. If none, land right away and richen a couple more clicks and go back up. You ought to be close to a good setting.

Every takeoff, look for a bit of exhaust. Anytime you see none, the atmosphere that day has changed enough that you need a click or two richer. It's usually a cooler day than the last you flew.

As the days get warmer, your setting is going to get richer from session to session.
As the days get cooler, your setting is going to go leaner from session to session.
Most sessions won't show any change if you're flying often.

Gray Beard

My Feedback: (-1)

It could be too lean but if it was flown, landed then just put away it could be a couple of other things. As an engine gets older they start leaving a bit of gray mater flowing out the pipe, that's wear in the engine and it can short out a plug, little bits of left over metal. If you are using after run oil it too can get into the plug and short it out. You can try running your engine dry after landing and before you pack it up and go home without adding any after run oil. The .40s can be run from zero nitro up to 15% or even 20% if that's what you have. I run 15% in everything and don't give it any more thought. The plug of choice in most 40s is the OS #8 or the A-3, I have used them both but the #8 is what I run in every two stroke from .40 up.

abaser

Da Rock: Thanks for the step by step instructions. Its never been explained like that to me before. I can tell you now I did not see any smoke out of the exhaust so thats probably it. Thanx again.


I am using 15% and its a new engine. I got it in the box, but the instructions were missing. The plug looks like it has a 6 on it. but the stamp isnt very clear so it might be an 8, I just cant tell.

Thanx again to all that have expressed their thoughts. Ive learned quite a bit today.

SMOKEFAN

Just ensure you have a 3 or an 8 and richen that motor up both top and bottom. I find Blowing plugs is usually lean on the botton especially when blowing them when starting. Keep us posted!!

Rodney

A Fox Miracle plug will work very well too. Question; does the plug (the bad one) draw any current at all? Can you see a glow when you attach the igniter to the plug? If so, you could have some contaminated fuel that is coating the element in the plug so that no catalytic action is taking place. As you probably know, it is the catalytic action between the elements that coat the coil in the glow plug and the alcohol that keeps your engine running after removing the igniter. If you see no glow (no current being drawn) when you attach the igniter, then the probable lean run is truly burning the elements out of the glow plug.

ivyspoppy

Try using Fox idle bar plug or a Fox miracle plug, Thats what I use in all my glow engines and I never have plug problems.Been using Fox plugs for over 30 years.

fly24-7

As others have said, it sounds like you're running the engine too lean. I've had glow engines run multiple flying seasons without having to replace a plug. The rule of thumb that I've used is to lean the needle out until maximum RPM is reached, then turn it back towards rich until you see a 300-500 RPM drop. This is a good zone to continually run the engine at. Good luck!

SMOKEFAN

Im going to chime in again and give props to the fox miracle plug. They are outstanding quality plugs and priced decent aswell. Shouldnt need an idle bar plug though.

rcpilot007

My Feedback: (646)

Sometimes a very small pin hole in a fuel line that is very hard to see Can cause top end lean runs and mess with your plug also a loose or unsealed carb base.Just for the heck of it change out the vent and feed lines also make sure the clunk is not touching the very back of the tank as that will cause lean runs in heavy verticle maneuvers. Happy flying...rcpilot007

carrellh

Exactly which engine do you have?
40 LA
40 FX
Something else?
You should be able to download the manual from http://www.osengines.com/manuals/index.html

I think the 40LA originally came with the A3 plug. OS recently renamed this plug to #6
I think the 40FX originally came with the #8 plug.

The #8 is a slightly "cooler" plug than the #6. It is possible that switching to a cooler plug will help. As others have written, I think your mixture is too lean for the fuel and plug combination. I use 15% nitro and the #8 plug in my two stroke engine and the plug lasts a long time.

ArcticCatRider

My Feedback: (6)

Just richen it up both bottom and top end. You shouldn't have any deadsticks...

On a sport engine, with sport fuel you should get a loooong time out of a glowplug. I have some that are 3 or 4 seasons old and still running. Unreal...

Not saying you'll get this, but you should get at least one season

abaser

Rodney: You can actually see the element is clearly broken. Every one has broken right at the tip of the plug about one coil from the tip. Its funny that they are all broken in the exact same place.


Its a 40 LA.

SMOKEFAN

Yup your lean and the #6 or A3 is what you want for that engine.