Ye all knowing RC people:

I looked a good bit for this information on Google and here on RCU. I also found the manual for the engine on Evolutions site, but it's pretty generic.

I bought a low wing trainer with an Evolution .61 2 stroke. I pulled the muffler off and there are no deposits in the engine at all. The overall condition leads me to believe the engine is new. Regardless, I am having touble I am trying to work out.

The engine transistions a tiny bit rough, surges in the air, cuts back at WOT, starts perfectly and is smooth as silk once it stabalizes at an engine speed. The surging is very wierd. That is my main concern. It seems to be running lean. If I richen it up on the HS needle it runs a little better, but the funny thing is it putting out a LOT of raw fuel in the exhaust. I puddles and drips out the pipe. After 2-3 flights my entire plane is sticky. In the air there is a steady white plume trail behind the plane. It really looks like it's blowing out as much fuel as it's using.

*I'm running 10% Cool power
*The glow plug is good and clean and new
*Everything appears to be tight, and doesn't appear to leak fuel/oil from anywhere (eg. under the carb)
*The engine has excellent compression
*The "set right needles" have been moved several times in an effort to tune it. I know they are factory preset, but I don't know the history of the engine, so I don't know if they had been moved by the previous owner or not.
*The engine does not get hot, maybe 200 F at WOT 60seconds on the bench.
*I'm running a 11x7 three blade prop.
*Fuel tank is in-line (physically) with the main needle about 2" away. If anything it might be MAYBE 1/8" lower, Maybe.... Hard to tell.
*The lines are new and no bubbles appear to be present. No foam either.

I am not new to glow, but am still learning. I set the LS and HS needles just as I have on other engines. It just doesn't respond to changes like the other engines. I can't figure out why it's running so rich though it acts like it's running lean.

Information or links to other posts would be appreciated.

Thanks all!

Forgot to mention, we worked with it for about 10 flights last night. It runs a little better, but still all the same troubles. I dead sticked one time.

In straight and level flight it surges. On the initial climb it pulls STRONG but cuts back and flattens at around 50ft altitude.

I'm going to get some CP 15% ASAP and try it too.

Far as I know it has the H9 "Super plug" in it now. I have a stock of OS #8's and will try that ASAP although I think it'll be the wrong way to go.

Try either an OS A3 plug, or a 4 stroke plug like the OS F or Saito SS. The A3 will probably be the best one for the engine.

I am going to keep looking, but I just read something about a missing o-ring in the carb from the factory. Any idea what that's all about?

Thanks for the plug recommendations. I'll try to stop and get them from the LHS tonight.

Spiral,


The first thing you must do is to change the fuel you are using...

Morgan Fuels, the manufacturer of 'CruelPower' specifically recommends their own 'Omegaâ„¢' fuel for ABC/ABN type engine, which your Evolution engine is.
Omega has 4.9% castor oil and 12.1% synthetic oil (a total of 17%).

American made synthetic oils in general (Cooper's Ester based oil is an exception) offer a lower lubricity, compared to castor oil.
Klotz rate their own BéNOL at 10 and their Techniplate KL100 at only 5. This means your engine will wear excessively when you use fuel that does not contain castor oil.


Also, castor oil has a 100°F higher flash-point and even more than that higher burn-point. This means you engine will very likely fry if you ever expose it to a 'lean run', with your current choice of fuel...

The running qualities of any engine are also much better with a good measure of castor oil in the fuel... I believe many people consider this hobby less enjoyable, or have even strayed away from it, only because of trouble in engine adjustments and running, due to using all-synthetic fuels and never experiencing the qualities of castor oil...


... Your description sounds like your engine is being run too lean...
The main needle must be adjusted 100-150 RPM rich of maximum, with the plane's nose pointed straight up.

There is no corresponding number for level attitude. This adjustment must relate only to the nose-up attitude!


I am sure Barry (blw) might disagree, but I think the OS A3 is too hot. You need a medium heat plug for this engine and the TowerPower is a good candidate.

Thank you for the information. I'll take that to the LHS when I buy fuel. I'm going to get an A3 and a type F plug and a Tower Power if they have it.

A buddy suggested 15%: but the plane is overpowered as it is, for that reason there's no reason to put additional strain on the motor, and I don't think switching to 15% is going to make it run any better over 10% (unless my 10% is bad or the lubricant is causing problems)

I am going to check the o-ring when I get home too.

Dumb question: If Evolution sells or designed the motor and they say it needs a H9 "super plug", aside from the fact no one carries a super plug, why would another plug work better? I mean if another plug made that much difference, why wouldn't they recommend it or sell the motor with it? Or at least buy plug type "X" and put their name on it, in which case buying type "X" would be the same thing as a super plug?

I have a .61 and it runs great. However, the HS needle "clicker" (holds the needle steady) loosened up and was letting the needle turn during flight. I removed the HS needle, bent the "clicker" back so it would hold the needle steady and I have had no other trouble. Mine runs great about 1 3/4 to 2 turns out on HS. Low speed arm is set about 2/3 towards rear of plane. I am using Cool Power 15% and the Hangar 9 Super plug.

Great running engine. After you get it set, very little twisting required after that. Maybe just a click or two one way or the other depending on temp, humidity, etc.

Also, to prevent air leaks around the HS needle, I took a pair of forceps and stretched a 1/2" long piece of tygon over the needle and needle housing. Also, helps
reinforce the "clicker."

Good luck

An Evolution engine that is running too cold will have all of the symptoms described. A good way to test these engines is to watch how they run on the first crank of the day. See if you can get it to accept the throttle by advancing it gently. I've had to back off, advance, back off some, etc until the crankcase cleared. I got pretty good at it half of the time before W8YE gave me a hotter plug to try. If it is a plug problem, you may be surprised at how much more power you will get out of the engine, and the smooth throttle response.

I'm not sure now if the ones I've been around shipped with the H9 plug. I always pull them after some amount of break in time.

Jim,


Please read through my post #5.

Your current 'peace and quiet' may only be temporary.


You can go into the [link=http://www.morganfuel.com/omega_main.htm]Morgan's Omega page[/link].

The CP you are using will keep you model cleaner, but will not be advantageous for the wellbeing of your engine, which is its main purpose, I believe.

If you insist on all-synthetic lube, you better get some fuel from Europe, with Motul Micro, or with Sachs Aerosynth II/III/Aurosave, or go to Brian at [link=http://www.cooperfuels.com/]Cooper Fuels[/link] and get the wear protection Ester based oil will provide.

G'day Mate,
Just try one thing, a 2 blade 12x6 prop, don't change anything else, except for tuning, & see if it makes a diference.

Put a little castor in your Coolpower. Stay with a 2 cycle plug like a Tower, OS8, Fox RC long,KB-1L and avoid 4 stroke plugs . Take the stupid limiters off and make sure detent spring is firm against needle because I have seen the needles float around and they will drive you nuts. The OS springs are a good replacement.

In reply to all:

First, it's not my intention to argue or conflict any advise given here. I hate it when people do that to me.

I went to the LHS last night. Both LHS around carry the same thing. CP and Omega which are both made by the same company. There was another metal can of Glow Power or something, but it was full synthetic. I printed off the replies to this post and bought the closest thing I could find to the advice given at that time. I stuck with 10% for consistancy (I actually want to know what's causing the problem, not what masks it by turning up the nitro) and because there's no reason this motor can't run on 10% nitro.

I ended up with Omega 10% which is supposedly 10% nitro, 18% oil (20% castor and 80% synthetic by oil volume). It's the highest castor content I could find locally. If I can get the engine running properly, I'll do some more research and try to follow the advice given and get a higher castor content fuel. If nothing else, I have a jug of fresh new fuel to rule that out.

The LHS did not have A3 or Tower Power plugs. They DID have OS8 and type "F" and Hanger 9 "sport plugs" (whatever that is). I got OS #8 plugs so I'll work that into the tuning.

I pulled the glow plug that was in the engine. It looks to me like a Tower Power when compared to the pics I got off Tower's site. That's my unprofessional opinion. The only marking on the plug is an "H"

I bought a 12x6 Master Airscrew with my last Tower order. I plan to switch to APC props from now on, but that's what I have at the moment. Don't beat me up too bad. I'll try the 12x6 though. The manual calls for a 12x6. From what I read the 11x7 three blade I run is actually a little bigger than the 12x6's three blade equivelent anyways. I'd really like to stick with the three blade, but I'll try to tune out with the 12x6 because it was recommended here.

I pulled the carb last night. As luck would have it I DO have the supposed missing o-ring. Oh, well. So much for simple fixes.

BTW, thanks for posting the needle settings Safebet.

Lastly, I still have the clickers. I kept them to hold the needles still in flight BUT I adjust them around so they don't limit my ummmm, needle adjustment but they still hold the adjustment in flight.

I didn't get to run the motor last night. I was met at the door with honey-do's

The game plan:

-Use the fresh fuel I have
-Plug in an OS #8 plug, because because I have no idea what the current plug is and therefore can't buy one like it even if I do get it running properly with the original plug.
-I think I'll pull the limiters off and start with needle settings like Safebet. I'll reinstall the clickers later of push a piece of fuel line on the needles to hold it.
-I'm going to check the tank, lines, etc. etc. AGAIN.
-Tune it exactly like DarZeelon mentioned. Typically I point the nose up at about 30 degrees and tune, but I'll stand it on the tail this time.

Regardless of the outcome, I am going to try the 12x6 2-blade. Also will try an A3, Tower Power plug, and a fuel with high castor percentage as soon as I get my hands on them. Maybe a type F plug too.

If you're going to try plugs, the A3 is probably hotter than the F.

Spiral --First off the Omega is 17% total oil of which is 70% syn. and 30% castor. So your fine on castor content. The A3 is hotter than the #8 and colder than the #F . Tune for the #8 which can be had by any LHS in the nation.............If you were at 0% nitro the A3 would be an option....If you can't point plane straight up in the air for 30 seconds and not loose RPM , then your not ready to put plane up..........Millions of engines run OS#8 on 0-20% nitro .. I personally like the Fox RC long at $2.35 a copy with the same heat range as the OS #8 at about $7...............

Speedster- Are you sure the F is hotter than the A3?

30% castor. I guess I was misinformed. All the better then.

I'm gonna try to fire it up with the #8 and fresh fuel tonight. I gonna quit working 16hrs a day. Good grief. It's cutting into my airplane time! []

Correction I deadsticked the plane Spiral.

The 4 stroke plugs have to stay hotter because they don't fire on every stroke. OS's new plug chart is a little confusing. The A3 is touted as a economy #8 and a tad hotter............
http://www.osengines.com/accys/glowplugs.html
The chart is wacky The A3 is listed twice for air and surface . In the air it is positioned toward medium and car the hottest. If the average car user puts an A3 and their high nitro fuels it is rated as plugs per gallon. All older charts rate an F as HOT............
The # F is listed as the coldest airplane plug , but yet the # F is interchanged with MC14 listed as very hot and Fox Miracle as hot . Every manufacturer of 4 stroke plugs list them as med hot or hot but OS.........
http://www.scootworks.com/rdrc/gloplugs.html

I haven't tried the F in an Evolution engine, but I have used Saito SS 4 stroke plugs. I think the SS plugs are somewhere between the 8 and A3 from the way the engines react. I could be wrong, of course, but I would take the A3 over the SS. The whole idea is to get the Evo to burn off the fuel efficiently, which it does with hotter plugs. All of the Evos that I've been around stumble, sputter a bit, and have throttle up problems with OS 8s.

I'm not an expert on glow plugs, but it seems the F keeps heat longer for 4 stroke operation. There could be a difference between getting hotter and keeping the element glowing. That's what I'm thinking right now, but I could be wrong on this too.

Your link to scooterworks lists the F as being medium hot.

Listen BUDDY, I don't know who you think you are!!![&o]


Correction.. Drew4556 deadsticked it in...... And I must mention the most beautiful landings of the night, performed by "the Druid"

Yes we shall try the new fuel and clow plug and prop this Sunday and see what we get. Surely one of these options will work

I also have a .61 Evolution and have had the same 'surging' problem...I moved the fuel tank lower than the carb., which is sometine hard to tell how it's lined up and it 'vented' better and didn't surge...

jim

Yea, thanks. You're right, it is hard to tell about the fuel tank height in relation to the engine. The tank looks like 1/8" lower, maybe level with the engine. The only way I can change the height is a smaller tank or maybe reshape the floor of the tank so it sits lower. It's something to keep in mind though if I can't get it ironed out.

Funny you should mention the vent, no one else has until I was talking to a freind after the Sunday fly (ing attempt). I am going to check that the vent is off the roof of the tank. I'm pretty sure it is, but I'll check.

FYI.

We had a crew of three working on the engine.
First, the engine speed dropped when I pulled the glow ignitor off, so I changed the plug to a #8 (which I was going to do anyways). The drop went away.
We changed the 11x7 3-blade to a 12x6 2-blade. The 12x6 is exactly what is recommended by the manf.
Engine run like crap. Rough transition, rough everything, flaming out, tons of fuel blowing out, and hydraulic locked 20 times because the carb flooded..

I bent the stops out on the LS needle. We closed both needles, opened the HS up 2.5 turns and just cracked the LS..... I didn't think it would start bc the LS needle was open just 1/16 turn off of closed. Whad'ya know. She run pretty good. Transition was MUCH better, it actually had something that resembled a top speed, idle was the same.[sm=idea.gif]

I don't know what to say about the LS needle. It doesn't make sense. Anyways, there has been a huge improvement in the performance. I didn't get to flight test it because Murphy showed up and caused a bunch of problems...... The day wasn't a total loss, I was bummed bc I couldn't fly though.[sm=cry_smile.gif]

I am going to note all the advice and test each one guys. I'm still planning to use an A3 and an F plug to see if hotter will clean up the exhaust some.

All of the Evolutions I've been exposed to eventually had to have at least one of the needle valves adjusted beyond the stop setting.