Quick Question please if I may...

How do you set the mixture setting (using ASP 46)? How many turns etc. Engine has been run in already.

Korps,

There is no magic setting each engine is different. Try starting with the needle valve at two turns open that should be on the rich side. Get the engine running and lean it out until it just peaks. Its better to run a bit rich than too lean which most often ends up the engine quitting and a deadstick landing.

Hopefully the low end or idle mixture is properly set so the engine comes up to full power smoothly when the throttle is rapidly advanced. If not that will need to be adjusted as well for good operation.

Just too make sure by two turns you mean...

The needle turned tight down the two FULL (360) turns? What happens if engine is too rich?

If the engine is too rich, it will die when you give it throttle, or bog down. Yes, the two turns mean tighten the needle until closed, then loosen it two full turns or 720 degrees.

try this ...... http://www.rcgroups.com/forums/showthread.php?t=205602

Okay I officially gave up with my Edge, we set the mixture this morning again and it sounded fine - although it wanted too die every now again after it's been idling for a couple of seconds and when you give throttle it goes again. We got it too that it didn't do it anymore (but we probably didn't let it idle long enough) and decided I'm going too take it up - BAD DECISION! Gave full throttle and off it went it started too choke just before the end of the runway and I decided it's either ramping it over the pile of ground at the end and hope it doesnt hit a hole or let it go up and hope for the best - next BAD DECISION - it decided too push it. It went up and choke choke it died and stalled completely only a couple of feet from the ground and went into a nose dive - I flared just before the ground and got the nose a couple of inches up but it still hit...

The one side of the prop broke off, the cowl got cracked at the bottom and on inspection I saw the top right corner of the firewall also broke loose.

I don't know what too do anymore (I have checked the fuel tank and all the tubes) I thought it was the mixture setting which was at fault but seems I was wrong. The engine starts without a problem but doesn't want too idle and as soon as you give throttle for take off - a second or two afterwards it chokes.

Going too take the plane too the hobby shop and ask them too please fix it for me and also maiden the plane. Otherwise I'm going too write it off before its proper maiden voyage.

I did fly my Stryker (with my LIPO) again this morning afterwards with the wind coming up - was great fun!

You need someone with experience with these to show you. Have them at the field or take the outfit over to their house. The Hobby shop could probably tell you who to contact.

Korps ... the base setting for the ASP 46 is about 2-2.5 turn on the HSN and about 3-4 turns on the LSN. I found that on 15% nitro I am about 1.75 turns out on the HSN only.

Hi!
All engine settings are made by ear! Both high speed and low speed settings! This is something you got to learn.
Begin with with a high winged trainer not an Edge or any other semi scale sport plane.
And most important... join a club where you can get help.

Jaka ... the engine does speak to you right? This is something many don't seem to learn. Hehehehe ...

They have a language all their own. Someone experienced could help demonstrate the language by example real easily

School of Hard Knocks Lesson #37: If it ain't running well on the ground it will not improve on its own with additional altitude.

Lesson #72: On takeoff . . . or most other maneuvers . . . advance the throttle slowly and smoothly.

Lesson #73: Heck, don't slam ANY of the control sticks and sliders at any time. On vs. Off is for two-position switches.

Now for the bad news. There are two mixture adjustments on most glow engines. A low idle and a high speed. Some have an air-bleed needle for low/idle. They come from the factory at a generic setting. If you have moved either of both and do not know the factory default settings you have lots of trial and error ahead. I'm not familiar with an ASP 46. As a rulr of thumb move the screws/needles 1/8 of a turn (40º) at a time and "goose" the throttle occasionally when adjusting the low end to keep a good supply of fuel flowing. Things like cowls and inverted engines can make engine tuning a bit tougher due to reduced access and increased heat.

You can adjust the "main" needle valve (high speed) for hours and hours but if the low end is bad you'll never get a good transition from low or middle to high speed. Most engines have a bit of tolerance for both settings. Some are very finiky.

It's not my first plane - I started with a Stick and flew it for a while - the Edge was my next plane after my Stick. The engine, receiver, everything was build over from my Stick. So I'm not totally new too RC planes - I just put it in beginners thread because I didn't know where else.

Quoted from Charlie:

"School of Hard Knocks Lesson #37: If it ain't running well on the ground it will not improve on its own with additional altitude."

Believe me I know this lol - but I just never listen too myself.

"Lesson #72: On takeoff . . . or most other maneuvers . . . advance the throttle slowly and smoothly."

I do this.

"Lesson #73: Heck, don't slam ANY of the control sticks and sliders at any time. On vs. Off is for two-position switches."

This I know too.

"You can adjust the "main" needle valve (high speed) for hours and hours but if the low end is bad you'll never get a good transition from low or middle to high speed. Most engines have a bit of tolerance for both settings. Some are very finiky."

Yes and I have no clue about the low end adjustments - that's the reason for me taking it too the hobby shop. The guy actually picked it up a couple of minutes ago and said they will sort it out - I don't have too worry. He also thinks its the low end which needs too be adjusted. But they'll put it on a bench and do it.

The engine's performance when you advance the throttle from idle to high speed is called "transition", because the engine is transitioning from the low speed needle to the high speed needle. If an engine is running fine at high speed, but having problems during transition the problem lies in the low speed needle, because the engine's mixture (% of fuel vs % of air) is controlled at that point by both needles. When tuned correctly your engine should transition smoothly. If it coughs and splutters in transition it's probably running rich (too much fuel, not enough air), if it simply dies or hesitates it's probably running lean (not enough fuel, too much air). If it idles nicely for a minute or so then slowly loses revs and dies it's probably rich - when this happens it's called "loading up".

Setting your low speed needle can be awkward but it's not that difficult when you're used to it. First we'll set the low speed needle roughly so it's close to right. Adjust your throttle stop screw till the opening in the throttle barrel is about the width of a T pin (a bit less than 1mm). Connect a long-ish piece of fuel line to the carburettor. Screw the low speed needle in (lean) all the way till it bottoms out (don't force it, turn it gently). Then start blowing into your fuel tube and turn the low speed needle out (rich) till you can just hear your breath escaping in the carburettor. Connect the engine back to the tank, and start the engine, leaving it to run for a minute or so till it's at operating temperature. Pinch the fuel line, and listen to the engine. If it runs normally for a few seconds then revs increase the low speed needle is rich, turn it in a small amount - about 1/8 of a turn. Let the engine run for a minute to settle and try it again. Repeat this until the engine speed doesn't increase but it just sputters and dies, which shows it's now lean. Adjust the needle back out till it just starts running slightly rich. After this you'll need to adjust your high speed needle again, as it will have been affected by the low speed needle's adjustments. You can use the same pinch technique to test the high speed needle, but it will react much faster as it's drawing more fuel at high revs.

Remember you want both needles to run slightly rich, as the engine will lean a bit out at altitude. When you're happy with the way the engine runs on the ground, have an assistant hold the plane level while it's running, then advance the throttle to full speed and have your assistant hold the plane nose up for about 30 seconds. The engine should either maintain the same speed or increase its revs slightly. If the engine dies in this position do not fly it till you've found the problem, which will probably be a poorly connected pressure line from the muffler to the tank, or possibly the clunk (fuel pickup) may have moved forward in the tank during a hard landing.

While doing this tune up, it's a lot safer to stop your engine before adjusting the low speed needle as the carb is very close to the prop and the low speed needle is often a fiddly screw set into the throttle arm. The other thing is to check your carb over completely before you tune it. I drove myself crazy for days trying to tune an engine which was behaving erratically, only to find the barrel retention screw was loose, allowing the barrel to slop around in the carb. Check all the screws are where they should be, and that the carb is well sealed against the engine's crankcase as an air leak there will make it impossible to tune the low end, even though the high end will run just fine.

Could this be the reason why when you have the plane on the ground and it starts too die you just give throttle and it goes again, but as soon as you are off the ground on take off and the engine starts choking, no matter how you work the throttle, it just dies instantly?

Thanx for all the info guys. I decided too leave this one for the experienced people. I will definitely keep all this information (print it out or save it) for the future - either when I need too tune my engine again or whatever the case might be.

Something which came up in my mind and someone in another thread did mention the fuel could be an issue. I used, I think 5% fuel - well the last fuel I got from the shop and also the fuel I started using when I got the Edge was different in the sense of colour and smell. Usually the fuel I got was redish in colour and the last batch was a light orange colour. The hobby shop owner said there is nothing wrong with the fuel - that specific batch's colour only differed from the normal, but the fuel mixture was the same. It doesn't make sense too me, but who am I too argue. Is it possible for the colour too differ and the mixture too still be the same?

Could this also be the problem for the cutting out of the engine the whole time? The last tank I flew with this engine (on my Stick) before putting it into the Edge was with the "redish" fuel and it worked fine.

The colour comes from the brand & type of synthetic oil used in the mixture - methanol and nitromethane are clear and castor oil (if you're using it) is a light brownish colour. Generally it won't make much difference what oil's in the fuel (as long as it's an oil meant for glow engines of course!). Using more nitro than the engine requires will rob a little power, as will too little but again that's not a significant difference. Fuel can "go bad" if it's left open to the atmosphere too long, especially in humid weather as it absorbs moisture from the air. There's no visual way of telling if it's absorbed moisture, and as far as I know there's no way of removing it either.

If the engine's playing up on the ground and getting worse in the air chances are it's running lean (either on high or low speed needles, or both). This is bad for several reasons... it makes your plane crash, and the engine overheats (running lean = running hot) and doesn't have enough lubricant.

Hi Korps

Follow the advice for engine tuning posted by Sandmann AU, I also have an ASP 46 which came with no instructions in the box!!! I emailed ASP in the UK (just engines) and they responded that ASP and other Chinese made 2 strokes prefer a little nitro and require some castor oil in the fuel. It doesn't need to be all castor - just some. I run mine on a blend of 18% total oil (9% synthetic and 9% castor) with 10% nitro. The motor would run fine with no nitro but starting was difficult, added the nitro and it now starts first flick every time - I have never had to use an electric starter on my ASP.

One of the engine guru's at our club set the motor up for me and I have never had to touch the LS needle since. It does sound like your LS needle was a little on the lean side.

look forward to reading about your succesful maiden.

Andrew

Just spoke too the guy at the hobby shop who had a look at my plane. The feedback was as follows:

They set the low and high end needles and made it a bit on the rich side - he said he feels safer with the engine like that because as soon as the engine gets hot it seems as if there is no pressure/back pressure in the exhaust (Apparently this could be that the engine got too hot at a stage). They tested the engine in the yard and it's working fine now..He said the engine will tend too rev higher when the plane pitches up - but that is the way it should be he says. When flying level and straight it will fly on a more of a rich setting. Apparently the exhaust was a bit loose (but I think it was because of the nose dive it took into the earth). Apparantly (I think he said exhaust gasket) was also broken - don't know if this was before or after the "crash".

They are going too maiden the plane hopefully this weekend. I'm hoping for the best.

Glad it's working right. If it's been running lean, it will have overheated and worn the internals more than normal but it should still be fine - you might have shortened it's life a little is all. Engines will usually speed up slightly when they pitch up - harder for fuel to get to the carb, so the mixture leans out slightly (that's one of the reasons to run it slightly rich normally). A leaking exhaust will only make a bigger mess of your plane - shouldn't affect performance too much (unless it's a really bad leak - that would reduce your tank pressure). Exhaust gaskets are a waste of time - when the engine's running the vibration & heat compress the gasket which make the exhaust loose, then the gasket tears and falls out. Generally mufflers seal up to the engines just fine without a gasket - if you want you can use a little high temp RTV silicon to help seal it.

Good luck with the maiden - let us know how it goes.

ABC engines have a universal break in procedure that works. Make sure that the engine is completely broken in before messing with the low speed setting.

For a .46, use a 9x6 prop...this will allow the engine to get into a 2 cycle scream without a huge heat build up.

Set the engine for wide open throttle and leave it that way for 2- 3 tank fulls of fuel.

With the nose of the model pointed up, bring the engine up quickly to peak rpm, then back the high speed needle down to the richest setting that allows the engine to run in a clean [but rich] 2 cycle scream. You don't want to hear any "4 cycle" blubbering. If you are using fuel with a significant castor content, there should be smoke billowing out. I add enough castor to a fresh jug of LHS fuel to top it completely off.

At this point, monitor the engine's rpm for any signs of sagging and periodically sample the exhaust spray with your finger. The idea is to see the spray clear with no signs of metal sloughing off [mainly the piston]. It is common for the engine to REQUIRE the needle to be opened up slightly during the break in because as the piston / liner fit becomes optimal, the fuel requirement will increase [more horsepower being developed]. Keep doing break in runs at full throttle and with the tank under the engine [not level with] until the needle setting stabilizes and the exhaust spray runs clear.

Now you are ready to play with the low end settings, the high speed will also be slightly effected by too much of a low speed correction, so bear that in mind. Always set the high speed with the nose of the plane pointed up.

Fuel that has absorbed more than 10% water will not run well and can be frozen, then the ice that forms at the top skimmed off. Fuel with up to about 10% water will run decently, this fact was presented in a magazine article years ago, I believe it was published in Model Aviation or RCM?

One way that will usually give you a clue as it too lean or too rich is. After adjusting high speed needle lift plane so nose is vertical. If too lean it will lean out even more and heat up. Open needle another 1/4 turn then try again. If you continue to have a problem it maybe it's sucking air someplace that is leaning it too much. If so find outwhere the air leak is or will never get it tuned. Once you get it running perctly at high full throttle then you can adjust low speed needle (not before). To adjust low needle bring the throttle trim up a bit so it's running a bit fast at idle. now bring trim down a bit to slow it to normal idle. If still running well. (you should be able to ell by the sound if it's loading up or going lean). If all seems good then advance throttle quickly from idle. It should come right up smoothly. If it quits then idle needle is too lean, if it sort of gurgles coming up, too rich. You will get just takes practise and a good ear for what it should sound like. If none of this works,GO ELECTRIC HAA HAA.

And that is the reason I love my Stryker sooooo much - even with it's defected aileron. Was a great way too relax after the incident with the Edge