Are you re-using an old prop that has hit the ground? Might be the main vibration source. I have a .46LA and it tends to vibrate a bit also. Other than that, it is a great running engine but not what you would call a powerhouse. It did teach me to fly where my original engine, a magnum .40XL (P.O.S.) only taught me how to repair.

adam_jorgensen, on your update post #16 you said "So I tightened it and no more air comes out. I get a good seal now. So hopefully my bubbles will stop now",well did they? If you have a fuel flow problem, which bubbles in the fuel line is, then a new engine won't solve the problem. You'll just have the same problem with a new engine.

Part of the problem may be the vibration you are experiencing as this will cause bubbles, so if you are running a damaged prop toss it and get a new one. If not, at least make sure it's balanced.

Another question that hasn't been asked is, how is your compression? While 30 flights isn't much time, even the best engine won't last long if it's been forced to ingest dirt due to poor "landings" or crashes due to constant deadsticks. I've had worn engines that would run and idle fine when first started, but as they would warm up and the parts of the engine would expand they would lose compression and would only run in the upper RPM range.

Good luck, keep trying, keep it clean and leave the drill motor and bits in the tool box

The prop I am using did not hit the ground I think, but I could check anyways. I took it for a flight last night and got some improvement, but I still had 3 deadstick landings. I had about 5 successful power on landings, 3 deadstick and it always happened on final approach with the engine idling and the motor not sustaining the idle. It did the "sounded great on the ground" I even ran it at idle for a few minuets to see if it would die. Mixture seemed correct according to the tests. It seems to vibrate most at idle but I mean, vibrations will always be there won't they? I could check the prop but if its not that, than I have no clue what it could be.

don't these things have a problem with the chrome coming off the cylinder? that would tend to make it run junky! just get a new motor, itsa known fact these engines have "issues" and i say fly and leave the tinkering to the engineers!!

just my .02!

john

I have to agree with blue you are spending way too much time on this motor this is supposed to be fun and if you have to worry about dead sticking everytime you fly what fun is that. If you ask me I think the old FP and these new LA motors should be pulled from the shelves.

Hoping that the air bubbles have gone away enough. One thing that no-one has picked up too well is fuel foaming in the tank. If you have hard mounted the tank (i.e. not installed it with a foam wrapper) then the vibration of the engine can cause the fule to foam so much that the engine pulls as much air as fuel. You can also get foaming from the clunk and some people advocate wrapping the clunk in foam too but I have never seen that problem myself.

If you are struggling with setting up the carb then nitro in the fuel will make the engine less sensitive to the adjustments being slightly off. It might also be worth investing in a new plug, I would go for something fairly hot like an Enya No3.

I wouldn't go for a new engine if I were you, I think you need to get experience on how to set up an engine and how to install a sound fuel system...

Good, it seems you are making progress. I did not mention before but you can use the very same pinch test on the high speed needle also. Just give the fuel line a slight pinch at wide open throttle and see what it does. It should either slightly raise in rpm or there will be no change when set properly rich for flight. If the engine sags or dies it is lean. Also, make sure your prop is balanced. Do not trust the manufacturer. Get an inexpensive finger balancer. They only cost a couple of dollars and work well for balancing. If the prop is not balanced it can cause the fuel to foam which can cause the engine to die inflight.

One more thing when you are removing the heater from your glowplug. If the idle of the engine drops quite abit it could be a sign of a plug going bad. Might want to replace the plug.

ok now i know they have fixed the problem already but check these just to make sure your engine isn't one of these ok.

just tryin to help here!

i think they still will fix the old ones for free but i am not sure
good luck and happy flyin!!

http://www.rcuniverse.com/showthread...chrome+peeling]

Who will fix old ones for free?

Could this be a problem? Because my cylinder head and around the muffler has this yellow gold brown substance on it and it won't come off. This may be because of the heat but can this actually be a sign of a bad engine?

I talked to a guy at my local hobby shop, and he said my probelms with my engine always dying on me was because I was fiddeling with the mixture too much and that I am just to leave it alone at all times if I get the right signs if its the right mixture. Well, what if my engine keeps dying on me? Won't I need to adjust the mixture? This is why I keep fiddeling with it. I didn't know that it would be doing more damage to do so. Isn't that what its there for?

On my last flight when I said it was a deadstick, when I was bringing it down, I was running out of runway or field so I had a pretty hard landing that bent the front landing gear. This question is a little of the topic, but I wanted to bring it down before it would hit a gravel driveway that sloped up from the field I was using to takeoff and land. What I did was kinda pushed the airplane down so that it would land before the driveway because I was afraid it would do more damage but I had a pretty hard landing with a loud thump and bent the front landing gear. Should I have just completed a normal landing and let it land where it should rather than trying to force it back on the remaining field or did I do the right move? I really hope this didn't do any damage to my engine futher. Heres how bent the landing gear looks. Is it bad?

The yellow brown substance is probably burnt castor oil most motors that run castor will start to turn brown it's nothing to worry about. As far as the mixture setting I only adjust mine for the first flight, I never have to mess with them the rest of the day. As far as your dead sticking all the time you should set your mixture a little rich on the ground it will lean out in the air for 2 reasons. One the prop unloads going through the air and two as the tank runs out it will also lean out so if you are running at peak rpm on the ground you are leaning out too much in the air and that's why your are dead sticking. Make sure you have a real good smoke trail coming from the exhaust as you fly over the runway no matter what you should always see smoke if you don't land immediately or you take a chance of burning up your engine.

I almost forgot as far as your hard landing sometimes you have to do what you think is right we all have hard landings the worst situation is flaming out on take off all you can do sometimes is try to crash as soft as you can and hope you don't do too much damage.

Success finally! Bringing this topic back to life again, I am pleased to let everybody know that I think I finally have the right setting on my plane, and sorted out the idle problem. My last 7 or so flights have had no engine failures. Here's what I did. Well, I listened to the guy at my local hobby shop who told be that my problems were in that I was always fiddling with the mixture, and I should just leave it. Well, I haven't touched it in the last 5 flights and my engine hasn't quit yet. And about the idle, I figured that it was idling too slow, so I increased the idle with just some trim and it won't quit on idle anymore. Although, my plane still tends to come in hot sometimes so the idle could be slower to allow for the slower speed, but then the engine would just quit. I'm happy where it is now. Thanks everybody for your help and I hope that the engine failures will be much less now. I enjoy flying so much more now that I know that my engine won't be always on the verge of dying all the time. You should have seen me last night. I couldn't put my plane down.

But I shouldn't say that I haven't had an engine failure in those last 7 flights because my last one for the night last night, quit but it was not any mixture or engine problems so that was a very big relief to me. I had a hard landing nose down that stopped the engine because the prop hit the ground. Every time I have a nose down impact, I discovered that the clunk in the fuel tank flips forward so that its stuck in a U shaped position facing the front of the tank. It was fine when the tank was still full with fuel, but when the fuel got low after 16 minuets of flying mostly at full throttle, the engine sounded at times like it was going to die because there were big variances in RPM because the fuel would swish back and forth in the tank causing, because of the position of the clunk, when the fuel would be away from the clunk, it wouldn't be getting any fuel so that's when the RPM dropped and then it would rebound again when the fuel would move forward towards the clunk. So when the tank got real low, that's when no fuel went into the clunk and the engine quit. Luckily I was right by my field so no damage there. I'm glad it was something I could se rather than an actual engine malfunction. Is there a way to prevent this from happening, or should I just check the tank every time the nose strikes the ground to make sure the clunk hasn't flipped forward?

Let me clairify just for a second what the hobbyshop guy is trying to tell you. When set up properly you should not have to touch the needles very much. But, you have to get the engine setup properly first. Once set properly you will hardly have to touch the low speed needle. All you will have to do is peak the high speed and set it a little rich on the first flight for the day. The pinch test works great for this. On the low speed needle when set properly you should be able to idle in the 2000 to 2500 region all day without dieing or loading up. After about 8 to 10 seconds you should be able to smoothly roll the throttle (1 second to high throttle) to high rpm without any hesitation Increasing the idle speed only compasiates for an incorrectly adjusted engine and makes for a plane that will not slow down on landing. When the plane is setting there idling you should be able to tell what it is doing. If it starts to loadup and slow down it is rich. If it starts to speed up it is lean. Adjust the low speed needle or air bleed to correct this. Turning the air bleed clockwise will richen the mixture and counter clockwise will lean. Remember the low speed needle affects the high speed setting but not the other way around. You have to learn to setup an engine correctly, just leaving the engine alone will not do anything. An incorrectly setup engine will not fix itself.

If you keep having problems with landing speed switch to an 10x5 prop to slow the plane down on landing.

I don't believe anyone has said anything about fresh fuel, fresh glow plug and a freshly charged starting battery.

Yes they have mentioned this previously. But does the Enya plug have an idle bar. PLEASE use a plug with an idle bar!!!!!!!!

The LA 40 does not need an idle bar plug to run well. Most engines today do not need idle bar plugs to run correctly. Some actually run worse on idle bar plugs like the Tower .46 ABC. Of course this is IMO. Your miles may vary.

I believe the best advice you could get is "have an experienced pilot who knows what they're doing help you". All of this advice you are getting is correct, but the only way you are going to be able to get any real results is to have some "hands-on" help from someone. Although you've been in the hobby for three years, it sounds like nobody ever taught you how to tune an engine. You should never really need to touch your high end needle that much, just one or two clicks each day out should tune it just fine, depending on air temperature changes. You never did state if the air bubbles went away or not. The engine will run when air bubbles are present in the line, but it will never run "correctly". It sounds that you are demanding a high idle. I don't have any RPM numbers, but the engine should idle in the range to where it will ALMOST make the plane roll. The plane should never roll on its own at a good idle. If it does, the idle is too high. As far as needle settings, after you crank the engine and get it to a reasonable idle, run up to about half throttle. Open the needle valve to where the engine will barely keep running, you should do this at full throttle. With the engine at full throttle, the needle valve out enough that the engine is slobbering rich, slowly turn in on the needle until it transitions from slobbering rich to a high pitched whine. DO NOT turn the needle in any farther once you have achieved the high pitched sound, you are now at MAX RPM. Now, turn the needle outward two to four clicks. This will give you a good neutral needle setting. With the engine at full throttle, point the nose straight up. If you hear little to no change, your at a good setting. If the engine RPM drops, your too lean and need to come out on the needle another click or two. Do this untill there is no change in RPM. As far as the air bubbles in the line, if there are any, you've got a hole in a line somewhere. Replace all hoses, even the ones in the tank. The clunk is going to stick in the nose of the tank if the clunk line is too long. With the tank out of the plane, jar the tank forward as if the plane hase nosed in. If the clunk shifts to the front and sticks there, the line is probably too long. And then again, the line may do that every time no matter how long it is, depending on the impact when you hit the ground. In this case, the best solution is to not nose in, PRACTICE on those landings! You have gotten a lot of good advice from all of these guys. I have a 40 LA that was my first engine. It has been nose first into asphalt, nose first into the ground about six inches half a dozen times, and submerged in water and mud a time or two. The engine still runs perfectly even to this day. I've come a very long way since then. It is not a powerhouse by any means, but in "my opinion", they are very tough, reliable engines when tuned correctly. Make sure the engine has good compression, meaning you should have to exert a bit of force on the prop for it to turn over. If it turns over rather easily, you have probably run the engine too lean one too many times and need a new one. If it feels reasonably tight, you're in good shape, just make sure you run it rich enough from here on out. Remember, ther is no substitute for hands on knowledge. You can get a lot of good advice from RCU, but sometimes with so much input from different people, you can be led away from the real problem.

Good luck and don't get frustrated,

John

Excellent input from Yard Dart. Where I was only using the pinch test on my two-strokes, I think that running full throttle, then going rich till it blubbers, THEN going lean till it peaks again is a valid approach, which I will now follow. It is so much more precise than just a pinch test. Then the nose-up test fine tunes it in.
As far as the engine failures Adam is/was having, with the number of hard landings you had, it is IMPERATIVE that you hold the plane nose-up and SHAKE vigorously to jar the clunk to the proper position, or the engine will quit in flight. With all the good input since your first post I think you will have consistent good flights unless the engine breaks.
George

There's a couple of points not mentioned by others that I think would be helpful to you at this stage of the game. Just running the engine tells you nothing.

First, there are a couple of way's to verify that your idle mixture is correct.

While the engine is running at idle, hold the nose up. If it's too lean it'll die. If it's too rich, it'll speed up and run better. Now, do the opposite by holding the nose down. If it's too rich, it'll die. If it's too lean, it'll speed up and run better.

Final check. Run the engine up to full throttle to clear it out, then back to idle. Let it sit at idle for 10-15 seconds, then snap the throttle to full power.

If it dies or hesitates, the idle mixture is too lean. Richen it by turning the air bleed screw IN, not out. The air bleed controls air, not fuel so it works the opposite of the main needle valve. The main needle valve only controls full throttle. The air bleed controls everything from idle to 7/8 throttle.

Check to make sure that you've got at least 1/2" between the back of the fuel tank and the clunk. Any less than this and the engine will run lean.

Also, if the fuel line runs through a firewall, make sure the fuel line slides FREELY through it. If there's any resistance, the fuel flow will be restricted and the motor will die.

Make sure you're running tank pressure from the muffler. O.S. engines will become unreliable without it.

Lastly, change to a different glow plug. You can spend the big bucks and buy O.S. plugs, but I've had excellent results with Fox R/C longs and K&B R/C longs.

Glow plugs, like spark plugs come in different heat ranges. Maybe the one you're running is too hot and is overheating the motor. The coldest plug is the McCoy MC-9, but it's pretty pricey. Next is the Fox R/C, followed by the K&B R/C long. 4-stroke plugs are the hottest because they need to keep the fires lit every other turn, so don't use a 4-stroke plug.

Dan

Air bleed carbs benefit from plugs with idle bars! When you can fine tune a carb that has a low end fuel mixture screw then you go to the barless plugs.

A lot of guys, when tunning the engine, like it leaned to the maximum rpm. This is fine for racing, but for guys like you and me just trying to have a good time at the local field this may not be the best idea. Try over richening the engine. My experiance with OS engines is that they will run with lots of fuel but are problematic with too little. They need the fuel to cool, so run it rich enough that you still get good power but have a healthy flow of smoke from the muffler. The Richer the better!

You shouldn't need a plug with an idle bar dog. They were introduced when throttling of crossflow engines became possible. If you cast your mind back, the engines of that genre also had a butterfly valve over the exhaust (before the days of mufflers). The idle bar and butterly were there to keep a crossflow running when idling (idle bar?). A modern schneurle ported engine with a muffler just doesnt need an idle bar. It is more likely to cause problems than solve them. The fact that the carb is air bleed makes no difference to plug heat, it just means that the fuel is metered in a different (a bit less precise) way.

As regards the question posed, if you want to stop your clunk coming to the front then you can include a short length of brass tube in the line from the bung to the clunk. Leave a flexible length of tube at each end so the clunk still falls to the bottom of the tank so that the fuel feeds but include enough brass tube so that the pipe can't 'turn around'. Do I need to draw a picture or do you get it?

Hi!
The plug you should use is an OS 8 or a Enya 3! naturally there is other plugs to that works good but these two are the best sport plugs on the market
Old typ idlebar type glowplugs should not be used...they work okey too but idlebar plugs are not needed on modern engines...

Regrading fueltanks...never use just only a silicon fuel hose from the fuelpick-up inside the tank.....the hose will eventually bend forward in a hard landing.
Instead solder small piece of brass tubing to the fuel pick-up clunk and this "bending forward"action will not happen.

When enginetuning is concerned ....this is all done by ear! -This is how you tune engines!
Just listen how they sound and react accordingly.
If you dont know how to do this ...ask for help from someone who knows.

When you tune an engine which is sitting in an airplane its vital that you allways hold the models nose up for a couple of seconds (5-10seconds)! You don't have to shake the model at all....just hold it upwards and adjust the highspeed needle slightly rich.

Regards!
Jan K

I guess I do need a picture as I don't quite understand the process. A picture would be very helpful in this problem.

As for what mixture I'm running at, its a rich mixture becasue theres usually a stream of smoke coming out from the muffler at full throttle only though. Should there be smoke coming out even if its ideling or at half throttle? My last few flights, I didn't even touch the mixture setting and it has run better than ever, so even making sure that its at the right setting by doing the above methods of leaning it untill max RPM is reached and then enrichening it from there I'm afraid of doing because tampering with the mixture before has only made things worse and I don't want to screw up the good setting its at now. I'm still concerned with my ideling being to high though so I will try that method of the plane should not be moving on idel other wise its ideling to fast. I fly off a grass field, so I would have to test it on pavement I guess because sometimes my plane won't move at all even at full throttle on the field, I have to give it a little push it get it going. Its not grass cut for flying airplanes. I don't usually go to a club, I usually fly solo at my own private field. Its great because you get to land wherever you want to.